REVIEW: X-15A-2 Special Edition for FSX and P3D

X-15A-2 Special Edition for FSX and P3D

A review by Ray Marshall

 

This folks is a very specialized, very unique and very exciting add on optimized for FSX, P3Dv2 and FSX-SE.  How often have you wondered what it would be like to fly at 300,000 feet or fly at Mach 4+, all by yourself?  Well, here is your chance to do it at will, whenever you like and in HD.

 

This may not be for everyone, but if this piques your interest you might like to know that several years of research and more than two years of development time was required. This is not your Grandmother’s rocket plane; this one is designed to take advantage of the newer, more powerful PCs and is compatible with all three of our flight sims. (FSX, FSX-SE, and P3Dv2)

 

This was the very early proving grounds for NASA’s manned space flights and the precursor of the Space Shuttle program.  Several of the X-15 pilots earned astronaut wings and two went on to become Project Apollo astronauts. The X-15 Research Program may have been the most successful aerospace program ever.  At least it is for sure the best documented.  I think just about every X-15 test pilot has written a book about his experiences and all make for some great reading.

 

The Xtreme Prototypes X-15A-2 Flight Manual is always up-to-date and you can access it from your PC, your tablet or iPad.  This comprehensive online manual has over 300 pages, 200 topics, 400 key words and includes very detailed systems descriptions, detailed ‘how to’, and checklists galore.  Of course, you will need a browser with an internet connection and a user account.

 

The high-resolution VC will almost reach out and touch you with the full 3D gauges and totally encompass you in the tight cockpit with over 60 unique sound effects.

 

Does it have detailed systems?

 

Oh yeah, in spades.  You can view the entire simulated systems list along with an extensive slide show at the product page (http://Xtremeprototypes.com/en/product_x15a-2_se.asp).  This is much more detailed than any complex aircraft that you may have in your virtual hangar.  In addition to all the expected aircraft systems many more highly specialized systems are required for flying at hypersonic speeds and way higher than the Concorde or even the XR-71A.

 

The X-15A-2A is both a hypersonic aircraft (Mach 5+) and a Rocket Powered Spacecraft (extreme altitudes well above the atmosphere) and each requires their own flight systems. Ailerons and rudders don’t do the trick in space so a Reaction Control System is required for maneuvering at altitude but the standard flight controls are needed for the glide home to a landing. 

 

Xtreme Prototypes’ goal was to create an add-on with the necessary features to make it as accurate as possible technically and historically, offering a higher level of realism, within the limitations and capabilities of the sim platforms. In addition of being visually impressive, this add on includes practically all the systems and functionalities found in the real rocket planes.

 

This new X-15A-2 Special Edition (version 2.0) is the first of Xtreme Prototypes next generation add on and contains eight variations of the X-15A-2 and three fictitious variations of the delta wing X-15AD-4 with solid rocket boosters, based on unfunded proposals.  We sim pilots actually have many more planes to fly than the real world X-15 pilots.

 

Next Gen HD Flight Models

 

The three highly detailed exterior models feature more than 1900 parts and 100 animations. The three fully functional 3D virtual cockpits contain over 1500 parts and 300 animated custom gauges and systems. A custom X-15 flight model was designed to reproduce the characteristics of rocket-powered high speed and high altitude flights in the simulator.

 

 

Xtreme Prototypes created a one million+ polygon mesh for this new 3D model in order to create as much detail as possible but went on to use very large mapping areas to achieve the high definition resolution throughout the different models. They were successful in finding that ‘right balance’ between quality and performance.

This is a chance for X-15 and rocket aircraft enthusiasts to go beyond books and films and jump in the cockpit of this extraordinary vehicle in a true simulation environment.

The Xtreme Prototypes X-15A-2 Special Edition will take you as close as you can get to flying the world's fastest aircraft!

Visit the X-15A-2 Special Edition product page (http://Xtremeprototypes.com/en/product_x15a-2_se.asp) for tons of information and step through a slide show of all the included models.

 

 

A Little History of the Real X-15 Rocket Plane

 

The X-15 Rocket Plane, sometimes considered the first spacecraft, wasn’t designed to take man’s first steps in space.  It was designed to gather data at a time when new technology was outpacing the engineers’ understanding of how aircraft behaved in high speed flight.

 

Chuck Yeager had successfully broken the sound barrier in 1947 in the Bell X-1, the most advanced aircraft at the time.  In 1953, Scott Crossfield cracked the Mach 2 threshold flying the Douglas built Navy Skyrocket.  Less than a month later, Yeager achieved Mach 2.44 in the X-1A.

 

 

Inconel X, a ferociously strong nickel alloy, gives the X15 its gunmetal black color. Inconel was chosen for the airplane's skin because it retained its strength up to 1,200 degrees Fahrenheit, a temperature the X15 would routinely experience at high speeds.

 

 

Not only was the X-15 the fastest, It may have been the best flight research program ever.
 

The X15 had a rolling tail. It not only had a pivoting surface that was movable in pitch; it also had differential movements so you could use it as an aileron [to roll the aircraft]. And that’s why it was called a "rolling tail." On the wing, the inset aileron you might think would be used for roll control were actually flaps that would dramatically increase the lift on final approach.

The X-15 is a vehicle built for actual flight testing.  In flight testing, you go out and you explore the unknowns. It is difficult to ascertain when the thinking leading to the X-15 began. It appears the effort started in the 1950-51 time period at Edward AFB when it was realized that without major advances in technology in all areas of aircraft design the ‘higher and faster’ theme was nearing a dead end.  The unprecedented problems of aerodynamic heating and high temperature structures appeared to be so formidable that they were viewed as 'barriers' to hypersonic flight.

 

But nearly everyone believed intuitively in the continuing rapid increase in flight speeds of aeronautical vehicles. The powerful new propulsion systems needed for aircraft flight beyond Mach 3 were identifiable in the large rocket engines being developed in the long-range missile programs. There was virtually unanimous support for hypersonic technology development, and it was generally believed that this would have to depend very heavily on flight research because there was no prospect of simulating the high temperature hypersonic environment in ground facilities.

 

In late 1952, R. J. "Bob" Woods of Bell Aircraft submitted a proposal that stated since attention is being directed toward very high-speed flight to altitudes at which atmospheric density is so low as to eliminate aerodynamic control, information was needed in that flight regime, and he believed NACA (National Advisory Committee on Aeronautics) was the logical organization to carry on basic studies in space flight control and stability.

 

This lead to a ratified  resolution that "the NACA increase its programs dealing with the problems of unmanned and manned flight in the upper atmosphere at altitudes between 12 and 50 mi and at Mach numbers between 4 and 10 and also devote a modest effort to problems of flight at higher speed and altitudes."

 

And thus the X-15 proposal was born at what appears as the most favorable of all possible times for its promotion and approval. Fortunately, there was no competition at that time from other glamorous and expensive aeronautical projects.

 

The X-15 Hypersonic Flight Research Program was officially started in 1954 and ran until 1968 when funding was cutoff mainly due to the NASA budget overruns with the Landing a Man on the Moon projects.
 

The original mission of the X 15 was to explore the phenomena associated with hypersonic flight.

                                                                                                                                               

 

The Shortest Overview of the X-15 Program ever.

 

Missions took place within the specially constructed High Test Range, an aerodynamic corridor that stretched approximately 500 miles (800 kilometers) by 50 miles wide (80 kilometers) from Utah across the Nevada and California deserts to Edwards Air Force Base. During a typical mission, the X-15 was carried to an altitude of 45,000 feet (14 kilometers) by a modified B-52 (of which two were built) and released.

 

The single pilot would ignite the single XLR-99 engine, which would burn for approximately ninety seconds, accelerating to a typical speed of Mach 5. After flying a parabolic trajectory above the atmosphere, the pilot would bring the craft in for a glide landing on the Rogers dry lake bed at Edwards.

 

The X-15 is also noted as being one of the few successful joint programs, bringing together the efforts of NACA (later NASA), the Air Force, and the Navy.

 

 

 

Highlights of the X-15 Research Program.

 

With absolutely no intentions of minimizing the considerable achievements, but simply for the sake of brevity so we can get to flying the simulated X-15A-2, the highlights are:

 

1955 - North American Aviation awarded contract to build three X-15 aircraft.

1956 – Reaction Motors awarded a contract to build the XLR-11 rocket engines.

1957 -  Construction started on first X-15

1959 – First powered flight by Scott Crossfield (with 4 smaller XLR-11 engines)

1960 – First government mission flight by NASA pilot Joe Walker

1961 -  Met design goal of Mach 6 and achieved altitudes in excess of 200,000 ft.

1963 -  Walker set attitude record of 354,000 feet (67 miles)

1967 -  Pete Knight set world speed record of 4,520 mph (Mach 6.7)

1968 -  Final flight of the X-15 program, the 199th on October 24, 1968

 

Technology Development and Achievements.

 

First use of a ‘man-rated, throttleable’ rocket engine.

First vehicle to employ a reaction control system for attitude control in space.

First development of advanced bioastronautics instrumentation, which includes biomedical.

First use of the all-improved full-pressure suit

First essential new technologies of thermal protection, guidance, and navigation.

 

All of these firsts and new technologies would later be used in the development of Mercury, Gemini, Apollo and shuttle space exploration programs.

 

 

With regard to human factors, the project demonstrated that a pilot could function at hypersonic velocities, high altitudes, and during periods of weightlessness. In particular, it showed that it was possible for a pilot to fly a reentry path, that is, to cross the region between relatively airless space and the thicker lower atmosphere.

 

Given the magnitude of its objectives, as well as the vehicle's sheer complexity, the total development time of five years from project approval to first powered flight (and two years from construction start) is quite impressive.

 

The estimated costs of the program appear similarly modest, particularly when compared to the space-related projects that followed. The program's total cost, including development and eight years of operations are usually estimated at $300 million (seven times the original estimate of $42 million) in 1969 dollars. Each flight is estimated to have cost $600,000.

 

The X-15's systems were spread across an exceedingly large number of contractors and sub-contractors. These included not only North American Aviation and Reaction Motors, but also General Electric (responsible for the Auxiliary Power Units), David Clark Co. (developer of the pressurization suit), the International Nickel Company (creator of the Inconel X nickel alloy for the fuselage), Bell Aircraft (ballistic control rockets), Sperry Gyroscope (developer of the in-flight electronic indicator systems), and many, many others. In all, more than 300 private firms participated in the project.

 

The X-15 flew to an altitude of 354,000 feet and reached a Mach number of 6.70. It flew its last flight almost 50 years ago, but to this day, except for the Space Shuttle no aircraft has flown half as high nor half as fast. The late Dr. Hugh L. Dryden termed it "the most successful research airplane in history."

 

 

The X-15 aircraft/rocket ship

 

The real X-15 was a single-place rocket-powered experimental aircraft built by North American Aviation in the late 1950's and early 1960's for NASA (NACA), the U.S. Air Force and the U.S. Navy to test flight at extremely high speeds and altitudes and to obtain data on the effects of such flight conditions on the aircraft and on the pilot.

 

The X-15 was capable of and achieved high speed and altitude records such as Mach 6.7 or 6629 fps (more than twice as fast as a speeding bullet) and 354,200 feet.

 

Three X-15 rocket planes were built during the X-15 research program, which overall cost more than $300 million (a colossal sum at the time). The program succeeded at demonstrating the ability of pilots to fly rocket-propelled aircraft out of the Earth's atmosphere and back to precision landing. Today, the X-15 can be considered as history's first reusable spacecraft.

 

After being dropped at a high altitude from a modified B-52 carrier airplane and propelled by its million-horsepower rocket engine at several times the speed of sound, the X-15 would fly to the edge of space, burn all its fuel, perform reentry into the atmosphere and finally glide its way back to land on a dry lake in the high desert of California.

 

The X-15-1, equipped with the "interim" Reaction Motors XLR-11 rocket engines, was rolled out in October 1958, and was transferred to Edwards Air Force Base for testing. Its first captive flight (while the X-15 is attached to the carrier airplane) occurred in March 1959 followed by its first glide flight in June of the same year. On January 23, 1960, the X-15-1, with NAA test pilot Scott Crossfield, successfully completing  its first powered flight attaining Mach 2.53 and 66,844 feet with the two XLR-11 rocket engines.

 

In February 1961, the X-15-1 was returned to North American Aviation for conversion to its design-mission configuration (which required the powerful XLR-99 engine), after completing 21 flights with the much smaller XLR-11 engines.

 

NASA pilot Bill Dana flew the X-15-1 for the last time on October 24, 1968. The No. 1 aircraft completed 81 flights during the entire X-15 program.

 

The X-15-2 aircraft arrived at Edwards in April 1959 and made its first powered flight with the XRL-99 engine more than a year later, in November 1960, after completing nine flights with the XLR-11 engines.

 

 

In November 1962, the X-15-2 airplane was extensively damaged during an emergency landing, after the flaps refused to operate and the left landing skid failed. It was decided to rebuild the airplane as a modified "advanced" version of the X-15, with a longer fuselage and external propellant tanks. The "extended performance" X-15A-2 was rolled out in February 1964.

 

In October 1967, Air Force pilot Pete Knight took the X-15A-2 to Mach 6.7 (4,520 mph), the fastest manned aircraft flight recorded to this day by a winged vehicle (excluding the Space Shuttle).

 

The X-15-3 was delivered to Edwards in June 1959, equipped with the XLR-99 engine. In August 1963, NASA pilot Joe Walker set an altitude record of 354,200 feet in the No. 3 aircraft. Sadly, the X-15-3 was lost in November 1967 after the airplane entered a hypersonic spin, descended in an inverted dive at almost Mach 4 and 65,000 feet and finally broke up, taking the life of Air Force pilot Michael Adams.

 

Together, the three aircraft completed 199 flights during a nine-year period, the 200th one being canceled several times in November and December, 1968. It was the end of the X-15 program.

 

After almost 40 years, the X-15 still holds impressive speed and altitude records. It was one of the most successful research aircraft tested at Edwards AFB.

 

Twelve test pilots flew the X-15: Michael Adams (USAF), Neil Armstrong (NASA), Scott Crossfield (NAA), Bill Dana (NASA), Joe Engle (USAF), Pete Knight (USAF), Jack McKay (NASA), Forrest Peterson (USN), Bob Rushworth (USAF), Milt Thompson (NASA), Joe Walker (NASA) and Bob White (USAF).

 

Today, the X-15-1 hangs from the ceiling in the main gallery of the Smithsonian National Air and Space Museum in Washington, D.C. The X-15A-2 is on display at the National Museum of the United States Air Force (Wright-Patterson Air Force Base, Dayton, Ohio).

 

A Typical X-15 Mission

 

 

 

In a typical X-15 mission the rocket airplane is attached under the right wing of a modified B-52 bomber and carried to an altitude of about 45,000 feet. Then, at a scheduled launch time, it is dropped and the pilot fires the airplane's mighty XLR-99 rocket engine to propel the X-15A-2 airplane at several times the speed of sound to high altitude and speed records.

 

If we exclude the climb to the launch altitude (during captive flight), a typical X-15A-2 mission would last for about 10 minutes, of which about 90 seconds (no external tanks) to 150 seconds (external tanks installed) saw the engine burning.

 

There seems to be no limit to the maximum altitude to be attained by the X-15A-2 in FSX or P3D. It is possible to recreate the highest flight of the X-15 program achieved by X-15-3 on August 22, 1963 of 354,200 feet. Unfortunately, speed is still limited to approximately Mach 4.65 on all current platforms.

 

After the airplane propellants are exhausted or the engine is shut down by the pilot, the X-15 performs reentry into the atmosphere and begins a shallow descent before her final glide to a dry lakebed in the high desert of California.

 

The military 360 degrees circle-to-land approach is used as the standard and will require the new desktop simulator test pilots to spend many hours perfecting the glide path, by varying the rate of descent with the proper bank angle and judicious use of flaps. landing skids, nose gear deployment and the slightest changes in angle of attack. Speed control is the key to a good landing. Remember, there are no go-arounds in the X-15 but the dry lake beds make for very long and forgiving runways.

 

The term used most often to describe the re-entry and glide to a landing of the X-15 is ‘Energy Management’.  This is simply the best and proper use of your speed and altitude to arrive at your destination at just the right altitude and the correct airspeed.  The glide angle is extremely steep and the glide speeds are way faster than most planes we typically fly in FSX or P3D.  The rate of descent (or climb for that matter) is astounding.  These guys use Feet per Second rather than feet/minute.

 

Can you imagine gliding at speeds twice as fast as the bullet fired from a high powered rifle? Hold on to your hat, the fun part is coming.

 

Getting started as a Simulator (desktop) Test Pilot for the X-15A-2

 

 

 

Xtreme Prototypes has made this as straight forward as possible. First, you need to purchase the new SE (Special Edition) add on and install it for your particular simulator. I have chosen to use the Lockheed Martin P3Dv2.5 for this review. I will also make a few flights in my FSX-SE (Steam Edition) just for a slight change of scenery.

 

One of the many advantages of having an online manual, other than it is always up to date, is the use of ‘jumps’ or internal links.  Simple click on the blue underlined words or phase and voila, you are there.

·         There are two ways to get started flying the X-15A-2 in the simulator:

 

 

·         The ‘detailed procedures’ checklist (the full set and the most interesting) and
The ‘condensed procedures’ or Quick Start method.

 

·         Plus, for all the ‘eager beavers’ the developer has included a magic Red Button on the panel to bypass all the normal and safe procedures to automatically start the engine fire sequence.

 

·         This is how the online Manual explains it. (Sorry, the links will not work for the non-owners)

 

·         The operation of the X-15A-2 add-on is very similar to the operation of the real aircraft. For proper operation, users must read the manual and follow the procedures carefully.

 

The X-15 is certainly no ordinary aircraft. As an experimental vehicle equipped with a powerful rocket engine that uses three different types of propellants, the X-15A-2 SE is very different from any conventional piston or jet aircraft that you may have in your virtual hangar.

 

Like a real X-15 test pilot, the desktop pilot needs some time to become familiar with the complex operation of this remarkable and unique aircraft and to become able to perform the required procedures described in the manual. It is simply impossible to jump in the cockpit of the X-15A-2 SE add on and expect to start the rocket engine and to take off without following the correct procedures, just like in the real aircraft.

 

All the necessary information to fly the X-15A-2 SE add on is in the online documentation. There are two sets of instructions: a detailed set, which contains the entire procedures involved in a real X-15A-2 flight (perfect for X-15 fans and more advanced desktop pilots), and a condensed set called "quick-start procedures", for those who want a shorter check list.

 

For beginners, a "magic" red button can be found on the main instrument panel to bypass normal procedures and start the engine ignition sequence automatically. However, following each step presented in the manual will make your overall X-15 experience much more realistic and enjoyable.

 

The X-15A-2 SE online manual contains a new section with complete system descriptions which was not included in the old (version 1.0) manual. All systems, switches, indicators, gauges, levers and handles are described in full.

 

If you're feeling overwhelmed by the cockpit of the X-15A-2, we suggest giving the manual a chance, as it was written with non-experienced pilots in mind. The aircraft is quite rewarding once mastered, but as most things in life, practice makes perfect!

 

 

For easier reading the balance of this review . . .
 

I am going to use XP for Xtreme Prototypes, the developer of this SE add-on and I am going to use X-15 for the X-15A-2 SE add on.

 

The Ground Rules for Flying the X-15 in the desktop simulators.

 

·         Do not expect to fly your X-15 from your desktop exactly like Scott Crossfield or Neil Armstrong may have flown it 50 years ago.

 

·         We will not be starting flights from hanging under the wing of a B-52.  No Mother Ship will be used at any time because there is not a B-52 in FSX or P3D.

 

·         Although, not realistic as related to the historical program, we will be taking off from a runway on a dry lake bed.

 

·         To simulate the B-52 launch, we will fly the X-15 using conventional airplane controls at reduced power but, at much higher speeds, to FL450 and establish a level speed of Mach 0.80 to start the daily flight profile from that point. This was where Scott and Neil dropped from the Mother Ship and ignited the rocket engine.

 

·         Remember, the X-15 is no ordinary airplane or spaceship.

 

Note:  The reason the real X-15 started flights from the B-52 at 45,000 feet were to save fuel by avoiding the initial climb in the dense air.

 

For purists, it is possible to simulate a high altitude launch from a carrier aircraft by using the slew mode commands to reposition the X-15 airplane without flying in real time. A 2nd option is to change the altitude and speed settings using  the map window, available from the "World" menu item on the simulator's top menu bar. You can also load one of the high altitude "launch" saved flights that come with the add on.

 

A special rocket propulsion simulation has been written specifically for the X-15 to approximate using a rocket engine with its related fuel systems and propellants in FSX and P3D.  Sorry, CTRL-E will not work for this one.

 

 

As a simulator test pilot you can make these flights simple or you can make them much more realistic, within the bounds of simulator reality.

 

By this, I mean you can start a launch from level flight at FL450 and 500 mph (m.78) by moving the throttle to 100% or you can use the 7 step engine restart procedure. These steps would simulate a true high altitude launch with limited fuel.

 

Unlimited fuel option switch – Off

Engine timer – Push knob for Reset

Engine precool switch – Precool

Engine Prime switch – Prime

Igniter idle switch – Igniter, wait 10 seconds

Ready to launch switch – On

Throttle – Start (click and move inboard to 50%

 

Chase Planes

 

During your mission, you can use the extra spot plane view to observe your flight because the X-15 has limited visibility out of the cockpit, especially at high pitch angles.  It also makes for some great screenshots. 

A typical real world X-15 flight would normally use 4 and sometimes 5 or 6 chase planes. These used call signs like Lead Chase, Chase 1, Chase 2, etc.  Usually two chase planes were assigned to monitor the B-52. Chase Rover was the 5th or 6th plane and was used to anticipate the likely problem areas for a given flight profile and be ready to give chase at that point.

 

 

The X-15 flew so fast that even the F-104 Starfighters could not keep up so the chase planes were staged along the profile route and would anticipate the arrival of the X-15 and give chase for a few minutes before handing off the task to another chase plane.  They were the extra set of trained eyeballs that kept a keen lookout for smoke or fire, or a wobbly piece of the metal.  They were also there to make sure two skids and the nose gear were down and locked on short final.

 

All the chase plane pilots were experienced X-15 pilots or soon to be X-15 pilots.

 

The chase planes used were primarily F-104N (N for NASA) models because the Starflighers could be made to imitate the X-15 lift-to-drag characteristics by setting the speed brakes, extending landing flaps, and selecting idle power.  Otherwise, they flew like a bat outta hell and could somewhat keep up with the speeding X-15 at least for a minute or two.

 

The F-100 Super Sabre and T-38 Talon were also used as chase planes.

 

 

Almost unlimited real data is available from the X-15 Research Program.

 

As an exception to the rule, simple internet searches will reveal almost unlimited amounts of interesting data from the 199 X-15 flights and many are documented so well that us simulator pilots can attempt to recreate those flights from our desktop.

 

This is of course, after you have read the 300 pages of the online flight manual and are thoroughly familiar with the capabilities and limitation of our add on and FSX or P3D.

 

Also as an exception to the rule, this add-on does not come with a few seemingly unrelated pages in a handful of pdf files.  This one come with the most comprehensive and best documented and easy to use flight manual that I have seen to date.  You will really appreciate the depth and understanding that the developer has of the X-15 and of FSX and P3D.  This is all about very high speed flight and severe angles of attack while expending limited amounts fuel or propellant and then the transfer of conventional airplane flight controls to the use of Reaction Control Units at the edge of space and then the very quiet and long ride home to a dry lake bed.

 

Assuming all goes well, your total logged flight time will be less than 15 minutes.  This will be Pilot in Command time because there is only the one seat in all models of the X-15.  It is just you, the black sky, that full panel of instruments and gauges and the ever decreasing amount of air moving over those stubby little wings.  But, the view is something to remember and talk about for a long time.  You don’t have to look for the curvature of the earth - when you push the nose over at your peak altitude, there it is, straight out the windshield.

X-15 Pilot Report – Flying the Mission and Returning

 

During one of my many internet searches I found a most interesting pilot report and I would like to share it with you here.  This is a real X-15 pilot, flying a real mission and returning.  As a real pilot myself, I found it fascinating and will use it as inspiration for a tutorial flight sometime in the future when I have a few hundred hours in the X-15.

We are going to start well into the story after the completion of the Preflight and Walk-around inspections because these are usually performed by a ground crew as is the cockpit check.  Just remember, this is no ordinary airplane.

 

Although your view of the world below is usually straight ahead, this late model X-15 has transparent electrical heating elements between the dual glass panels to keep the windows from icing over.  The cockpit is unpressurized below FL350, but it is air conditioned.  Above 35,000 feet it’s pressurized to 3.5 psi using nitrogen.  Your pressure suit gets another nitrogen feed to keep it at 3.6 psi.

We aren’t even going to discuss the ejection seat in this review because it is almost an airplane itself.  If you need it, it will unfold fins, put you in a nice attitude, escort you to a lower altitude, then blow pieces of itself away and deploy your chute.  According to the manual, it will ‘permit safe pilot ejection up to Mach 4.0 in any attitude and at any altitude up to 120,000 feet”.  You can trust any or all of that statement and limits, just keep in mind that such an ejection has never been done.  Ever.  This powered chute sounds a little more complex than the Cirrus SR-22.

 

Moving along, once you are settled in your seat, you’re looking at about 130 odd gauges, switches, lights, and controls of assorted descriptions.  First, you will notice a conventional center stick and rudder pedals.  There is also a console stick at your right hand for use when G loads make it difficult to use the center stick.  These are coupled together with a system of bell cranks that sum their inputs with those from the Stability Augmentation System (SAS).  The horizontal stabilizer position indicator is located on the cockpit wall next to the console stick.  This is a must check item before dropping from the B-52 and again before beginning reentry.

 

The third stick, for the ballistic control system, is at your left hand.  When the ballistic control rockets are armed, you can:

 

Move it left or right to control yaw

 

Rotate it to control roll by firing wing thrusters

 

Move it up or down to control pitch

 

Other ballistic inputs come from the Reaction Augmentation System (RAS, which is the no-air equivalent to the SAS.

 

The same left-side panel houses the speed brake lever and the throttle. The throttle allows a choice of "off" or any thrust setting between 50% and 100%. In the early days it could go down to 30%, but the XLR-99 rocket motor was prone to flickering out when it was developing only a measly 4 1/2 tons of thrust.

 

The main instrument panel is divided into three sections: Engine instruments on the lower left, APU's on the lower right, and flight instruments at top center. Both engine and APU sections are mainly an assortment of pressure gauges, temperature gauges, fire warning lights, and sundry switches.

 

The most prominent flight instrument is a big attitude indicator, planted squarely in the middle. It looks fairly ordinary, but it's accurate throughout 360 degrees of rotation around any axis you care to name.

Scanning clockwise around the attitude indicator, starting just below it, the flight instruments are...

 

·         Roll rate indicator, calibrated to 200 degrees per second. The X-15 is pretty agile in roll, but you need to limit the rate to no more than 50 degrees per second in some conditions for the sake of stability.

·         Altimeter: Looks ordinary, but it has a cutout that unveils warning strips when you're dangerously low -- under 16,000 feet.

·         Airspeed: Usable from 100 to 1,000 knots; has a Vernier drum to show speed to 1 knot anywhere in this range.

·         Angle of Attack: Reads -10 to +40 degrees. Stay below +20 degrees to avoid stability problems, or +17 1/2 after jettisoning the ventral.

·         Accelerometer: Reads +12 to -5 G's. Allowed load factor ranges from +3/-2 G with a full load of propellant to +7/-3 G at burnout weight.

·         Azimuth indicator: A high class compass. Like the attitude indicator and the next few instruments, its reference is the gyro-stabilized platform in the "Inertial All-Attitude Flight Data System".

·         Inertial height (altimeter): Shows altitudes up to 1 million feet. The little hand reads hundreds of thousands, the big hand reads tens of thousands.

·         Inertial speed: Calibrated for any speed up to 7,000 feet per second. That translates to 4,150 knots or 4,773 mph.

·         Inertial vertical velocity: Reads up to 1,000 feet per second (60,000 fpm) in increments of 100 fps.

·         We'll skip the remaining cockpit clutter, only because it's generally less amusing, though some of it will appear in the test flight.

·         Pics Cockpit, left side, right side, Instrument panel.

 

OK, time to head out to Launch

 

You, the pilot, arrive at the Base while others are finishing final fueling and system checks in the hours approaching dawn. You'll start with the X-15 already hanging from a pylon on the B-52 carrier aircraft.

 

Don't bother with a nitty gritty total hardware preflight; the taxpayers thoughtfully provided a whole staff to do it for you. Anyway, you're cooped up in a pressure suit, pre-breathing 100% oxygen.

 

After entering the cockpit, strap in and run through the interior check. That's 120 checklist items, ending with "close canopy". By now the B-52 is supplying power, breathing oxygen, nitrogen, and liquid oxygen to top off loss from the oxidizer tank.

 

That LOX loss is due in part to precooling the engine, which you initiate in the captive takeoff checklist. While precooling, LOX flows through almost allof its usual path to the engine, then dumps overboard at the liquid oxygen prime valve. You'll precool for 10 minutes, then start a schedule of 20 minutes off and 7 1/2 minutes on.

 

Takeoff isn't just you and the B-52.  Typical missions will add three chase planes, rescue helicopters, a C-130, and an array of ground vehicles deploying to places between your planned takeoff location and Edwards.  Some of them go to the dry lakes that might be needed for emergency landings along the planned route of your flight.

 

A few things will need heat during the climb, so be sure to turn on the heaters for the windshield, your face mask, and the nose ballistic rockets (the X-15's nose, not yours). Also ask the B-52 crew about the hook heater.

 

Once at altitude, go through the 27-item prelaunch checklist. Among other things, you'll switch to the X-15's breathing oxygen, shut off liquid nitrogen but not gaseous nitrogen from the B-52, and start the APU's.

 

Next comes the 29-item pre-countdown checklist. Among other things, you will:

 

·         Stop LOX transfer from the B-52.

 

·         Cycle the propellants tanks from vent to jettison, then to pressurize.

 

·         Check the flight controls and trim settings. Launch control surface deflections should be 0 degrees for everything except the horizontal stabilizers, which should be 0 to 2 degrees leading edge down. Be careful - if the position's too far off when you drop, the X-15 can pivot on its pylon and slide into the engines just outboard on the B-52.

 

·         Turn on instrumentation.

 

·         Start the final engine precool cycle.

 

·         Set the engine prime switch to PRIME. This opens the liquid oxygen and ammonia main feed valves and the hydrogen peroxide upstream safety valve for the turbo pump, and it feeds helium to the engine control and purge systems. It takes 30 seconds to complete priming.

 

·         Depress the turbo pump idle button. This opens its H2O2 downstream safety valve, allowing the pump to begin running. When it's brought ammonia pressure up to 210 psi, the turbo pump speed control system will take over to keep it at idle speed.

 

·         Set the igniter idle switch to IGNITER. Now you have 30 seconds to finish preparations, drop, and fire the XLR-99's main chamber or to shut down. Don't leave the igniter on longer, or the XLR-99 will be damaged by overheating.

 

What happens when you go to igniter idle is this rapid-fire sequence:  

 

 

The engine is purged with helium for 2 seconds.

 

Three spark plugs are energized in the first stage igniter, which is a small combustion chamber ahead of the 2nd stage igniter and main chamber.

 

Ammonia and gaseous oxygen enter the 1st stage igniter and start burning. The gaseous oxygen is produced by routing liquid oxygen through a heat exchanger that surrounds the turbo pump exhaust.

When chamber pressure rises sufficiently, gaseous nitrogen from the B-52 flows in to mix with the 1st stage igniter gases.

 

Ammonia and LOX begin flowing to the second stage igniter, which is a larger chamber, where they're ignited by the jet of burning gas from the 1st stage. This igniter alone produces 1,500 pounds of thrust.

When the 2nd stage igniter and main chamber build to 150 psi, about 5 seconds later, the jet into the main chamber is sufficient to light it up. You're ready to go, so ask for the countdown -- fast!

 

They're serious about that 30 second time limit for either lighting up or shutting down. When there's 7 seconds more of idle time allowed, an IDLE END caution light comes on. When time runs out, a NO DROP light tells you to shut it down.

 

So... when you get through the brief countdown and you drop, don't waste much time before moving the throttle from OFF to at least 50%. That'll light the main chamber, giving you the second part of a big one-two punch.

 

Part 1 was the drop itself. Starting to fall may sound like a gentle and mellow start, but it can feel more like being catapulted straight down. In the early flights even a short countdown wasn't adequate preparation when the B-52 crew initiated the drop -- NASA soon changed the system so that it would be the X-15 pilot who tripped the release, giving you at least a feeling of being just a bit more ready for the even.

 

Actually Flying the Mission and Returning

 

After you light the torch you need to fly precisely in the face of some unusual challenges. Let's say the mission at hand is a more or less a full bore altitude flight.

 

Part 1 is to go to full throttle and pull up to just the right climb attitude. With 57,000 pounds of thrust from the rocket, maybe even 60,000 on a good day, you start at 2 G's acceleration while your tanks are full and your gross weight is about 33,000 pounds. As you burn fuel and oxidizer, with weight dropping to barely over 15,000 pounds, acceleration doubles to 4 G's. Rocket motor performance can vary depending on lots of factors that sound small, but sometimes they add up instead of cancelling each. If you compound that deviation by missing your planned climb attitude by as little as 1 degree, the results begin to look astronomical. Flying with precision that would give most pilots enormous pride, your imprecision can easily produce a 30,000 foot overshoot or undershoot in maximum altitude.

 

All that precise flying happens on the gauges. Let's say today's mission profile puts you in a climb attitude of 42 degrees. If you glance out the windows in this attitude you see nothing but dark blue sky that's quickly getting blacker as you climb. With no visual cues and thrust overpowering gravity your sense of balance lies - it feels as if when you pulled up the rotation never stopped and you've gone past vertical, to an inverted attitude! Those instruments connected to the gyro-stabilized inertial platform are what you need to believe to stay in touch with reality.

 

As you climb out of the atmosphere the aerodynamic flight controls lose their effectiveness. Here you have to transition from flying with the right hand side stick (and rudder pedals) to flying with the left-hand side stick, for the hydrogen peroxide thrusters. That's unless you have the luxury of flying the #3 X-15- its adaptive controller, the MH-96, lets you use only a single side stick and automatically blends aerodynamic controls and reaction controls.

 

On today's altitude flight either you cut the engine after an 82 second burn or the X-15 burns enough ammonia and LOX to burn out by then without your help. That's another variable that makes a big difference in peak altitude, if you have power on for an extra second you can expect a sizeable overshoot. Now you're weightless, still climbing in a ballistic arc. In a couple minutes today's flight tops out at about 300,000 feet over the high deserts of Nevada and southern California.

 

As you pitch over you can now catch a spectacular view of the southwest U.S. The view shown here is the Colorado River Valley from 210,000 feet. In the words of Robert White, "My flights to 217,000 feet and 314,750 feet were very dramatic in revealing the earth's curvature ... at my highest altitude I could turn my head through a 180º arc and wow! - the earth is really round. At my peak altitude I was roughly over the Arizona/California border in the area of Las Vegas, and this was how I described it:  looking to my left I felt I could spit into the Gulf of California.  Looking to my right I felt I could toss a dime into San Francisco Bay." If the coast is clear that far north, you can just about make out he Puget Sound, nearly a thousand miles away.  I wonder if any missile boats are docked there today.

 

Coming back down you carefully establish the correct attitude for reentry into the atmosphere as a very fast glider with truly crummy glide performance. REAL gliders are painted white to help them keep cool, by reflecting solar energy. The X-15 is black to help it keep cool, by radiating the heat that builds up rapidly from air friction. A few parts of the nose, wings, and stabilizers briefly hit temperatures up to 1,200 degrees and glow red hot during reentry.

 

Pulling out of the reentry is one of the maneuvers that lets the pilot know this is no ordinary realm of flight.  If this altitude flight topped out at 350,000 feet you can expect to be coming out of reentry at Mach 5.4 in a 40-degree nose-down attitude.  Pulling out of this dive requires pulling an average of 5 g's for about 20 seconds.  If you only need to turn through a mere 10-degree heading change at Mach 5.3, expect to pull 3 g's for 20 seconds.

 

There are a few unusual but modest control couplings. At low angles of attack, roll inputs couple to a favorable yaw.. Above Mach 2.6, roll response gets quicker as angle of attack increases.  At least that's what the manual says - Scott Crossfield reports that there's virtually no roll/yaw coupling, she rolls nicely.

 

As the X-15 slows down and drops, stability degrades and allowed yaw angles decrease. Below about 40,000 feet and Mach 0.5, minimum control speed is determined by stability; above that point it's governed by buffeting at the tail. Stability margins allow you to fly AOA's up to 20 degrees, but the pre-stall buffet starts at 13 degrees.

 

 

Stability problems can be evil. Conventional wisdom says that you will need the electronic stability augmentation systems (or the built-in SAS functions) or your chances for a survivable reentry are puny. Hypersonic stability trouble can bite in big ways, including the sort of inertia coupling that earlier killed Mel Apt in the X-2.

 

 

Going back to being a glider approaching the landing pattern, expect a sink rate of about 150 feet per second (9,000 fpm) at Mach 0.75. That gives a max L/D of almost 5:1 at 40,000 feet, but realistically you can expect closer to 4:1.

 

 

Finally, you have to land at Edwards Air Force Base. Field elevation is 2,200 feet for a somewhat groomed runway on the dry lake bed. Approach will be sort of a 360 overhead pattern; it'll actually be a tightening spiral because true airspeed drops while you descend at a constant indicated airspeed.

 

Landmarks in the pattern on this flight are:

 

145 seconds to touchdown, 28,900 feet: High key point

 

This is 2 miles short of the approach end of the runway and 1.5 miles to its right. You should hit it at 300 knots and roll into a 45-degree banked turn to the left. You'll maintain 300 knots IAS and the 45-degree bank until just before you flare.

 

108 seconds to touchdown, 20,900 feet:

 

270-degree key point: "Crosswind leg",

 

90-100 seconds to touchdown, below 17,000 feet:

 

Pressurize the propellant tanks. They were switched to Vent at burnout, but they need pressure now for two reasons:

 

To prevent sand and dust found at low altitudes from entering the tanks through their vents.

 

To keep the tanks from collapsing. The vents may not keep up with the rapid change in ambient pressure at low altitude.

 

75 seconds to touchdown, 14,100 feet:

 

Low key point, "downwind abeam" (opposite approach end of runway, about 3 3/4 miles from it).

 

46 seconds to touchdown, 8,500 feet:

 

90-degree key point, "base leg".

 

30 seconds to touchdown, 5,500 feet:

 

Jettison the ventral.

 

19 seconds to touchdown, 3,500 feet:

 

Roll out onto the runway heading and drop the flaps. You're still at 300 knots.

 

15 seconds to touchdown, 3,000 feet:

 

Drop the gear and begin to flare. The flare is a 1.5 G pullout.

 

 

 

8 seconds to touchdown, on the deck, just above 2,200 ft field elevation:

 

End of flare; airspeed's dropping through 262 knots.

 

0 seconds:

 

Set it down when airspeed drops to 200 knots and ride until you stop. With no brakes and no steering, you're a passenger now.

 

Well, not entirely. You can actually steer a little bit by using the stick as if you're banking: The stabilators will shift weight from one landing skid to the other and will steer you in the direction you've moved the stick while you're fast enough.  When the speed drops off, force generated by the stabilators drop too, and you do finish the rollout as a non-steering passenger.

 

Finally, go through the after-landing checklists to secure everything.  As the B-52 offers its salute with a flyby, convince the folks on the ground and the ones who get out of the chase planes that a modest celebration is in order.  Or maybe a big celebration, this flight may well have been another milestone in aviation history.

 

Can flight simulator pilots fly with precision like these?

 

For one, I know for sure that I can’t fly to a one second burn time or a one degree attitude deviation, but then again we are flight simulator pilots and we can practice and practice and practice. 

After reading some of the available memoirs and other tall tales from the actual X-15 pilots, they were not nearly as precise and reliable as one might expect.  An overshoot of 10,000 feet of altitude was very common as was forgetting to perform a prime maneuver as part of a mission or forgetting something as basic as deploying flaps for landing gear was almost commonplace in the test program.

 

Saved Flights

 

The X-15A-2 SE add-on includes six saved flights (two for each X-15A-2 SE model) that can be used as “templates” for starting a new X-15 flight in the simulator. A seventh saved flight is included for the purpose of inspecting the aircraft on the ground.

 

Loading a saved flight has the advantage of presetting all X-15A-2 internal systems to OFF and preventing the rocket plane from moving by itself on the runway at the beginning of a flight because the engine was running in the previous flight with the parking brake not applied.

 

It is also easier to prepare the X-15A-2 for takeoff or to simulate a high altitude launch by loading one of the saved flights.

Some Observations – Why the simulated edition may be better than the real thing.

 

Although I consider this X-15 simulation the most unique, sophisticated, and thoroughly enjoyable add on that I own.  I do wish to make it perfectly clear that you can only approximate any of the historical missions, due to the absence of the B-52 carrier ship.

 

Because XP went to great lengths to ensure the missions and flights are truly enjoyable when flying in the simulator, I think the simulated missions are probably more rewarding than the real ones based on what I glean from the historical flight records and the many books and articles that I have read.

 

This is because we do not have to fly to those test pilot specs of one degree pitch or main engine burns timed to the nanosecond.  It is no big deal should we shut down the rocket engine a few seconds early or if we overshoot our target altitude by ten or twelve thousand feet by not shutting it down on time.

 

I think it is just as enjoyable trying to glide from near space to a runway in the middle of a dry lakebed 100 miles away without overshooting by 10 miles or under shooting by a similar distance.  I guess I still prefer a glider to bailing out.

 

The advantages we have as desktop simulator pilots as compared to the real world test pilots of 50 years ago are plentiful.  For instance, we have much better visibility from the cockpit and we have the option of having that huge engine timer directly in front of our nose when we need it or be able to remove it for better visibility when landing.  Our gauges and instruments are probably more reliable and are certainly easier to read.

 

We also can takeoff and start a mission on our own internal power without depending on a mother ship or carrier.  Another big advantage is that we do not have to wear the pressure suit for the entire flight and we can choose to deviate from the mission profile at any time for any reason with no adverse ramifications.

 

We can choose to become a chase plane pilot at any time for any length of time and observe the X-15 from any angle we choose and then instantly return to the X-15 pilot seat as the mission pilot.

We can save a flight at any time or location at our discretion or open one of the XP provided saved flights to start or continue a mission.

 

And the best one of all is that we can simply press the pause key if we are about to die, just get bored, or the wife calls out that dinner will be ready in 5 minutes.  We can also drink coffee while we set all these new records.

 

The Pressure Suit

 

 

Each pressure suit was custom made for each pilot and required several trips to the David Clark office in Worcester, MA  for fit checks and tests.  This was important because back then you could not open your helmet or facemask should your oxygen supply fail or you needed to scratch your nose or wipe the sweat from your eyes while waiting sometime for hours while suited up and ready to fly.

You also needed to be able to reach each and every switch, knob or control in the cockpit in both pressurized and unpressurized conditions.

 

It is hard to believe how restrictive pressure suits can be but they are absolutely necessary to stay alive in the harsh environment of high altitude flight.

 

My Personal Pressure Suit

 

 

I can appreciate these necessary restrictions because I was a member of the fueling team for the Lunar Module for all flights up through Apollo 14. This placed two or three Grumman Aerospace employees, me being one of them, inside the SLA (shroud) and in amongst the folded landing gear and protective layers of foil of the Lunar Module for most of a day, sometimes two in about 45 minute stretches. 

 

We were fully encased in the most modern ground-based space suits that NASA could buy at the time.  We wore SCAPE suits, Self-Contained Atmospheric and Pressure Ensemble, maintained by the Bendix Corporation and used for ultra-hazardous duty at the Kennedy Space Center in the late 60s.  The air was generated by light weight (yeah right) ‘liquid oxygen generators’ carried on our backs and connected to a distribution unit mounted on our chest for metering the air inside the protective suit. This was both breathing air and cooling air.

 

This was quite an ordeal and much more stressful and tiring than one would think.  The old guys really had a tough time with it.  I was young with a flat belly, in perfect health and stayed in shape surfing and chasing girls.  The beer drinking bosses and others that were overweight and out of shape really struggled.

 

It took ten times longer to suit up, transport to the launch pad, ride the elevator 300 feet up the Launch Tower and then squeeze into position under the LM engines to connect the high pressure lines and turn the valves or to monitor the weight gauges that measured the LOX, UDMH and Oxidizer we were using to fuel the lander.

 

This is probably the most poisonous stuff man has ever created in addition to being highly volatile.  No one has ever inhaled one breath of this stuff and lived to tell about it.  So, it was very important not to snag your SCAPE suit or have a bad seal on your gloves, boots or helmet.

 

 

Invariably, as soon as I gave the two thumbs up to the suiting crew my nose would start itching or a bead of salty sweat would drip into my eyes or my headset would quit working and provided we had enough time they would crack the seals and scratch my nose for me or wipe my brow.  Remote headsets were not very reliable back then, but one of the three must be working or the fueling could not continue.

A side note: the emergency egress that was planned was fortunately never put to the full, life saving test.  The lightweight but space travel worthy SLA walls were rather thin so some brave sole designed a ‘cookie cutter’ emergency escape hatch connected to a couple of two fully-charged 72 cubic foot SCUBA tanks and a big red button that would blow an instant hole in the protective walls and swing out of the way for us to grab a waiting T-handle pulley arrangement connected to a wire cable that would allow the three fuelers to individually ride down from 300 feet in the air to a waiting bunker below ground.

This escape was powered by Sir Isaac Newton’s gravity and the cable tweaked and stretched for our general weight and height.  We supposedly would crash through a self-sealing door at the end of the tunnel and make a soft landing on a pile of memory foam (yup, invented by NASA for us).  We had enough food and water for about 3 days in the underground recovery room. 

 

 

We looked forward to testing and calibrating the system. This took several days, maybe a week, and required that we be suited up and standing on a temporary platform 300 feet up.  We grabbed the T handle and took a ride that Disney would make a killing on. This may have been the original ZIP line! We usually started with a ballast dummy named Oscar and let him drag the ground and break his legs first, or end up dangling 30 or 40 feet above the ground while the Saturn V exploded, as the engineers tightened or loosened the cable.  Sometimes Oscar just crashed into the door at full speed that failed to open and was instantly reduced to a pulp.  BTW, we didn’t get paid any extra for this work, other than a ton of overtime pay.

 

This rig had to be removed, then moved and placed at a slightly higher position and adjusted for height and distance for North American fuelers for the Apollo Service Module emergency escape when it was their turn in the barrel.

 

The first one out the hatch might have had a 1 in 100 chance of living to write a book, but the number two and three guys didn’t have a chance in hell of making it out if the complex exploded.

There was a neat little placard near the big red button, that said something along the lines of . . .  This is a life-saving emergency egress system but be aware that pushing this button will set the landing of a man on the moon schedule back a year or more.

 

No two Flights or missions are ever the same.

 

This is just the nature of the aircraft/spacecraft and the flight profiles.  Just try repeating a glide from 300,000 feet to a single runway 100 miles away or to repeat a 35 degree nose up climb at Mach 4 with a climb rate of 60,000 fpm while targeting a peak altitude for zero burn nose over at any given near space altitude. The chances of doing the same exact thing twice for a full 10 minutes mission are between zero and zero.zero.

 

Interestingly, I have just returned from a holiday on the Mexican Rivera and I took one of my X-15 books along.  I got about half-way through Milton Thompson’s at the edge of Space – the X-15 flight program.  This is just one of many very detailed books available describing the almost unbelievable events in the life of an X-15 test pilot.  Milt Thompson was already an experienced test pilot when he was accepted into the X-15 program, but he stated that he flew his first X-15 mission at least 500 times in the simulator and many times in the specially equipped F-104 to simulate the approach to landing phase in the 3 months prior to his first X-15 mission.

 

 

I gather that Neil Armstrong, one of the first X-15 NACA test pilots, is lucky to have lived through many of the crazy stunts and pilot mishaps to be able to eventually fly the Lunar Module to the first manned landing on the moon.  The support flights and day to day flying skills of this bunch of specialized test pilots makes for some hair-raising experiences and would never be tolerated in modern times.

 

Buying Books

 

I typically buy 2 or 3 books as part of my research for writing these Avsim reviews and this one was a true gem.  At a total cost of $4.00 ($.01 + 3.99 shipping) I was able to buy a signed, near mint condition, hardcover edition of Milt Thompson’s book on his X-15 experiences using the Amazon.com used book feature and as a bonus had it delivered in 5 days.

 

 

Milt Thompson, X-15 pilot number 9, completed 14 flights and was the Technical Advisor for the 1961 movie, X-15.  He says the movie sucks but the flying footage is authentic and worth watching.

The X-15 Rocket Plane book by Michelle Evans (2013) is highly recommended reading by the Xtreme Prototypes crew.  Today’s used price at Amazon is $8.99 + s/h and it is filled with some great stories and many color photos and illustrations. This has to be the most comprehensive book ever on the X-15 program with 70 interviews and 2,100 photos. This one tells the entire story, not just the pilots point of view. While waiting for delivery, you can check it out online for free at http://mach25media.com/x15index.html

 

The Online Flight Manual

 

The more time I spend reading and referring to the manual the more I appreciate how well done and how complete it is.  Just the time saved by using the jumps or links and being able to return back to where you jumped from is outstanding in itself. But, it is so much more than a Flight Guide or Flight Manual.  There are high quality screen shots or images for most every subject, panel or compartment.

 

 

I especially like the fact that I can use my iPad, my iPhone, or any PC in the house to access the website and the online manual.  Using the online links is far superior and much easier than using iBooks or any of the pdf readers.

 

The BIG Poster

 

A good search string will reward you with a nice oversized, crystal clear pdf file of the NASA/North American Aviation X-15 poster.  It will take most of an evening to read the entire poster but, it is well worth your time.  Just about the entire program history and technical achievements, along with the pilot’s bios, a cutaway view, the ejection seat, a flight profile, the records, the triumphs and tragedy, the key to the panel instruments and gauges, the B-52 Carrier, and more can be found by zooming small sections to whatever reading level is comfortable.

The pdf file of the poster is of excellent quality and can be zoomed to easily read the smallest print.

 

One of the better links for the poster and to read more about the X-15 program and experience the many videos is
http://crgis.ndc.nasa.gov/historic/X-15.  Be sure to read about the single fatality and the only hypersonic spin in the history of human flight. For a great interactive experience go here. http://www.nasa.gov/eXternalflash/x15_interactive/

 

Checkout the illustration that I made, it shows the zoom quality of this X-15 poster.

 

 

The actual poster is about 3X my full screen 24 inch wide screen monitor.

 

 

For the plastic model builders – this one has lots of choices, some even reasonably priced

A google or bing search for ‘plastic airplane model kit X15’ will return an eye-full of boxed models, some available at Amazon.com, or your favorite online model shop and there is always a dozen or more available for your bid at ebay.

 

 

Getting Ready to Fly the X-15 in your simulator

Make sure you install the correct version of the X-15 in the correct simulator.  A few words of caution.  The FSX users must have the Acceleration Pack installed. FSX Gold will work but not SP2 only.  No support for FS2004.

 

The P3Dv2 is native and cannot be used with FSX.  Windows XP and Vista are not supported.

 

It seems there is not any upper altitude limit in FSX/P3D but there is a speed limit of Mach 4.65 in all platforms.  I bet those Microsoft Aces never dreamed FSX would actually have a high quality add on flying at these speeds and altitudes.

 

Some very recent news is that the advanced version of the X-15 for X-Plane has been delayed.  This one promises to be even more fun with the upper speed limit being raised and the ability to launch from a B-52.  Check with the XP website for the most up-to-date news on the Laminar Research X-Plane edition.

 

Performance using your simulator

 

As one should expect, the X-15 was designed as a test aircraft to be flown in a special area – the barren areas of the Nevada desert and the Edwards AFB area of California.  It was not designed to fly in high traffic areas, over high density terrain or major cities.  This could considerably affect you frame rate and have a negative impact on performance.  Test Aircraft are usually only flown in good weather so the chase planes can see and assist and the pilot would not have additional external factors to consider.  During test flights the whole area is restricted to any civilian flights and only the test vehicle and the chase planes will be in the air.

 

So not only are  the realism sliders all set full left, most of the graphics, scenery, weather, and traffic sliders should also all be leaning to the left.

Because this complex add on is graphically intensive you will also want to make sure your video driver in up to date and that your antivirus program is either off or not actively scanning while you are flying the X-15.

 

Recommended Settings – This is extremely important

 

Actually the recommended setting could be considered required settings.  These are very different than any other complex add on that I have on my system.  You will find illustrated settings panels for each simulator version.  Some settings are required that we normally do not use, such as auto-mixture and the unlimited fuel option due to the custom fuel management system designed for the X-15 that bypasses the simulator’s fuel management system.  Do pay attention to the Realism settings.  These are all full left whereas mine are usually all full right for the type of flying that I do.

 

This is the first add on that I have for P3Dv2 that includes screenshots of the individual slider settings and recommendations.  Even Orbx has failed to provide this level of assistance for their airport add ons and scenery packages for P3Dv2.

 

 

Don’t expect to feel the g forces

 

Xtreme Prototypes has done a wonderful job with the visuals, sounds, animations, and various models to choose to fly in the simulators but, they can do nothing to approximate the g forces generated at main engine start and ignition or the 6, 7, 8 g turns and pullouts where your eye balls are either being pulled outward or downward and your butt feels like lead.

 

The flight testing area

 

I suppose you could slew or use the Map feature to place your X-15 at just about any altitude or location and fly until you exhausted the fuel and then glide into a major metropolitan airport.  This is not what is intended at all.

 

 

The Edwards AFB and the additional dry lake beds covering most of Nevada and the California Mojave desert, including Area 51 is the intended area for flying the X-15.  This is just about the most desolate area I can imagine.  I visited the Mojave area and toured Burt Rutan’s Scaled Composites operation a few times and it is truly rough country.

 

The 4,000 foot diameter compass rose on Rogers’ dry Lake bed is a site to behold. I can’t even imagine how much tar it takes to layout the runways from time to time.  These lines are typically 8 feet wide, about 3 inches deep and miles and miles long.

 

You can find several large scale maps and diagrams to use for your simulator flights at Michelle Evan’s X-15 web site. Use this link http://mach25media.com/Resources/X15TourMaps.pdf  You will need to have several ‘alternate’ landing sites and know the general direction of the available ‘runways’ and the length of the lake bed just in case you misjudge your glide path, angle or speed.

 

Saved Flights

 

The X-15A-2 SE includes six saved flights (two for each X-15A-2 SE model) that can be used as “templates” for starting a new X-15 flight in the simulator. A seventh saved flight is included for ground inspections and aircraft walk-arounds on the ground.

 

Loading and starting from a saved flight has the advantage of presetting all X-15A-2 internal systems to OFF and preventing the rocket plane from moving by itself on the runway at the beginning of a flight because the engine was running from a previous flight with the parking brake not applied.

 

I think it is much easier to prepare the X-15A-2 for takeoff or to simulate a high altitude launch by loading one of the saved flights.  The high altitude saved flight will start you out as if the B-52 has just dropped you off the pylon at Fl450 and doing 500 mph.  You have to hold your heading and immediately start the rocket engine start sequence.

 

After the flight is loaded in the simulator, you can continue with the normal or quick-start procedures, or click the automatic ignition sequence start button on the main instrument panel to start the engine.  Remember, this is not an instant start, you will have to watch and wait and the automatic sequence walks through the checklist for you.  Make sure  your sound is turned on and set at the proper level.

 

The X-15A-2 SE saved flights are installed in your "C:\Users\your name\simulator name Files” folder, on your computer or someplace else if you changed the path during the installation.

 

Important – VC only, no 2d panels

 

You must be in the VC view to operate the X-15A-2 SE, it has no 2D panels. The virtual cockpit is available from the "Views" menu item on your simulation platform's top menu bar or by pressing the "F9" key on your keyboard. You can also cycle forward or backward the different views with both the "S" key and the "A" key.

Do not use "CTRL+E" to start the engine! Use the automatic ignition sequence start button (Red magic button on the panel).

Even More Important – Check those simulator settings prior to flight.

 

A week or so ago I loaded up the latest release by A2A Simulations – the Piper Comanche 250.  Well, guess what?  The recommended settings for their Comanche is practically just the opposite of the X-15A-2 SE.  Realism sliders are all full Right, and the auto-mixture must be set to Off, along with a few other specific check boxes set to their specs.  Otherwise the engine will not even start.

When I came back to fly the X-15, everything seems to be a little crazy.  Jep, all my settings were remaining from the Comanche flight.  Lesson learned.

 

Chose to takeoff from the runway or launch at altitude

 

There are two categories of X-15A-2 SE flights: the "takeoff" flights and the (high altitude) "launch" flights. Each category contains fictitious flights and flights that are based on actual X-15A-2 historical missions.

Saved Takeoff Flights

 

Unlike the real X-15 that was designed to be launched at 45,000 feet from a pylon on the right wing of a B-52, the X-15A-2 SE add on can also take off from a runway like any other aircraft in the simulator. Yes, it's not realistic, but, it's a simulation and taking off from the ground is just one more way to enjoy the add-on and is something the real-world X-15 pilots could not do. 

 

The ‘altitude only launch’ for the real X-15 was chosen due to the huge amount of fuel that would be used in climbing up from near sea level in the much denser air.  The fuel guzzling rocket engine would have required about 3 or 4 times the amount of fuel that was carried.  A secondary reason was the throttle controls of rocket engines had not been perfected at that time. (still haven’t)

 

 

After a “takeoff” flight is loaded, click the automatic ignition sequence start button or chose the standard or quick-start procedures to start the engine and take off from the runway.

 

There are four “takeoff” flights included with the X-15A-2 SE add on. Two fictitious flights allow the X-15A-2 to take off from runways located near dry lakes where actual high altitude launches were performed during the real X-15 program. A third flight will permit the fictitious X-15AD-4 to take off from the main runway at Area 51 (Groom Lake). And a fourth flight is provided for inspecting the X-15A-2 on the main runway at Edwards AFB.

 

·         X-15A-2 SE-1 Nellis to Edwards (Takeoff)
X-15A-2 SE-1 ready for takeoff at Nellis AFB just outside Las Vegas. Direct route to Rogers Dry Lake. Landing at Edwards AFB. Fictitious flight (May 18, 1966).

·         X-15A-2 SE-2 Ely to Edwards (Takeoff)
X-15A-2 SE-2 ready for takeoff at Ely Airport. Direct route to Rogers Dry Lake. Landing at Edwards AFB. Fictitious flight (July 8, 1965).

·         X-15AD-4 Groom Lake to Edwards (Takeoff)
X-15AD-4 ready for takeoff at Area 51/Groom Lake. Direct route to Rogers Dry Lake. Landing at Edwards AFB. Fictitious flight (August 19, 1969).

·         X-15A-2 SE-2 at Edwards (Takeoff)
X-15A-2 SE-2 ready for inspection and takeoff at Edwards AFB. Fictitious flight (January 22, 1965).

High Altitude Launch Flights

 

After a high-altitude "launch” flight is loaded and the X-15 is dropped at around 45,000 feet and 0.8 Mach, you need to click the automatic ignition sequence start button or use the quick-start procedures to start the engine and fly the X-15. Hold your heading, fly your mission trajectory, shut down the engine and glide your way back to Rogers Dry Lake, near Edwards AFB (KEDW).

 

By default, the automatic ignition sequence turns ON the unlimited fuel option switch on the service panel. If you prefer a more realistic X-15 flight with a limited engine burn time, you will have to the unlimited fuel option switch to the OFF position before the automatic ignition sequence turns ON the engine master switch. Once the engine master switch is turned ON, the unlimited fuel option switch cannot be changed.

 

There are three high-altitude "launch” flights included with the X-15A-2 SE add on. These flights a designed to replace the B-52 drop and enables the X-15A-2 to be launched at a high altitude over a dry lake that was used for high-altitude launches during the actual X-15 program.  This was typically at 45,000 feet with the B-52 mother ship holding a heading and flying at 500 mph (mach 0.82).

 

·         X-15A-2 SE-1 Delamar Lake to Edwards (Launch)
X-15A-2 SE-1 ready to launch near Delamar Lake. Direct route to Rogers Dry Lake. Landing at Edwards AFB. Flight No. 2-47-84 (August 3, 1966).

·         X-15A-2 SE-2 Mud Lake to Edwards (Launch)
X-15A-2 SE-2 ready to launch near Mud Lake. Direct route to Rogers Dry Lake. Landing at Edwards AFB. Flight No. 2-53-97 (October 3, 1967).

·         X-15AD-4 Bonneville to Edwards (Launch)
X-15AD-4 ready to launch near Bonneville Salt Flats. Direct route to Rogers Dry Lake. Landing at Edwards AFB. Fictitious flight (September 23, 1969).

 

All the X-15 custom aircraft systems are reset when a new X-15A-2 SE aircraft is loaded in the simulator. This is because the X-15A-2 SE add on uses its own proprietary variables in addition the simulator's variables. Unfortunately, FSX or P3D will not remember these custom variables between flights.

 

If the panels appear "frozen" after a new aircraft was loaded while in flight, simply end the current flight and start a new flight with a new X-15A-2 SE aircraft. You absolutely must perform the correct initialization and ignition sequence procedures each time a new X-15A-2 SE aircraft is loaded in the simulator.  That is why I like to use the automatic sequence ignition.

 

Your first mission.

 

In a typical X-15 mission, the rocket airplane is attached under the right wing of a modified B-52 bomber and carried to an altitude of about 45,000 feet. Then, at a scheduled launch time, it is dropped and the pilot fires the airplane's mighty XLR-99 rocket engine to propel the X-15A-2 airplane at several times the speed of sound to high altitude and speed records.

Not counting the climb to the launch altitude (during captive flight), a typical X-15A-2 mission would last for about 10 minutes, of which about 90 seconds (no external tanks) to 150 seconds (external tanks installed) saw the engine burning.

 

A typical simulator mission does not cover any specific experimentation, except for maybe the opening and closing of the skylight hatch to expose the star tracker system to the exterior environment.

After the airplane propellants are exhausted or the engine is shut off by the pilot, the X-15 performs reentry into the atmosphere (if on a high altitude mission) and begins a shallow descent for the final glide to a dry lakebed in the high deserts of California.

 

Some hints, notes, and recommendations

 

Xtreme Prototypes designed and tuned our flight model of the X-15A-2 SE add on with the desktop pilot in mind so we can enjoy our flights and have fun while attempting to control the aircraft in all flight regimes allowed by the simulator.

 

We know that this flight model can’t reproduce the exact flight characteristics of the real X-15 rocket plane, which would be impossible to achieve in our simulators, but they have developed a very unique add -on that is fun to fly while pushing the simulator to its limits and simulating nearly every step and procedure required in a typical X-15 mission.

 

The X-15A-2 SE add-on was designed to simulate rocket propulsion and its related fuel systems including the use of three different propellants and their pressurization methods. Therefore, "CTRL-E" will not work with the X-15 as it does with most conventional aircraft.

 

Instead, you must at the very least power the X-15 from an external source, refuel the aircraft from the service panel, start the APUs and generators, switch on the stable platform in order to have functioning instruments, pressurize the propellant tanks and follow the engine precool, prime and ignition procedures.  Remember: the X-15 is no ordinary airplane!

 

As a short cut or super quick start, we can use the (fictitious) automatic sequence start button on the main panel to start the engine without going through the normal procedures or the quick-start procedures. Following each step presented in the manual might be somewhat more realistic and make your overall X-15 experience more realistic and enjoyable, it is also quite time consuming.

 

When we are taking off from the ground, because there is no B-52 carrier in the simulator to fly our X-15 add on to a proper altitude and heading before launch, we should treat the X-15 as a somewhat ‘normal airplane’  until we reach our intended launch point. This means that we should aim for straight and level flight at Mach 0.80 at FL450 for launch.  Actually, you can use just about any speed and any altitude for launch.

 

Whichever starting method you previously selected, the unlimited fuel option switch, on the service panel, should be moved to ON for this type of practice flight with a takeoff from the ground.

 

You can also use the slew mode or the map view to position the aircraft at launch altitude and speed. Taking off from the ground is fun but, it is something the real X-15 pilots could never do. Using the drop-down Map feature is a super simple method to set location (drag the little airplane icon to your choice of location on the map), type in the speed, heading and attitude and you are ready to go for engine start.  I like to use one of the cardinal headings to make it a little easier to stay on track while waiting for the kick in the butt when the big engine fires.

 

I suggest you use reduced power for the ground takeoff, maybe 75% or so. Accelerate along the runway centerline, ease the nose up and rotate at 275 knots, (everything is faster with this one), using a solid pull-up establish your climb angle at about 35 degrees and watch your speed. Retract your landing gear at his time. You can climb out as steep as you like, but if you allow the speed to build up it will be more difficult to slow down when establishing your launch point setup – your target is level flight and mach 0.80 at FL450. You will want to take your time and not be rushed when getting started at your launch point.  I use the simulator Pause Key often when setting up my missions.

 

The airspeed indicator on the X-15 instrument panel uses a "barberpole" (actually a small red pointer on the left upper side of the instrument) which limits the airspeed at low altitudes to around 690 KIAS. As the aircraft climbs through 26,000 feet, the barberpole pointer moves to allow higher airspeeds thus reflecting the lower air density. It is important that you keep the indicated airspeed below the barberpole value. You will want to study the "Aircraft Reference Information" for other airspeed vs altitude limitations.

 

You can rotate at 260-280 KIAS but try for a smooth but swift pull-up to about 35 degrees nose-up while retracting the gear. You may want to use the pitch error pointer (the small horizontal pointer on the left side of the attitude indicator  and the pitch angle set control knob (a separate instrument located at the lower right corner of the attitude indicator) to fine tune your pitch angle.

 

Before takeoff, select the pitch angle you want with the pitch angle selector control knob (the small lever must be clicked to get positive angles). As you maneuver the aircraft to within +5 or -5 degrees of your selected pitch, the pitch error pointer on the left side of the eight-ball (attitude indicator) will act as a vernier pitch indicator which you can use for fine-tuning the pitch angle. Initial pitch-up and precise pitch angle control was an essential part in every X-15 mission. You should first approximate the desired pitch angle with the ball and then focus on the pointer for precise adjustments. The pointer moves in the same direction as the ball so it acts as a magnifying glass for pitch.

 

Be careful not to take too long to achieve the correct pitch or the airspeed may get out of hand. In this case, you may need to pitch up to very steep attitudes in order to regain airspeed control.

 

As you approach FL450, check your IAS and try to maintain 350-400 KIAS with very small changes in pitch. Remember that you should be holding a heading and trimmed for level flight at Mach .80 and FL450 before fully opening the throttle.

 

Once the launch altitude and speed are attained, you are in position and ready for launch, which only requires setting the throttle to 100% (with the unlimited fuel option switch, on the service panel, to ON) since the normal start-up procedures were performed on the ground.

 

If you want to simulate a true high altitude launch with limited fuel, you have to turn off the engine by moving the engine master switch to the OFF position and perform an inflight engine restart.  You will want to practice these next few steps on the ground to be ready to walk through the restart without losing too much altitude or speed.

 

Set the Unlimited Fuel Option switch to – OFF.
Reset the Engine timer  – Push knob for RESET.
Set Engine Precool switch to – PRECOOL.
Engine prime switch to – PRIME.
Igniter idle switch to – IGNITER. Wait about 10 seconds.
Ready-to-launch switch  – ON.
Throttle – START.  Click and move inboard to 50%.

 

 

Throttle must be at 50% by the time the idle-end (amber) caution light comes on. Combustion in the main thrust chamber of the XLR-99 engine will start almost instantaneously when the throttle lever is moved.

Once again (as during most X-15 missions), you should pitch up to about 30-35 degrees (each mission called for a very accurate angle, which can be set with the attitude indicator's vernier pointer and the pitch angle selector knob) and watch the X-15 accelerate.

 

XP recommends not exceeding 200,000 feet because the simulator has an unpredictable behavior beyond that point. Remember that the highest altitude attained by the real X-15A-2 rocket plane was 249,000 feet (August 3, 1966) and that most high speed flights were performed at lower altitudes. As you become a more seasoned veteran simulator X-15 test pilot you can push the envelope and see just what is obtainable and what will unexpectedly end your flight.

 

Mach 4.65 seems to be a hard limit for speed in the simulator, but I have reached altitudes even higher than any recorded real world X-15 missions. Maybe we can come up with some method to record and post our simulated altitude records.

 

The main instrument panel is provided with a dynamic pressure gauge which allows you to "see" how much air is actually hitting your wings and control surfaces. On the low side of the gauge (low airspeeds or very high altitudes) you see that not much control is possible below 250 psf (hence the high rotation speeds on takeoff). Unfortunately, the ballistic control rockets on the X-15 are not (yet) supported on the current flight simulation platforms, so control at very high altitudes and at very low dynamic pressure are kind of touchy. Be careful not to exceed the maximum dynamic pressure and acceleration values or structural damage and/or "skin overheating" may occur.  You can find these limiting values in the Aircraft Reference Information.

 

During your missions, you can switch over to one of the spot plane views, as visibility out of the cockpit is severely limited at high pitch angles. It also makes for some great screenshots.

 

An engine timer was installed in the X-15 equipped with the big XLR-99 engine. The timer was automatically started during the ignition sequence and would tell the pilot when to shut down the engine, depending on the mission's objectives (altitude and speed to be attained). You can use the engine timer (located on top of the main instrument panel) for the same purpose.

 

If you exclude the climb to the launch altitude (during captive flight), a typical X-15A-2 mission would last for about 10 minutes, of which about 90 seconds (no external tanks) to 150 seconds (external tanks installed) saw the engine burning.

 

The remainder of the flight was jettisoning the empty external propellant tanks, maintaining course while on a ballistic trajectory at several times the speed of sound, holding the correct angle of attack for reentry into the earth's atmosphere, decelerating with the speed brakes, jettisoning the remaining propellants, and finally, gliding your way back home. This is the way you should fly the X-15A-2 SE add on as well.

 

Under normal flight conditions, external tanks should be released as soon as practical after they are empty, at about 70,000 feet and Mach 2.1, in a zero-G normal load factor condition and an angle of attack of about 10 degrees. The external tanks must be released before an attempt is made to jettison internal system propellants.

 

The maximum Mach number to be attained by the X-15A-2 with the external tanks attached is 2.6. The tanks must be released before reaching that speed. This limit is imposed because flight characteristics for this configuration have not been determined for higher Mach numbers.

 

 

 

Get to know the Mojave Desert and the emergency landing sites that this hostile landscape has to offer and try to make it back to Edwards or land on one of the many dry lakes, as your simulation platform provides you with many strips and Air Force bases in the area. Be aware however that at X-15 speeds and altitudes the distances between the landing areas appear quite short and therefore require accurate descent planning. Of course, flat sand does the trick as well, as long as it is not too soft.

 

I suppose the Base Operations Manager might be a tad upset if you just decided to drop in at an AFB for a visit or cup of coffee.  Those skid might do a job on the concrete runway and the Air Base would not likely have any properly equipped towing equipment to move the X-15 off the runway.  Just a thought, but, hey, this is a simulation so have fun.

 

You will most likely want to switch to the trapezoidal windows on final approach, as they allow much better visibility. You will also want to move your view point slightly to the left to better see the runway and you can make the engine timer invisible just to get it out of the way.  The best views for any approach will be to select the invisible canopy mode. This will give you the views of a Mach 6 hang glider.

 

If you are a military pilot you already know how to fly the overhead circling approach, if not, print out one of the graphic illustrations and make your own set of notes for speed and altitude targets.  Just remember, the X-15 will glide, but only at high speeds and at terrific sink rates.  Glider pilots will be familiar with picking a spot, usually slightly short of the touchdown zone and setting up the flare just prior to making contact with the dry lake bed.

 

When approaching the landing site, the remaining propellants must be jettisoned to minimize fire or explosion hazards and to lower the weight of the aircraft. In those cases where you may have had a short engine burn period and you have a long distance to glide, it is a good idea to reduce the weight of the X-15 by jettisoning all the remaining propellant at the beginning of the glide rather than waiting.

 

Approach at 300 KIAS. I like to jettison the ventral (or dummy ramjet) prior to flaps down.  You must jettison the ventral prior to landing to provide the necessary ground clearance for the landing gear skids.

 

With the ventral jettisoned and flaps down, (confirmed by the chase plane) drop the gear at the last possible minute, and just before flare and touchdown at 175-200 KIAS. Try not to over flare and concentrate to keeping the nose aligned with the runway centerline and let the airspeed bleed off as you are sliding along the runway.  Don’t worry about reducing power, or thrust reversers, or spoilers or such – you don’t have any of them.  You do have speed brakes but they are not designed for use in the approach phase.

 

The speed brakes on this airplane are not designed for use as a low-speed drag device. Their design function is to provide necessary drag conditions for control of the airplane at supersonic speeds and relatively high altitudes.

 

As one of the X-15 pilots stated, at this stage of the flight you are just along for the ride, nothing you can do but wait for the plane to come to a stop and the ground crew will pop open your canopy and congratulate you on another successful hypersonic test flight.

 

Here is the full Aircraft Reference Information for the X-15A-2 (taken from the online manual)

 

Aircraft Reference Information (X-15A-2)

 

 

 

 

 

Engine

 

One (1) Reaction Motors XLR-99 "throttable" liquid-fuel turborocket engine

60,000 lbs (thrust)

 

 

Aircraft Weight with External Tanks

 

Launch	51,600 lbs
Burnout (drop tanks jettisoned)	16,500 lbs
Landing (drop tanks jettisoned)	15,600 lbs

 

 

Aircraft Weight without External Tanks

 

Launch	32,250 lbs
Burnout	16,200 lbs
Landing	15,500 lbs

 

 

Speed Limitations

 

MMO – Maximum Aircraft Operating Speed (Mach)	4.65 Mach
Maximum Speed with External Tanks Attached (Mach)	2.6 Mach
VLO – Maximum Gear Operating Speed	300 KIAS
VLE – Maximum Landing Gear Extension Speed	300 KIAS
VFE – Maximum Flap Extended Speed  (40 degrees)	300 KIAS
q – Maximum Dynamic Pressure without External Tanks	2200 psf
q – Maximum Dynamic Pressure with External Tanks	1000 psf
Maximum Acceleration (above 50,000 feet)	8 G

 

 

Mach Limitations vs Altitude

 

10,000 feet	0.8 Mach
20,000 feet	1.6 Mach
30,000 feet	1.8 Mach
40,000 feet	2.8 Mach
50,000 feet	3.5 Mach
60,000 feet	4.0 Mach
70,000 to 100,000 feet	4.65 Mach

 

 

Fictitious Ground Takeoff in the Simulator (standard temperature, sea level pressure altitude)

V1 – Aircraft Takeoff Decision Speed  (51,600 lbs)	250 KIAS
VR – Aircraft Rotation Speed	275 KIAS
V2 – Aircraft Takeoff Safety Speed	290 KIAS

 

 

Simulated Altitude Launch in the Simulator

 

Recommended Launch Altitude	38,000 to 45,000 feet
Recommended Launch Speed	0.75 to 0.82 Mach

 

 

External Propellant Tanks Release

 

Maximum Mach Number with External Tanks Attached	2.6 Mach
Recommended Mach Number for External Tanks Release	2.0 to 2.3 Mach
Recommended Altitude for External Tanks Release	65,000 to 75,000 feet
Maximum Angle of Attack with External Tanks Attached	16 degrees
Recommended Angle of Attack for External Tanks Release	5 to 10 degrees
Normal Load Factor Condition Recommended	0-G

 

 

Altitude Limitations (Typical)

 

NOTE: The highest altitude attained by the real-world X-15A-2 aircraft was 249,000 feet (August 3, 1966).

 

Aircraft Operating Altitude	45,000 to 150,000 feet
Aircraft Ceiling (maximum) Altitude	350,000 feet

 

 

Other Limitations (Typical)

 

Maximum Allowable Rate of Roll

100 degrees per second

 

 

Speed Brakes

 

The speed brakes are not to be used at full deflection below Mach 1.5.

 

NOTE: The speed brakes on this airplane are not designed for use as a low-speed drag device. Their design function is to provide necessary drag conditions for control of the airplane at supersonic speeds and relatively high altitudes.

 

 

Prohibited Maneuvers

 

The real X-15 airplane was restricted from performing the following maneuvers:

 

1. Spin

2. Snap Rolls

3. Snap Maneuvers

 

 

Propellant Jettison

 

NOTE: While approaching the landing site, the remaining propellants must be jettisoned to minimize fire or explosion hazards and to lower the weight of the aircraft.

 

Maximum Speed at 30,000 feet	0.60 Mach
Maximum Speed at 15,000 feet	0.45 Mach

 

 

Ventral (or Dummy Ramjet) Jettison

 

NOTE: Under normal flight conditions, the ventral (or the dummy ramjet) should not be jettisoned except during landing approach.

Maximum Mach Number	300 KIAS or 3.5 Mach, whichever comes first
Recommended Altitude	5000 feet
Minimum Altitude	1500 feet
Maximum Angle of Attack	16 degrees
Maximum Rate of Roll	30 degrees per second

 

 

Landing

 

High Key Point (106 seconds from landing)	15,200 feet, 300 KIAS, gear and flaps up (45-degree bank turn)
180-Turn (82 seconds)	11900 feet, 270 KIAS, gear and flaps up
Low Key Point (58 seconds)	8700 feet, 240 KIAS, gear and flaps up (180 degrees opposite to the runway)
90-Degree Point (36 seconds)	5800 feet, 240 KIAS, gear and flaps up (90 degrees perpendicular to the runway)
Ventral (or ramjet) Jettison	5000 feet, 240 KIAS (lined up with the runway)
Flaps Extended (15 seconds)	3200 feet, 240 KIAS, roll out of turn
Gear Down (10 seconds)	2700 feet, 240 KIAS, 1.29 G pullout
Flare Completed	2200 feet, 174 KIAS
Touchdown (0 seconds)	174 KIAS
VREF - Landing Approach Speed (flaps extended, gear down)	174 KIAS
Aircraft Stalling Speed (flaps up)	140 KIAS
Aircraft Stalling Speed (flaps down)	100 KIAS

 

 

NOTE: The real X-15A-2 aircraft reference information was modified for use in the simulator.

 

Summary and Conclusion

 

What we now have available for our flight simming pleasure is the most up-to-date simulation, using the most up-to-date techniques with high definition textures, custom sounds and animations and even flying models that were proposed but never actually built.

 

 

We can do things with this X-15A-2 SE add on that even the real X-15 pilots could not do, like takeoff from a runway, fly with unlimited fuel, have instruments appear and disappear, change the shape of the canopy or even remove it for a better view.  We can’t fly quite as fast as the later model X-15s did but we can fly higher than any of them.

 

We can use the Saved Flights feature and be ready to go from selected sites, including Groom Lake in Area 51, or other takeoff points or we can simulate a launch at altitude by flying to a target flight level, establishing level flight at Mach 0.80 or so and going to full throttle or we can shut down the engine, reconfigure the X-15, restart the rocket engine and fly realistic missions with limited fuel.  We are even provided a magic red button to automatically configure and start the big rocket engine or we can opt for a start using the normal start checklist or use the Quick Start feature.

We can save our own Saved Flights in addition to those provided.

 

We have retractable landing gear, ability to jettison externally mounted solid fuel rocket boosters, operating flaps and spoilers to assist in gliding to a landing, and removable ventral (dummy ramjets).  We have several models of the X-15, gorgeous delta wing models, white, black, new and well used models to choose from. 

 

We have windows that fog up if not heated, and ablator splatters on the exterior of the windows so we have to close the eyelid on the left pilot’s window and we have some spectacular flame and exhaust effects.

 

We have an outstanding online flight guide with detailed system descriptions and illustrations. This online guide has abundant jump or links and is technically correct for the models provided.  We have additional external links for even more information or background reading.

 

If this is not enough, Xtreme Prototypes has online help for those that purchase the add on as well as patches or updates should they be necessary.

For those that tend to ask, are the systems modeled?  Yes, probably even more systems than you would imagine and all of them at probably at more depth than we normally see.  Just about anything that could be modeled is modeled with sounds and animations, actions for proper use and sometimes reactions for improper use.

 

I think the only major system that is not fully modeled is a working ejection seat and parachute and the B-52 Mother Ship.  Keep in mind that the ejection seat in the real X-15 was never used so it may not have even worked, we will never know.

 

Most of the gauges and instruments are 3d gauges for smooth and visually pleasing use. The developers have tuned the simulation to be sim friendly with removable flight stick, additional large gauges for timing the engine burn time, proper delays for combustion or turbine starts, etc.

 

Just about any switch, knob or lever moves and the tool tips will help you identify the proper switch, gauge, instrument or knob.  Sounds are a big thing here, along with some outstanding visuals such as the solid rocket exhaust flames and main engine rocket burns (60,000 pounds of thrust).

 

Could it be improved?  Oh sure.  A B-52 equipped with the X-15 mounting pylon, the necessary onboard support systems and the notch cut out of the right wing for the vertical stabilizer would be nice.  Maybe a multi-player operation with dedicated B-52 crews could be an additional add on somewhere down road. 

 

I’m not sure we will ever have Reaction Control System dynamics for space flight in FSX or P3d but, something close might be possible one day.  I understand that the X-Plane edition of the X-15A-2 SE could possibly have some enhanced capabilities.

 

I would also like to see the tool tips expanded a bit to not only identify the switch, knob or gauge but to show the active position, such as on or off, engaged, running, idle, 50%, etc.

One last item for the suggestion list is maybe adding some ‘red glow’ along the heated edges during the return from space as it enters the atmosphere.  Certainly not necessary but would be just one more realism feature.

 

Is the X-15 fun and enjoyable to fly? Oh yeah.  For sure.  Very different from your average tube liner or complex single engine GA plane.  A true kick in the butt, hair on fire aircraft, with record breaking hypersonic speeds and altitudes above the atmosphere, with just the proper amount of sheer terror mixed with the long quiet ride home with nothing more than speed and altitude for you to use to place you at your destination. Way fast and way high.

 

 

From the zero g push over at say 30 miles up you can be on the landing strip waiting for the ground crew to pop the canopy with a cold beer or a hot coffee in less than 5 or 6 minutes.  Yep, total flight time from start to finish of a typical mission is about 10 minutes.

 

 

Do I need any special talents to fly the X-15A-2 SE? 

 

Nothing more than you would to fly a simulated Beech Baron, a Boeing 737NG, an F-15E, a Cessna 182 or one of the newer business jets. Crop Duster or Glider experience might give you a slight edge in the flight assignments.

 

This assumes that you will take the time and make the effort to at least skim through the online Flight Manual and read the parts that catch your eye.  When you bump into an invisible wall or things just aren’t going your way, it may be time to hit the books and do a little reading on the subject.

 

I assure you that just because you can fly most of the planes in your virtual hangar you probably can’t complete the simplest mission in the X-15.  The learning curve is steeper for those that want to take the short cuts and not use the checklists or at least read an overview of the task at hand.

 

I spent most of my time getting familiar with the layout of the cockpit and checking back with the layouts and illustrations in the online manual.  I was somewhat familiar with much of the technical terms but didn’t have a clue how and when to operate the basic systems.  Like you might expect, there is an order to the layout and groupings.

 

An item on my to-do list is to fly the X-15 from the VC and also be outside watching as things happen, as a chase plane might see.  This would be useful, for instance, when you jettison the solid rocket boosters.  Sure you hear a ‘furumpt’ sound as you push the jettison button, once all the switches are in the correct position and when you go out to look, sure enough they are gone -not falling away, no parachutes, just gone, poof, outa here.

 

I suppose the simple solution would be to set up a couple of additional views using the view mode and fly from the VC and glance over at the additional windows.

 

You have to pay attention to the task at hand, and there are a few minutes when a lot of things are happening with not much time to look around and contemplate your next move.  Everything happens faster, much faster, when flying at Mach 2+ than compared to flying in the Flight Levels or below.  The X-15 requires constant attention, especially at the really high altitudes.  I found myself rolling left then overcorrecting and rolling two or three revolutions to the right before I got the wings back to level, maybe not level, just stop the rolling.

 

I recommend you learn the flight instruments early.  They are excellent quality gauges and smooth and easy to read.  You just gotta know where to look and what the gauges are telling you about your plane and your flight path.

 

It is certainly easy enough to break off a mission and start over from time to time.  Thank goodness for the saved flights feature.  Don’t be afraid to use the simulator Pause button when you are learning. There is no dual instruction in a rocket airplane.

 

 

 

I have only scratched the surface of all the things you can do and see with the X-15A-2 SE package.  I need to move on to some other pressing projects soon so I am going to close this one up and get the information out so our fellow simmers can truly fly higher and faster.

 

Is there more information available?  Oh yeah.  Try spending a day at the Xtreme Prototypes web site.  Read the available material and watch the slide show.  Download the NASA oversized X-15 poster (pdf) and read everything on it.  Buy a book or two or check out one at your local library or download a Kindle edition and read about the real world X-15 research program.

 

You can pick up some amazing facts and statistics reading these pilot’s books or notes.  I read last night that the total free flight time for all three X-15 airplanes from the start of the project to the 199th last flight was a total of 30 hours 13 minutes and 49 seconds. Wow. Total flight time including captive flight time on the B-52 was less than 400 hours for the 3 planes.

 

That comes to a total in the air time of a little over 130 hours for each X-15.  When the project was over they could have advertised them as ‘Used airplanes, black or white, very low flight time, well cared for and only flown under direct supervision’.  Almost like the low mileage Oldsmobile that was always under cover and only driven by a little old lady to church on Sundays.

I would tell you more, but, I really need to get back in the air.  I mean way up there where you get astronaut wings for a ten minute flight and are home for supper.

 

This one is so unique, so polished and so well modeled and error free, and so complete with all the optional models and the extensive sounds, animations and visuals, not to mention that one purchase includes installers for FSX, FSX-SE, and P3Dv2 that I whole hardly recommend it for those aspiring desktop test pilots.

 

Test System - Xidax X-6 Gaming PC

 

·         Annihilator case, ASUS Z97-A OC mother board
 

·         Intel i7-4790 processor overclocked to 4.4 GHz.
 

·         Corsair Vengeance Pro 2133 MHz DDR3 memory – 16GB
 

·         Corsair RM850W Power Supply
 

·         NVIDIA GeForce GTX 970 – 4GB GDDR5 MSI Reference Overclocked
 

·         2 Performance 512GB SSD, 7 TB additional storage
 

·         Xidax 570LC CPU Cooler
 

·         Windows 7 Professional 64 bit
 

·         Xidax Professional Quiet-Tech sound deadening, PCI wireless, 24X Optical drive combo,
additional card reader for additional USB port connectivity
 

·         Logitech wireless keyboard and mouse, Bose Companion 20 speakers
 

·         Saitek x-52 Pro controllers, Combat pedals.
 

·         Triple Dell 24 IN WS monitors with 5700 x 1200 resolution
 

·         4 Saitek Flight Instrument Panel stand-alone external gauges
 

·         iPad Air for wifi support, Remote Flight cockpit instruments. Maps, etc.

 

Credits

 

Special thanks to Alain Rouleau, the X-Series Producer, for providing the add-on and for responding to my questions about the X-15A-2 SE project and for clearing up some old logon problems at Xtreme Prototypes.

 

Bonus screenshots

 

 

A Runway takeoff and climb out

 

 

 

Some early flights – P3Dv2.5