Known Issues
Xtreme Prototypes X-15AD-4 at Edwards AFB (Prepar3D® v2 screenshot).
As it is always the case with computer software, and especially with addons to existing third-party platforms over which there is limited control, there are some known issues with the current addon version, depending on which simulation platform you are using. Some of these issues are related to the simulator, in which case there is little that can be done from our side, except going around them and expect a fix in the near future. Other issues are related to the addon itself, in which case we are working hard to get them resolved.
We appreciate constructive feedback from our users, so please don't hesitate to report any issue or bug you might have experienced when flying the X-15A-2 SE addon.
To report issues, please fill out our technical support request form.
Please make sure that all the required fields in the form are filled out correctly and provide us with as much information as possible about your technical issue.
Because there are as many computer systems as they are users, you may or may not experience the following issues depending on:
The X-15 moves on the runway at the beginning of a new flight
The engine is running at the beginning of a new flight and before the aircraft was serviced
Unwanted special effects at the beginning of a new flight and before the aircraft has been serviced
Windows® security warning dialogs while installing the software or starting the simulation platform
Some cockpit sounds can be heard from the external views or when the simulation is paused
No volume control to adjust cockpit sounds
"Blue texture flashes" on exterior and interior models, before the addon textures are loaded in FSX
The special visual effects don't look like the ones shown in the documentation
Some special visual effects don't look like the ones shown in the documentation (Prepar3D v2 with DirectX® 11, FSX: Steam® Edition)
The font used in the system monitor panel appear jagged under DirectX® 9 in FSX and Prepar3D® Version 1
The aircraft systems are reset when a new X-15A-2 SE aircraft is loaded?
Rocket-propelled flight characteristics are not accurate in the simulator
No ballistic control at high altitude
Fire extinguishing can be performed only once during a flight
Basic autopilot functions are causing unwanted oscillations at high speed and altitude
Extremely low frame rate when starting a new flight
Saved flights are missing when using Flight Simulator X in another language than English (FSX)
Fire extinguishing can be performed only once during a flight
The rear skids sink into the ground during takeoff
The aircraft cannot be selected in the "Select Aircraft" page, FSX crashes (FSX)
The addon cannot be installed in Flight Simulator X: Steam® Edition
This is a known simulator issue but it probably won't happen with this software version.
By default, the simulator loads the previously saved (or default) flight with the engine of the aircraft running and the parking brake released. In the case of the X-15, it takes a split second for the simulator to "realize" that the rocket aircraft has not been serviced with the necessary propellants and to shut off the engine automatically. Because of the power of the mighty XLR-99 (and the rocket boosters on the X-15AD-4), the initial split second of thrust is enough to move the aircraft along the runway if the parking brake is not set.
(Did you know? The XLR-99 engine's second-stage igniter phase by itself produced 1500 pounds of thrust on the real aircraft.)
To avoid this problem, we recommend loading one of the saved flights included with the X-15A-2 SE addon as a "template" for a new flight. This has the advantage of presetting all X-15 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 with the parking brake released in the previous flight, in the last saved flight or in the default flight.
As an alternative, you can also create a new flight with a single-engine stock aircraft (one that comes with the simulator), turn off the engine ("CTRL+SHIFT+F1") and set the parking brake ("CTRL+.") . Replace the aircraft with the X-15A-2 SE and go to Edwards AFB (or any other runway of your choice), apply the parking brake, and save this flight under a different name. Simply load this saved flight (or make it your default flight) each time you want to fly the X-15A-2 SE.
While highly improbable in this software version, if the engine was not shut down automatically by the X-15 integrated systems after the flight was loaded, simultaneously press the "CTRL+SHIFT+F1" keys on your keyboard to shut down the engine and apply the brakes to stop the aircraft on the runway. Set the parking brake ("CTRL+.") after the aircraft has stopped moving.
To avoid this problem, we recommend loading one of the saved flights included with the X-15A-2 SE addon as a "template" for a new flight. This has the advantage of presetting all X-15 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 with the parking brake released in the previous flight, in the last saved flight or in the default flight.
As an alternative, you can also create a new flight with a single-engine stock aircraft (one that comes with the simulator), turn off the engine ("CTRL+SHIFT+F1") and set the parking brake ("CTRL+.") . Replace the aircraft with the X-15A-2 SE and go to Edwards AFB (or any other runway of your choice), set the parking brake, and save this flight under a different name. Simply load this saved flight (or make it your default flight) each time you want to fly the X-15A-2 SE.
While highly improbable in this software version, if such effects are visible, perform the following procedure to turn off the unwanted effects:
Refer to "Special Visual Effects" for more information.
In addition to many other files, important software components need to be installed on your system for the X-15A-2 SE addon to function. These are contained in special software libraries called DLLs that are copied to the addon's panel folder during the installation process. You must answer YES (or RUN) when asked by Windows® or your simulation platform if you trust these modules and allow them to be installed and to run on your computer.
Standard Windows® security warning dialogs will appear on your desktop and in your simulator's main window the first time your run your simulation platform after installing the X-15A-2 SE addon. Click the "YES" button (or the "RUN" button) when these dialogs appear. The dialogs will appear only once.
IMPORTANT: The X-15A-2 SE addon will not work without these modules. You must allow them to be installed.
Refer to "Installing your Addon".
In addition to the basic aircraft sounds that are controlled by the simulator's own sound engine, the X-15A-2 SE addon features more than 50 extra sound effects, mainly cockpit sounds, that are managed by the addon's special systems and played by a third-party sound module. Due to software limitations, some cockpit sounds can still be heard from the external views or when the simulator is paused. Volume adjustment in the simulator has no effect on these sounds (see next topic below). This has no impact on the overall simulation.
While we took great care to adjust the extra cockpit sound effects individually so they fit well in the overall sound mix, there is no separate control to adjust the volume of the extra cockpit sounds in this software version. This is mainly due to limitations in the current simulation platforms. However, it is possible to balance the extra cockpit sounds with the basic aircraft sounds that are controlled by the simulator by using the master volume control of your computer sound system. First, adjust the master volume on your computer so that the cockpit sounds are at a correct level. Cockpit sounds can be heard by clicking some of the switches, levers and knobs in the virtual cockpit. Then adjust the basic aircraft sounds in the "Settings – Sound" page, under "Volume Levels" for the proper balance. This has no impact on the overall simulation and needs to be done only once.
This is a simulator issue. If you experience "blue texture flashes" in FSX while the addon textures are loading, especially when in the virtual cockpit, we recommend disabling the DirectX® 10 Preview option in your Display settings (Graphics tab). FSX seems to perform better under DirectX® 9. Third-party free DirectX® 10 shader fixers are also available in FSX forums. Note that a small delay (especially on slower computer systems) before the addon textures are loaded is normal on the current simulation platforms, especially when loading high-resolution textures. For more information, refer to "Recommended Settings for Flight Simulator X".
The special visual effects (engine flames, contrails, APU exhaust, etc.) included with your X-15A-2 SE addon should look like the ones shown on the product page and in the documentation.
For reasons that are sometimes hard to define, special effects appearance may vary from system to system, depending on many factors including your simulation platform, your frame rate, your version of DirectX®, your view aspect ratio and your graphics hardware and settings. If, after trying different settings (see "Compatibility, Performance and Settings"), you are still not satisfied with the effects on your system (for example, they are too big or too small), try replacing the special effect files.
Visit the "Downloads" section on our website and download the Special Effects Package. Try the different effects by copying them to your "... simulator name\Effects" folder. Read the instructions included with the Special Effects Package.
Please note that this is no longer an issue with the new addon version for Prepar3D® v4.
Refer to "Special Visual Effects" for more details and options.
This is a simulator issue that is purely cosmetic and has no impact on the overall simulation.
The special effect engine was changed from CPU to GPU with the release of Prepar3D® v2. This has the advantage of freeing computer resources and improving performance on high-end graphics hardware. The X-15A-2 SE special visual effects were upgraded to conform to the Prepar3D® v2 specifications. While the new Prepar3D® v2 particle effects are visually identical to the FSX/Prepar3D® v1 effects, there is a simulator issue affecting extrusion effects that still needs to be resolved. Until then, extrusion effects such as engine contrails, wing vortices and vaportrails, APU exhaust and propellant jettison effects at high speed and altitude may appear sawtoothed, wrongly oriented, faded, with repeating arrow patterns. This is normal until a fix is made available.
For other reasons, we noticed a similar issue in FSX: Steam® Edition, to a lesser degree. This is normal until a fix is made available.
Please note that this is no longer an issue with the new addon version for Prepar3D® v4.
Refer to "Special Visual Effects" for more details and options.
This seems to be a minor simulator issue. Fonts appear normal under DirectX® 9. We don't know of any fix at this time. This is not an issue in Prepar3D® v2 and later.
This is a simulator issue. Some systems are reset, but not all. This is because the X-15A-2 addon uses its own proprietary internal variables in addition the simulator's variables. Unfortunately, due to software limitations, these custom variables are not memorized by the simulator 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 the new X-15A-2 aircraft. Note that the correct initialization and ignition sequence procedures must be performed before flight each time a new X-15A-2 SE aircraft is loaded in the simulator.
At the time of publication,rocket engines were still not supported in either Microsoft® Flight Simulator X or Lockheed Martin® Prepar3D®. Your simulation platform still sees the X-15A-2's XLR-99 engine, and the solid rocket boosters on the X-15AD-4, as jet engines. Rocket-propelled flight is therefore not 100% accurate in the simulator although we tried our best to emulate it as much as we could in the flight model, considering the present limitations.
We sincerely hope that all simulation platforms will offer support for rocket engines (and ballistic control) in the near future.
At the time of publication, ballistic control for rocket airplanes was still not supported in either Microsoft® Flight Simulator X or Lockheed Martin® Prepar3D®.
We sincerely hope that all simulation platforms will offer support for rocket engines (and ballistic control) in the near future.
Because aerodynamic control surfaces become less and less effective above about 125,000 feet in the simulator as dynamic pressure decreases, we recommend flying the X-15A-2 addon below 200,000 feet. Note 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 even lower altitudes. The simulator will still give you limited control at high altitudes, but flying will become more challenging.
We found that the best way to complete a ballistic trajectory at high altitude is to level off and maintain heading after the engine is cut off. Eventually, the aircraft will lose altitude until the control surfaces become effective again. For more information about this technique, refer to "The X-15 Experience".
This is a simulator issue. The flight needs to be reset or a new flight initiated for the simulator's extinguisher to recharge.
This is a simulator issue in both FSX and Prepar3D® v1. It is no longer an issue in Prepar3D® v2 and later. The flaps seems to work according to specs on all simulation platforms.
We noticed that some of the simulator's basic autopilot functions such as "wing leveler" and "altitude hold", when engaged, induce unwanted oscillations at very high speed and altitude (instead of helping the pilot). Unfortunately, we have no other solution at this time but to recommend disengaging these functions when such behavior is encountered until a fix is found.
Please note that this is no longer an issue with the new addon version for Prepar3D® v4.
We noticed that occasionally, and for no apparent reason, the frame rate would drop significantly at the beginning of a new flight in FSX. This would be clearly noticeable in the virtual cockpit. Of course, this is not normal and we believe it is a simulator issue, not an addon issue. It may occur when many changes are made at the beginning of a new flight, like changing the time and season and switching aircraft several times. If you didn't experienced slow rate issues with the X-15A-2 SE addon before, simply reset the flight. If the issue is still not resolved, refer to "Compatibility, Performance and Settings".
This is the normal "hog calling" like noise of the X-15 rocket engine being shut down by the addon's special systems. So why was the engine fired in the first place? Because the simulator has the bad habit of starting the engine when positioning the aircraft in mid-air with the map or with the slew commands. In the case of the X-15, which requires special procedures to start the engine, this isn't a good idea. So that's why the addon needs to shut down the engine, which produces this unique sound. This has no other impact on the simulation.
This simulator issue has been resolved during the beta tests. However, if some parts on the external model are missing after loading a saved flight from the Free Flight page in FSX with the same aircraft that appear in the aircraft preview window, resetting the flight will return things to normal. Loading the same flight from the top menu bar did not create any issue so we don't know at this time what might have cased this anomaly.
It is normal to see the ball nose moving in the direction of the wind, but not in an exaggerated manner.This seems to be a simulator issue that cannot be resolved at this time. The effect disappears when the aircraft is airborne. This affects the ball nose and the angle-of-attack and side-slip indicators in the cockpit.
If you are using Flight Simulator X in another language than English, you will need to manually move the saved flights from the "C:\Users\your name\Documents\Flight Simulator X Files” folder to your "C:\Users\your name\Documents\Flight Simulator X Files in your language” folder. This is because Flight Simulator X changes the name of your saved flight folder, depending on your language. For example, while the folder name "Flight Simulator X Files" is used in English, it becomes "Fichiers Flight Simulator X" in French. The installer cannot detect the language of your simulation platform so you will have to copy or move the saved flight files manually. This is not an issue in Prepar3D®.
Setting the local time with the aircraft clock sometimes produces unexpected results in FSX, including freezing the screen while the simulator is updating the environment and traffic. If you experience such an issue on your simulation platform, we recommend changing the local time on the "SELECT TIME AND SEASON" page in the simulator (available from the "World" menu item in the top menu bar) instead. This seems to be a minor simulator issue and we don't know of any fix at this time. We did not encounter this issue in Prepar3D®.
The landing gear is configured so it (and the aircraft) sits properly on the ground on most hard surfaces such as a concrete runway or a dry lakebed. However, it is normal for the landing gear to be partially buried into the ground or even to "float" above it if you land the aircraft on a rough, soft (sandy) or uneven terrain, for example, after an emergency landing somewhere in the desert. This also depends on the resolution of the mesh on which it sits. It all cases, this is a terrain issue and not an addon issue.
The X-15 was not designed for a normal takeoff from the ground. Because of the position of the rear landing gear relative to the center of gravity, it is normal for the rear skids to sink slightly into the ground when the airplane takes off, especially if you pull back too much on the center stick.
It's been reported during the beta tests that some third-party addons or FS utilities may interfere with the correct installation of the X-15A-2 SE addon. These programs may also alter the appearance of your add-on aircraft by modifying the textures and the materials in the model files. If the different X-15A-2 aircraft variations are correctly displayed in the "Select Aircraft" page but you are unable to select any one of them, or worse if selecting them causes FSX to crash, suspect such third-party programs. For unknown reasons, these programs may prevent the addon's system DLLs from being "trusted" by FSX and the addon will not work. Remove these programs to solve the issue.
Also, depending on security settings and permissions in Windows® VistaTM, you may not be able to install critical software components (DLLs) and the addon will not work. We are sorry we cannot support this addon if installed under Windows® VistaTM or Windows® XP®. Windows 8.1/8/7 is required in order to install and operate this addon (see "Minimum System Requirements").
Please do not use the standard installer for FSX! A special installer for FSX Steam® is available from our "Downloads" section (free for registered users).
Please note that FSX: Steam® Edition is installed in a different way to the boxed version and occupies a different location on your computer. With the standard installer for FSX, you will need to specify a different path/root folder during the installation process to deploy the addon into FSX: Steam® Edition (by default: "C:\Program Files (x86)\Steam\steamapps\common\FSX").
Also, with the standard installer, you will need to copy the saved flights from the "C:\Users\your name\Documents\Flight Simulator X Files” folder to your "C:\Users\your name\Documents\Flight Simulator X - Steam Edition Files” folder. This is because FSX: Steam® Edition uses a different folder to store your saved flights.
For these reasons, we recommend using the new installer for FSX: Steam® Edition.
Refer to "Installing your Addon" for more information.