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Are pilots allowed to intentionally crash inside the simulator? It is good for stress relief and seems like a fun way to do something you would never do on an actual aeroplane, with little to no consequence.

If not, why not?

Vikki
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56independent
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    I've done it in the shuttle simulator, when I was testing out a fix for the sim crashing at too high of an altitude on contingency aborts. But I am not a real pilot. – Organic Marble Jul 27 '21 at 19:29
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    IIRC some C130 simulators in the UK in the late 1970s used a video camera to capture real-time images of a landscape model - seems rather primitive by today’s standards but there you go. If a pilot crashed into something it would cause damage to the camera and landscape, so it was frowned upon. – Frog Jul 27 '21 at 19:48
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    What type of simulator are you asking about - Advanced full flight/full motion simulators or lower end Flight training devices? –  Jul 27 '21 at 19:59
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    I am referring to physical simulators, with real buttons, and not a FlightGear and laptop setup (which I use daily). – 56independent Jul 27 '21 at 20:09
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    Does this answer your question? Do Flight Simulation Instructors stop the simulator before a simulated crash? – BtureP Jul 27 '21 at 20:41
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    No, as that is for accidental crashes, and not ones done on purpose. – 56independent Jul 27 '21 at 20:59
  • Flight training device still has all the realistic controls and switches but, unlike full flight simulator, it does not move. – Jan Hudec Jul 28 '21 at 05:03
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    As a layperson I'd be concerned if pilots were being conditioned to crash a plane (even a fake one) to "blow off steam". – Joe Sewell Jul 28 '21 at 16:05
  • Just a clarification - do you mean for the pilot to crash the simulated plane, or for the simulator to physically run out of travel and crash into a hard stop ? – Criggie Jul 28 '21 at 19:31
  • If Andrew Wiggin had intentionally crashed in the simulator, that would have been rather awkward. – Acccumulation Jul 28 '21 at 19:38
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    @Criggie I mean that the pilot regardlessly decides to crash, with no regard to simulator specifics. – 56independent Jul 28 '21 at 21:43
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    As real simulator hours are expensive (and probably supervised), I highly doubt that an pilot crashes for fun. However the situation may be completely different for home simulators. Maybe watch the excellent movie "Sully (also known as Sully: Miracle on the Hudson)": Crashes are no fun for pilots. – U. Windl Jul 29 '21 at 09:58
  • If a pilot (or even a trainee pilot) doesn't understand the difference between real-life aviation and playing video games, maybe their license should be revoked until they demonstrate they are psychologically well enough to fly. – alephzero Jul 29 '21 at 11:58
  • The Department of Homeland Security might want to keep a eye on a pilot training like that. – Quora Feans Jul 30 '21 at 23:18
  • I have heard that the FAA actually frowns upon this ever since 9/11. Some instructors also used to place pilots in unrecoverable windshear situations during training, but then it was decided that this is not a positive training scenario, and could reinforce incorrect attitudes regarding windshear. – Lnafziger Sep 10 '21 at 05:16

6 Answers6

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I've intentionally crashed Full Flight Simulators, to demonstrate to the instructors that in a modern day FFS, crashing is a non-event. Basically just a stop of the real-time equation computations, a bit of a crash sound, and freeze of the visuals. The instructor then selects a new initial position, the sim resets at this position after the normal time period, and the training continues.

During normal flight training when type rated pilots demonstrate their skills in handling emergencies to prevent a crash, this does not happen of course. Unintentional crashes can take place during the type rating courses, when pilots who just graduated on a propeller plane are getting used to the speed of control and decision making of a passenger jet.

Yes indeed, crashing an older type sim could have lengthy consequences if the computers needed to be re-booted upon a crash. Not anymore.

Note: I'm talking about modern simulators with electric motion and control loading. Any event that kicks a hydraulic system off-line needs fade-in time for the re-engage.

Koyovis
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    I would also like to state that even in 'very' modern simulators (I work on cutting edge fighter pilot systems), mission computers are re-hosted on PCs. they often don't like being reset. crashing often means a full reset which sometimes can take up to 15 (or more) mins. It happens every day. Sometimes on purpose. But this type of behaviour isn't limited to just "older type sims". Doesn't mean it 'needs' to be that way but it is that way still – g19fanatic Jul 28 '21 at 15:56
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    The ones I”m talking about had industrial PC host computers. A crash was handled in the software: detection of a sudden spike in flight path, upon which the flight dynamics computations were frozen, then re-initialised by the instructor. Never did the host need to reboot. – Koyovis Jul 28 '21 at 23:43
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    @Koyovis, the problem sometimes happens when the real firmware or complete sub-systems are used in the simulator. They are rarely designed to "understand" crash (or even "pause" for that matter), and might not continue correctly without a reset. – Zeus Jul 29 '21 at 02:28
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    I've heard of pilots taking an hour the last day of training practicing crazy engine-out takeoff scenarios where you're lucky to make it back to the runway. Sounds like a fun end of the day energy-management challenge where most people fail. – Nate Lowry Jul 29 '21 at 02:43
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    @NateLowry Yeah I did that in the 737NG simulator, crazy scenarios in a steep dive with the engines at idle, then start the pull-up at exactly the right moment for a neat touchdown. Part of a bet that I could get the plane on the ground faster, did so by touching down at the point where I took off, against the take-off direction, which is against standard practice of course. Can only be done in a sim. Exciting rides. – Koyovis Jul 29 '21 at 04:13
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    @Zeus The sim had aircraft hardware on board, I specifically remember the Honeywell EGPWS box. The sim was just tested and set-up specifically for minimum initialisation time no matter the pre-condition. We did not have to re-boot between training sessions. – Koyovis Jul 29 '21 at 04:34
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One reason to deliberately crash in a simulator is to reconstruct an accident.

This happens once in a while during an accident investigation, as it's less dangerous (obviously) than trying to reconstruct the conditions of the accident in a real aircraft (if possible at all, as the investigators of course can't control the weather outside of the simulator.

But that's not done for fun, to blow off steam, or some other "I feel like it" moment by a pilot.

Toby Speight
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jwenting
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    It certainly might be useful and justified to find the conditions that led to a crash, but even then, I doubt that someone would deliberately crash it. It would be at most one more case of "this might have caused the crash". As far as crashing "for the hell of it", I'm sure that whoever is paying for your time on the simulator (i.e., your airline employer) would not be amused. I suspect that the licensing authorities would not look kindly on the mental stability of a pilot who appears to be possibly suicidal (see GermanWings crash). – Phil Perry Jul 28 '21 at 14:49
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    @PhilPerry deliberately recreating the exact conditions that caused a previous crash is IMO deliberately crashing. As the people doing it have good reason to do so their mental state won't be questioned if they do it in the context of investigating that previous crash. – jwenting Jul 29 '21 at 06:15
  • jwenting, my point is that investigating why a crash happened may well result in a crash (as in real life), but hopefully the tester can work their way out of it ("it might have been avoided if the pilot had done X"). That's NOT deliberately crashing. As for doing it deliberately, I would hope that the simulator operator would report to the authorities anyone who seems to be crashing for no real cause, as they are obviously mentally ill. Note that's different from pushing the envelope or practicing in unsafe conditions. – Phil Perry Jul 29 '21 at 14:37
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    @PhilPerry the investigators will run the scenario several times. First using the exact inputs they found the actual pilots used (if known) and then trying different things that might have prevented the accident. – jwenting Jul 29 '21 at 14:57
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    I think I read that during the final real airworthiness test flights of the 737-Max, post-fixes, the pilots attempted to recreate a situation similar to the fatal crashes. – Mark Stewart Jul 29 '21 at 17:27
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Advanced full flight/ full motion simulators are extremely expensive (can be in the Millions $$) and are very expensive to operate. In an Air Carrier ( or similar) training and testing environment these Sims can be scheduled 20 hours (or more) a day. Usually training and testing procedures/profiles are so packed with maneuvers there is little time for random activities outside of the mandatory syllabus or testing requirements.

Often, when one of these simulators crashes in the course of training or checking (which in my experience is not common) it goes "off motion" abruptly causing some stress to the hydraulic components and requires a reboot of its systems that utilizes valuable time.

Likely people have crashed these types of simulators on purpose, but for the reasons I note above, I doubt it is done very often.

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    The vast majority of sim crashes are "unintentional" for sure: I would say loss of control during V1 cuts on rotation and screwing up terrain avoidance or wind shear escape situations. – John K Jul 27 '21 at 22:38
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    Good answer. A couple nights ago I had a hard landing on a no-flap approach and it dumped the motion. It's tough on the machinery... crashing wouldn't be something you would do for fun, although I have flown under bridges in military simulators, so you can have some fun occasionally. – Michael Hall Jul 28 '21 at 05:06
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    If such machinery is so expensive, then why didn't they install any failsafe to protect the machinery from damage, in such cases. Why should it stop "abruptly"? It could be designed to limit acceleration and deceleration to safe values. – vsz Jul 28 '21 at 09:49
  • @vsz it sounds like stopping abruptly is how it prevents damage. – Tim Jul 28 '21 at 10:04
  • @Tim why would gradually stopping cause damage? – user253751 Jul 28 '21 at 10:05
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    @vsz The few seconds before a crash are extremely important. There could still be a way to save the plane and passengers, so the simulation should be as faithful as possible. When would you begin to limit acceleration and deceleration? – Eric Duminil Jul 28 '21 at 10:06
  • @user253751 stopping gradually wouldn’t damage it, but leaving buffer for it to be able to gradually stop reduces the operational range. I’d imagine you want to be able to push it right to the limits in normal operation. – Tim Jul 28 '21 at 10:24
  • @Tim I'd imagine the computer is smart enough to predict the future enough to leave enough buffer. Do simulators generally get damaged from high-g maneuvers for example? – user253751 Jul 28 '21 at 10:31
  • @user253751 there’s a physical limit. It can predict the future, sure, but any buffer left is a trade off. I imagine plenty of simulators simple don’t do high g manoeuvres – Tim Jul 28 '21 at 10:41
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    @Tim they could also choose to simulate the crash without any physics: the screens could go dark and the simulator could continue simulating perfectly straight and level flight (or whatever the last attitude was) through the ground, until it's turned off or reset. If it can simulate straight and level flight above the ground without damage, it can also simulate it below the ground without damage, since the ground level is just a computer fiction. – user253751 Jul 28 '21 at 10:46
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    @EricDuminil: At all times, the simulator could determine--given the present state of hydraulic valves and the positions and velocities of all parts of the real-world system, some combinations of motion actions would be able to safely bring the mechanics to a stop without hitting any mechanical limits if the mechanical action requested by the physics simulation were performed. If no such sequence would exists, check the list of "escape action sequences" that exist from the current state and perform the first action of one of them (preferably the one that would best match the physics). – supercat Jul 28 '21 at 17:30
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    We had all kinds of safing devices and software limits on the motion system in the shuttle mission simulator. There were leg extend/retract speed limits, kill switches at 90% of full leg extension, etc, etc. This was all above and beyond the checks in the physics models that would "crash" you if you pulled too many g's, penetrated the ground with the gear up, overloaded the gear, etc, etc. – Organic Marble Jul 29 '21 at 02:03
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    The sim knows where the ground is. Just a matter of writing pre-emptive crash code. – Koyovis Jul 29 '21 at 14:21
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For a specific example where multiple tests were done in a simulator that resulted in "crashes", see the Miracle on the Hudson:

From Wikipedia (which has references to NTSB and other reports), emphasis added:

The NTSB used flight simulators to test the possibility that the flight could have returned safely to LaGuardia or diverted to Teterboro; only seven of the thirteen simulated returns to La Guardia succeeded, and only one of the two to Teterboro. Furthermore, the NTSB report called these simulations unrealistic: "The immediate turn made by the pilots during the simulations did not reflect or account for real-world considerations, such as the time delay required to recognize the bird strike and decide on a course of action." A further simulation, in which a 35-second delay was inserted to allow for those, crashed.

See also United 232.

manassehkatz-Moving 2 Codidact
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    But they didn't "intentionally crash" in the simulators, did they? – Bianfable Jul 28 '21 at 19:48
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    Not truly "intentionally crash". But my impression is that they went into the simulation knowing there was a high probability of crashing. Not exactly what the question asked, but similar to jwenting's answer, with specifics. – manassehkatz-Moving 2 Codidact Jul 28 '21 at 19:55
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    Welcome to Av.SE. That's a good example of a case when the pilots were entirely willing to "crash the simulator" for an entirely valid reason. I agree that it's a good answer to the question. – Ralph J Jul 28 '21 at 21:18
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    Crashed, in this case meaning: did not make the runway. – Koyovis Jul 28 '21 at 23:52
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    @Koyovis In the case of the Hudson, the real pilots did not make the runway, but they didn't crash, they performed a controlled ditching. But the simulations mostly resulted in (simulated) crashes. – manassehkatz-Moving 2 Codidact Jul 28 '21 at 23:53
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I work in a company that builds simulators. Our customers have a lot of expectations, so we work hard to make the simulation adequate. The precision of the simulation of a crash is not, by far, what is most expected from our simulators. So we do not waste our time making it somewhat realistic. Moreover, to check that a simulation is realistic, it is compared to real aircraft behaviour. We do not find easily data for crashes to compare with, hopefully. So, for our sims, this non-realistic feature is just here to inform that the aircraft can't fly anymore and that the lesson should be resumed.

SR_
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    I agree that professional flight simulators don't focus on "post-crash" simulation like fancy explosions and other animations that might be considered as "fun", but on "pre-crash" simulation (events that lead to a crash). Maybe those simulators even abort before the pane (or parts of it) hit the ground. Also I think it's a very hard part to simulate equipment failures is great detail. Maybe have a look at X-Plane: It may be some fun to do a "power slide" on the runway with an airliner, but it's most likely not realistic (as the tyres would be pulled off, I guess). – U. Windl Jul 29 '21 at 10:13
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    Why would a professional flight simulator (or the company that builds one) want to reproduce game like effects (ala xplane). That's not what those simulators are for. – CGCampbell Jul 29 '21 at 14:21
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    While most simulators don't try and specifically replicate crashes, I have seen both developers and customers decide they need to "just see what happens when the plane crashes". It is one of those things a lot of people will want to try. – Dragonel Jul 29 '21 at 18:23
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    Landed a sim of an aeroplane type I had not flown before a couple of months ago. My touchdown would have been too impactful on the landing gear, the sim conveyed this by freezing the visual and playing a crash sound. Then I could re-initiate to the glide slope to try again. The sim was built in 1993 - it had no problems with a hard landing crash, it only showed me that my landing skills need to be improved on this AC type. – Koyovis Jul 30 '21 at 07:05
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Not aviation, but simulator related. In the 1960s the UK railways were transitioning from steam traction to electric and diesel. A lot of steam drivers needed retraining. They had to unlearn a lot of things to do with the 'feel' of the train in motion. A simulator was built, with a replica locomotive cab, with a movie screen in front. On this was projected a film of the route being trained. A mainframe computer was programmed to read the cab controls (speed and brake) to control the film speed, show appropriate readings on the dials in the cab (speed, brake air pressure, motor amps, etc) and also move the cab via hydraulic actuators in accordance with the calculated motions expected due to acceleration, deceleration, rounding curves, passing over switches, etc.

One driver, allegedly, braked too late at the end of a run in a terminal station with buffer stops, and the computer faithfully moved the cab in accordance with the deceleration, breaking the driver's nose against the windscreen.

Michael Harvey
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  • It can't have moved the cab exactly in accordance with the acceleration and deceleration of a real locomotive - if it did then it would be a real locomotive. – bdsl Jul 30 '21 at 09:11
  • @bdsl of course it didn't mimic exactly to the extent of replicating a collision authentically. That would be pointless, and if it did, a trainee driver might seriously injured or killed. – Michael Harvey Jul 30 '21 at 22:59
  • I wasn't so much thinking about not mimic to the extent of a collision - I was more just thinking not mimicking the acceleration to the extent of actually travelling from one end of the UK to the other. – bdsl Jul 30 '21 at 23:25