15 ms·

In two incidents, F-16 aviators were rendered unconscious, but saved by software

214 points by prostoalex 6y ago

jcims 6y ago
I would guess that the presence of AGCAS is, in part, why the pilots were willing/allowed to push themselves so hard in training. I didn’t really say if the system only intervenes if it believes the pilot is unconscious or if it always intervenes if the fligh path is within some envelope of terraforming.
- saberdancer 6y ago
  I doubt they changed their training methods due to AGCAS. From my understanding, system works automatically and does not take into account whether pilot is conscious or not. It is not meant just to save unconscious pilots but also those who are disoriented (in fog, confused, ...). Given that it is a military aircraft, it's likely the system can be turned off if deemed necessary, for example if you are avoiding a missile it might be less risky to dive close to the ground than to pull up.
  - Kolokius 6y ago
    I would guess there are two possibilities. The system won't override pilot input or the system only kicks in when it's 100% certain that a crash is inevitable. > If the system predicts an imminent collision, an autonomous avoidance maneuver—a roll to wings-level and +5g pull—is commanded at the last instance to prevent ground impact.” Sounds like by the time the system kicks in, you probably need it to kick in.
    - darkerside 6y ago
      Engineering doesn't typically work this way. There needs to be a tolerance because you can't account for all variables. The question really is, at what probability of likelihood of a crash do you want to attempt to avert it? Averting 99.5%+ of crashes probably eliminates flexibility beyond what is appropriate for a fighter pilot.
      - Kolokius 6y ago
        > “Auto-GCAS continuously compares a prediction of the aircraft’s trajectory against a terrain profile generated from onboard terrain elevation data. If the predicted trajectory touches the terrain profile, the automatic recovery is executed by the Auto GCAS autopilot. The automatic recovery maneuver consists of an abrupt roll-to-upright and a nominal 5-G pull until terrain clearance is assured.” https://sofrep.com/fightersweep/in-the-seat-with-agcas-those-lost-and-those-saved/ https://sofrep.com/fightersweep/in-the-seat-with-agcas-those... It predicts a trajectory. Either that trajectory looks like it'll hit the ground or not. If it doesn't, then there's no need to intervene.
        aflag 6y ago
        Any nose dive will look like it will hit the ground, won't it? The question is at which attitude does it need to pull up. Obviously, there are many factors involved, but there may be other factors the system is not aware of, that's why it probably makes sense that's overridable. I bet there is a way to do it.
        jsmith45 6y ago
        It is mostly likely timing based. It may well calculate how much time is left until collision, or perhaps until a 5G pull will become insufficient to recover. When that time remaining drops below N seconds (which from looks to be perhaps 1-3 seconds if it is the until insufficient time metric, or perhaps an extra few seconds for time until collision) it will activate. Obviously there are other criteria to prevent a landing approach from being seen as an imminent crash etc. But an override system that cannot be accidentally held by a disoriented or unconscious pilot seems plausible.
    - jcims 6y ago
      There’s a short article here with a little more detail, sounds like it overrides pilot input as well (i.e. ‘nuisance flyups’) https://sofrep.com/fightersweep/in-the-seat-with-agcas-those-lost-and-those-saved/ https://sofrep.com/fightersweep/in-the-seat-with-agcas-those...
    - dTal 6y ago
      By the time it's 100% certain, there's nothing it can do. Any control input the system can make, the pilot could also be theoretically planning to make.
      - Kolokius 6y ago
        I didn't say "it's 100% certain that no matter what, there'll be a crash". Implied is that "100% certain of an impending crash without any extra input".
      - jki275 6y ago
        AGCAS was developed because pilots in the F16 specifically were blacking out from excess G forces and flying into terrain. An unconscious pilot isn't likely to make any useful control input at all.
        jcims 6y ago
        Watching people convulse as they recover from GLOC in simulators makes me think that pilot input is probably best ignored.
- rcxdude 6y ago
  I doubt this is the case: the system was developed in part because blackouts were one of the leading causes of deaths during training.
hoseja 6y ago
"the system consists of a set of complex collision avoidance and autonomous decision making algorithms..." It's 50 nested ifs, isn't it.
- mhh__ 6y ago
  Actually - I sort of want to work in defense for a few years to find out, that and the sheer amount of tech in a modern missile (the fact that they would likely be used is why I didn't apply) - I reckon most the algorithms here are basically finely tuned signal processing and other non-"AI" processes. There's a tendency to think that everything that isn't completely ab initio like machine learning is bad or inelegant - I often fall for this trap myself, but to just get the job done you can get a very long way with "dumb" algorithms and a practically infinite budget.
  - pjc50 6y ago
    The advantage of the "old" control systems approach is that it's not a black box; you can reason about its behavior across the state space and make assertions about its frequency response and stability conditions. (Is a neural network really different from a very large cascade of nonlinear filter elements?)
    - BrianOnHN 6y ago
      > Is a neural network really different from a very large cascade of nonlinear filter elements? It's different in theory, but not by much practically. Reverse engineering the former is a fool's errand, but so would be a sufficiently complex version of the latter. In terms of Kahneman's "Thinking Fast and Slow," ML, at least in its current stage, is like the fast thinking system. It's essential but is exponentially more valuable when combined with the slow system, which is still elusive in AI practice.
    - mhh__ 6y ago
      Indeed. I'm just kind of fascinated by military technology e.g. The F/A-18's cockpit HMDs and Hud were light-years ahead of anything in star wars with the exception of holograms even in 1983.
mothsonasloth 6y ago
Just reminded me of this video of G-LOC https://youtu.be/s0Xgff1NsL0 https://youtu.be/s0Xgff1NsL0
- rtkwe 6y ago
  Tom Scott (who has a great channel btw) went through a simulator for it too. The complete reboot of people passing out is really interesting. For a funnier version (caused mostly be excitement rather than lack of blood) that doesn't involve people being moments from disaster check out the numerous Slingshot ride videos of people passing out. https://youtu.be/DMKcO-T5Y4o https://youtu.be/DMKcO-T5Y4o
stefan_ 6y ago
There is a video of what it sounds like: https://www.youtube.com/watch?v=WkZGL7RQBVw https://www.youtube.com/watch?v=WkZGL7RQBVw That automated recover voice is quite eerie.
- baybal2 6y ago
  I think it was his wing mate
  - stefan_ 6y ago
    I guess thats possible, but it seems quite.. regular?
    - throwanem 6y ago
      The repeated "Recover!" is indeed the formation leader, not an automated warning. It's as regular as it is because pilots, and especially military pilots, are trained to maintain a very strong radio discipline, and also (as Brian Shul notes in Sled Driver, his SR-71 memoir) because as a point of personal and cultural pride everyone wants to sound like Chuck Yeager on the radio. It makes sense, too; things can go wrong very fast in an airplane, and it does no one any good for a pilot to lose their cool in an emergency. Listen closely, and you'll notice that the formation leader lets that discipline fray a bit in the second and following calls, when some urgency bleeds through. This is because he suspects his trainee is about to die, which is what would indeed have happened if AGCAS hadn't been available. (You can also tell it's a radio call and not an annunciator by the form of address - the full call is "Two, recover!"; "Two" is what someone else in the formation calls its second member. "One" is the formation leader; in a four-ship formation you'd also have "Three" and "Four", and so on for larger groups.) edit: corrected some terminology
      - nanis 6y ago
        > Listen closely, and you'll notice that the element leader lets that discipline fray a bit Actually, the moment I heard him, I thought there was terror/panic in his voice which is warranted because > because he suspects his trainee is about to die came very close. Went from over 16,000 ft to under 5,000 ft. One thing I did not think was "this is a machine talking".
numlock86 6y ago
The article makes it sound like all Block 40 and newer F-16 have AGCAS. While this might be correct, it's worth mentioning that AGCAS was implemented around 2014 and started rolling out on F-16 after. Block 40/50 F-16s are way way way older than 2014 ... plus most non-US F-16 units didn't and won't get the update at all.
- cgearhart 6y ago
  Similar story for the F/A-18, but even later. The technology exists—Boeing even did a demonstration in the early/mid 2010’s. Navy only finally approved installing it in FY2019 budget, so it may not even be fielded yet. I used to work with a Marine F/A-18 pilot who came to the program office with an axe to grind about this. He requested meetings with PMA-265 (not our office, but same building—this was a very weird thing to do) to _politely_ show them the USAF F-16 AGCAS video and a list of folks he personally knew who died because we didn’t have AGCAS in F/A-18. I just looked him up, and he’s been promoted to Lt.CoL.; now working as the air systems lead for legacy F/A-18 in PMA-265–and it sounds like even legacy hornet is going to get AGCAS. I’m impressed (but perhaps not surprised) that he’s been able to get them to invest AGCAS in a platform that hits end-of-life in 2030. 11/10 would work with SOCK again.
jonplackett 6y ago
I wonder how close they actually got to the ground. It says it engaged at a few thousand feet but at fighter plane speed that could have been seconds until hitting the ground.
- rkangel 6y ago
  That was the most interesting bit to me. I am learning to fly an autogyro - 2000 to 3000 ft is our normal cruising altitude and I haven't been above 5000. The idea that you need to pull up at 4000 to not hit the ground says a lot about the speed.
  - implements 6y ago
    > I am learning to fly an autogyro ... Just to say, HNs had a comment yesterday with a terrifying video illustrating ‘the one big safety problem’ with autogyros - rotor disk unloading followed by “bunt over” (I think). I hope you don’t mind me saying ... please don’t skip any safety training, particularly if you come from conventional aircraft.
    - rkangel 6y ago
      I'm learning in the UK where you aren't permitted to skip anything. Even if you had a PPL for fixed wing (which I don't) it's only worth 15 hours of the required 45 in the gyro. I'd be curious to see the video, but modern gyros are less susceptible to it and it's simple to avoid as a pilot (far easier than stalls and spins). I find it alarming the degree to which US pilots can fly gyros with minimal specific training - they're very different to planes.
      - implements 6y ago
        Here it is: “Gyrocopter low g power push over crash” https://www.youtube.com/watch?v=CfjBzrSDrV0 https://www.youtube.com/watch?v=CfjBzrSDrV0 Warning: From the description: “This is a pretty sobering piece of film and its pretty obvious the pilot didn’t walk away. So if this is likely to upset you please don’t watch.”
Tade0 6y ago
Huh, nice to see something that I imagined would be introduced eventually, but didn't expect to arrive so soon. A while ago I came up with an idea for a short sci-fi story and it goes something like this: An AI assisted fighter jet is being developed which not only recovers from situations like in the article, but also performs some of the fight-related duties - often faster and better than a human pilot would - learning as it goes. The top brass is impressed, so the fighters are eventually sent on their first mission. Enemies are engaged and dispatched one by one, but two things seem off: the planes start making increasingly sharp(and effective) turns and contact with the crew becomes limited at first and stops altogether later on. As the last enemies start falling back the unit begins pursuit - even though they were ordered to return to base. No response. Meanwhile the aircrafts' movements become even more erratic - to the point where eventually they fall apart one by one from the sheer strees put on the parts. Recovered blackbox recordings indicate that by the time the enemies started retreating the pilots were all either unconscious or long dead.
- niea_11 6y ago
  This reminds me of an episode of Ghost in the shell (the serie, season 2 episode 4). from the description of the episode: the pilot of the helicopter suffers a massive heart attack, and the Jigabachi begins to spin out of control. The on-board Artificial Intelligence gets the helicopter back under control, and the military officers running the drill decide to abort it out of concern for the safety of their troops. However, the AI aboard the Jigabachi refuses to acknowledge the order to return to its parent JMSDF aircraft carrier. Acting on the assumption that the chopper is under attack, the AI overrides the flight controls of other armed Jigabachi aircraft, an air tanker from the carrier, and several nearby military bases, ordering these units into a tight defence formation in the heart of the Niihama Refugee Residential District. https://en.wikipedia.org/wiki/List_of_Ghost_in_the_Shell:_Stand_Alone_Complex_episodes#S.A.C._2nd_GIG https://en.wikipedia.org/wiki/List_of_Ghost_in_the_Shell:_St...
  - Tade0 6y ago
    Thanks for the pointer - I've only seen the movie and actually had no idea that a series existed.
alvah 6y ago
The plural of "aircraft" is not "aircrafts". Isn't English a requirement for sub-editors?
Toutouxc 6y ago
I wonder how many WW2 (the eastern front kind) and early-jet dogfights were won not because of airplane damage, but because one of the pilots GLOC'd himself and hit the ground.
- noneeeed 6y ago
  I've definitely heard stories from old pilots of blacking out and coming too while out of control, and then having to wrestle control back while coming round. I wouldn't be at all surprised if many more never recovered in time. I remember a WWI era flight-sim called Red Baron that included this in it's mechanics. If you tried to pull a turn too fast you'd start to black out and lose control.
  - jki275 6y ago
    Most flight sims model gloc, I remember it as far back as the 1980s Chuck Yeager series and it's definitely a thing in the F18 and F16 in DCS today.
- lakecresva 6y ago
  Or just exhaustion. There's an interview with a Japanese ace Honda Minoru on yt in which he talks about how pilots were so exhausted from flying eight hour combat missions every day of the Guadalcanal campaign that they would fall asleep at the controls, slowly fall out of formation, and hit the water. They (amazingly) had no radios in their aircraft at the time, so they just watched it happen.
  - fishnchips 6y ago
    IIRC they did have radios but those were so unreliable due to poor quality of vacuum tubes that many pilots chose not to use them, sometimes to the point of removing the antenna mast.
    - openasocket 6y ago
      The Japanese had a variety of issues with radios. Some Type 0 pilots did remove their radio system, to save weight, but only on land-based fighters. For carrier-based ships radios were still essential, because they used radio direction finding for navigation. Japanese carrier-based operations also suffered issues because they tended to use a single radio frequency for all air operations (meaning the channel could get disorganized). Japanese carriers also had their antennas on the sides of the ships rather than at the top of the island, which meant they often couldn't receive longer ranged transmissions, so it would be up to escorting cruisers to receive messages and then transmit them to the carrier. The book "Shattered Sword: The Untold Story of the Battle of Midway" has some good information about some of these nitty-gritty details.
Alex3917 6y ago
If you're going to park 600 military planes wingtip to wingtip, you might as well just program the software to purposely crash them all into the ground. Didn't we learn anything from Pearl Harbor?
blunte 6y ago
Watching videos of "normal" people riding as passengers in fighter jets, you often see them pass out briefly. The pilots are have the training and strategies to push their G limits much much higher, but even so it's still a risk. I wonder how long until we see a G-LOC accident in a modern fast accelerating electric car... I'm sure today's fastest accelerating street legal cars can do things to a body/brain that some people wouldn't be able to tolerate. (And also, if you consider how much ground you cover in the very brief 0-60 of a modern Tesla, it suggests that a poor choice with the right foot could lead to a very quick bad situation!)
- 70jS8h5L 6y ago
  Even the latest Tesla only reaches ~1.5G - not even that. G-LOC won't happen until 5 or 6, so I think we're a way off yet!
  - Symmetry 6y ago
    That's for young, fit, etc people. Some quick googling says a particularly susceptible person might very well pass out at as low as 3 Gs. Still way below what a Tesla can pull, though.
  - blunte 6y ago
    Considering how faint some passengers have looked with my boy-racing in the past, I suspect the G limit for some people is much much lower :).
    - offtop5 6y ago
      It wouldn't necessarily need to be g-forces, given how many Americans have severe underlying health issues, you might just go over a rough bump and have a stroke or something. Roller coasters tend to hit a good amount of gs, but if you pass out you'll be fine since you're not driving. One wonders if a Tesla detects its pilot unconscious can it bring itself to a full emergency stop. Automatically contact emts and then automatically distribute snacks to the arriving EMTs
- 6y ago
mikece 6y ago
1. I'm curious what happened to the pilots: did they remain in their role as fighter pilots or were they transferred to other airframes that pull fewer Gs? 2. I can't help but think about the possibility that software that can take over when it thinks the pilot is non-responsive could be hacked to crash on purpose or be taken over remotely. Perhaps this is a "feature" that will allow the F-16 fleet to be used as UCAVs without telling the public (or our enemies) about it?
- zucker42 6y ago
  I don't understand your second point. How could a F-16 be hacked remotely when there's no remote access? There's no attack surface. How is this different from any other fly-by-wire system?
  - greedo 6y ago
    There is remote access. Fighters routinely exchange data via datalink like LINK 16 and JTIDs. It's not inconceivable that this could lead to some exposure. It would depend on how segmented the flight control computers are from the other computers. A lot of the cyber warfare plans are attempting this type of attack.
    - jki275 6y ago
      Link-16 is JTIDS. It doesn't have any connection to flight controls or any controls of anything it's deployed in (which is just about everything). It's also type-1 encrypted.
      - greedo 6y ago
        So it sits on a separate bus, physically disconnected from any other flight computers?
        jki275 6y ago
        JTIDS is a radio. Flight controls don't get connected to radios. Except in the QF-16 perhaps.
ed25519FUUU 6y ago
> That suit dynamically responds to what the jet is doing, and squeezes the pilot’s lower body, like a high-tech blood-pressure cuff. I’m generally bearish on the supposed incoming AI dark winter, but aircraft navigation and dogfighting seem like they’re going to be much better suited flown by a computer. They can design aircraft that are much smaller and lighter, and can maneuver in ways that would cause a human to black out instantly.
- bluGill 6y ago
  You can fly a drone from your nice safe office which doesn't need to be anywhere near the war. No need for AI, though that is already used for the easy parts. For exactly the reasons you state.
sep_field 6y ago
who gives a fuck about two military murder-men. the world would have been better off if they had crashed and burned. fuck the capitalist imperialist slave-state. death to all military.
Animats 6y ago
Auto-GCAS is over 20 years old now. Here's a more technical description.[1] [1] https://www.f-16.net/f-16_versions_article8.html https://www.f-16.net/f-16_versions_article8.html
sandworm101 6y ago
Software is the implementation, but this is a large an nuanced program. I find the most interesting aspect is that this is software specifically ignores the pilot. If the g-locked/unconscious pilot is slumped over the controls the computer will ignore his stick inputs and substitute its own best judgment of the situation. (Pilot's stick says down, computer decides to ignore and pull up instead.) That is a really powerful change in pilot culture. It conflicts with the 737-Max fiasco where we all screamed that pilots should have final authority over computers. Getting this into f-16 cockpits must have involved many very heated discussions.
- FartyMcFarter 6y ago
  I'm not an expert, but I think F-16s were designed as fly-by-wire from the start, while 737s had mechanically-linked controls. This probably made it an easier sell on the F-16 case.
  - ckozlowski 6y ago
    Indeed. And another thing to consider is that some modern 4th gen performance aircraft require that fly-by-wire by design, as they're designed with inherent aerodynamic instability. You'd rapidly lose control of the plane if there was a FLCS (FLight Control System) failure. Checking status of these is part of the startup sequence. These systems are often triple or quadruple redundant, and will prevent the pilot from executing some maneuvers if it would put too much load on the aircraft. This can be relaxed for say, wartime situations, as placing high-Gs on the air frame reduces it's lifespan.
    - MaxBarraclough 6y ago
      > some modern 4th gen performance aircraft require that fly-by-wire by design, as they're designed with inherent aerodynamic instability The F-16 itself does exactly this. https://en.wikipedia.org/wiki/General_Dynamics_F-16_Fighting_Falcon#Negative_stability_and_fly-by-wire https://en.wikipedia.org/wiki/General_Dynamics_F-16_Fighting...
- 6y ago
Ancalagon 6y ago
Question: What repercussions does a pilot face after an incident like this? Is there more physical training done do the breathing maneuvers, and plane training to prevent excess G’s like this? Is the pilot grounded for a certain period of time?
amilein7minutes 6y ago
I might be the only one, but reading the article and the discussion here, I can't help but ask a bigger picture question on whether it is worth putting so many pilots through the torture of flying F-16's and F-35's. G-locking sounds extremely unpleasant. Does it have any longer term effects on the pilot? Despite the development on the software, aircraft technology, and the fundamental aerodynamics side that the F-35 and F-16 programs have brought about, they still seem inhuman to the aviators. Why isn't anyone questioning whether these high-maneuverability fighter aircraft should be used at all, especially given the huge budget of these programs?
- bradj 6y ago
  How would they plan to fight against other high maneuverability aircraft without comparable or better aircraft? There is definitely a goal of going unmanned at some point in the future in order to save lives, but the job still needs to be done today.
myrandomcomment 6y ago
So as an aside to this if you are a skydiver there is a thing called an ADD. https://en.wikipedia.org/wiki/Automatic_activation_device https://en.wikipedia.org/wiki/Automatic_activation_device In my 20 years of jumping I know 2 people that is saved. They hit the ground hard, but not terminally.
- Doxin 6y ago
  And for those curious to see what an ADD activation is like, there's a video of a couple skydivers forgetting to pull their chute[0]. Those guys definitely got their lifes saved by it. [0] https://www.youtube.com/watch?v=wCrvQ_xy_LA https://www.youtube.com/watch?v=wCrvQ_xy_LA
noctilux 6y ago
Finally, an uplifting story about software.

214 points by prostoalex 6y ago

I would guess that the presence of AGCAS is, in part, why the pilots were willing/allowed to push themselves so hard in training. I didn’t really say if the system only intervenes if it believes the pilot is unconscious or if it always intervenes if the fligh path is within some envelope of terraforming.

saberdancer 6y ago
I doubt they changed their training methods due to AGCAS. From my understanding, system works automatically and does not take into account whether pilot is conscious or not. It is not meant just to save unconscious pilots but also those who are disoriented (in fog, confused, ...). Given that it is a military aircraft, it's likely the system can be turned off if deemed necessary, for example if you are avoiding a missile it might be less risky to dive close to the ground than to pull up.
- Kolokius 6y ago
  I would guess there are two possibilities. The system won't override pilot input or the system only kicks in when it's 100% certain that a crash is inevitable. > If the system predicts an imminent collision, an autonomous avoidance maneuver—a roll to wings-level and +5g pull—is commanded at the last instance to prevent ground impact.” Sounds like by the time the system kicks in, you probably need it to kick in.
  - darkerside 6y ago
    Engineering doesn't typically work this way. There needs to be a tolerance because you can't account for all variables. The question really is, at what probability of likelihood of a crash do you want to attempt to avert it? Averting 99.5%+ of crashes probably eliminates flexibility beyond what is appropriate for a fighter pilot.
    - Kolokius 6y ago
      > “Auto-GCAS continuously compares a prediction of the aircraft’s trajectory against a terrain profile generated from onboard terrain elevation data. If the predicted trajectory touches the terrain profile, the automatic recovery is executed by the Auto GCAS autopilot. The automatic recovery maneuver consists of an abrupt roll-to-upright and a nominal 5-G pull until terrain clearance is assured.” https://sofrep.com/fightersweep/in-the-seat-with-agcas-those-lost-and-those-saved/ https://sofrep.com/fightersweep/in-the-seat-with-agcas-those... It predicts a trajectory. Either that trajectory looks like it'll hit the ground or not. If it doesn't, then there's no need to intervene.
      - aflag 6y ago
        Any nose dive will look like it will hit the ground, won't it? The question is at which attitude does it need to pull up. Obviously, there are many factors involved, but there may be other factors the system is not aware of, that's why it probably makes sense that's overridable. I bet there is a way to do it.
        jsmith45 6y ago
        It is mostly likely timing based. It may well calculate how much time is left until collision, or perhaps until a 5G pull will become insufficient to recover. When that time remaining drops below N seconds (which from looks to be perhaps 1-3 seconds if it is the until insufficient time metric, or perhaps an extra few seconds for time until collision) it will activate. Obviously there are other criteria to prevent a landing approach from being seen as an imminent crash etc. But an override system that cannot be accidentally held by a disoriented or unconscious pilot seems plausible.
  - jcims 6y ago
    There’s a short article here with a little more detail, sounds like it overrides pilot input as well (i.e. ‘nuisance flyups’) https://sofrep.com/fightersweep/in-the-seat-with-agcas-those-lost-and-those-saved/ https://sofrep.com/fightersweep/in-the-seat-with-agcas-those...
  - dTal 6y ago
    By the time it's 100% certain, there's nothing it can do. Any control input the system can make, the pilot could also be theoretically planning to make.
    - Kolokius 6y ago
      I didn't say "it's 100% certain that no matter what, there'll be a crash". Implied is that "100% certain of an impending crash without any extra input".
    - jki275 6y ago
      AGCAS was developed because pilots in the F16 specifically were blacking out from excess G forces and flying into terrain. An unconscious pilot isn't likely to make any useful control input at all.
      - jcims 6y ago
        Watching people convulse as they recover from GLOC in simulators makes me think that pilot input is probably best ignored.
rcxdude 6y ago
I doubt this is the case: the system was developed in part because blackouts were one of the leading causes of deaths during training.

hoseja 6y ago

"the system consists of a set of complex collision avoidance and autonomous decision making algorithms..." It's 50 nested ifs, isn't it.

mhh__ 6y ago
Actually - I sort of want to work in defense for a few years to find out, that and the sheer amount of tech in a modern missile (the fact that they would likely be used is why I didn't apply) - I reckon most the algorithms here are basically finely tuned signal processing and other non-"AI" processes. There's a tendency to think that everything that isn't completely ab initio like machine learning is bad or inelegant - I often fall for this trap myself, but to just get the job done you can get a very long way with "dumb" algorithms and a practically infinite budget.
- pjc50 6y ago
  The advantage of the "old" control systems approach is that it's not a black box; you can reason about its behavior across the state space and make assertions about its frequency response and stability conditions. (Is a neural network really different from a very large cascade of nonlinear filter elements?)
  - BrianOnHN 6y ago
    > Is a neural network really different from a very large cascade of nonlinear filter elements? It's different in theory, but not by much practically. Reverse engineering the former is a fool's errand, but so would be a sufficiently complex version of the latter. In terms of Kahneman's "Thinking Fast and Slow," ML, at least in its current stage, is like the fast thinking system. It's essential but is exponentially more valuable when combined with the slow system, which is still elusive in AI practice.
  - mhh__ 6y ago
    Indeed. I'm just kind of fascinated by military technology e.g. The F/A-18's cockpit HMDs and Hud were light-years ahead of anything in star wars with the exception of holograms even in 1983.

mothsonasloth 6y ago

Just reminded me of this video of G-LOC https://youtu.be/s0Xgff1NsL0 https://youtu.be/s0Xgff1NsL0

rtkwe 6y ago
Tom Scott (who has a great channel btw) went through a simulator for it too. The complete reboot of people passing out is really interesting. For a funnier version (caused mostly be excitement rather than lack of blood) that doesn't involve people being moments from disaster check out the numerous Slingshot ride videos of people passing out. https://youtu.be/DMKcO-T5Y4o https://youtu.be/DMKcO-T5Y4o

stefan_ 6y ago

There is a video of what it sounds like: https://www.youtube.com/watch?v=WkZGL7RQBVw https://www.youtube.com/watch?v=WkZGL7RQBVw That automated recover voice is quite eerie.

baybal2 6y ago
I think it was his wing mate
- stefan_ 6y ago
  I guess thats possible, but it seems quite.. regular?
  - throwanem 6y ago
    The repeated "Recover!" is indeed the formation leader, not an automated warning. It's as regular as it is because pilots, and especially military pilots, are trained to maintain a very strong radio discipline, and also (as Brian Shul notes in Sled Driver, his SR-71 memoir) because as a point of personal and cultural pride everyone wants to sound like Chuck Yeager on the radio. It makes sense, too; things can go wrong very fast in an airplane, and it does no one any good for a pilot to lose their cool in an emergency. Listen closely, and you'll notice that the formation leader lets that discipline fray a bit in the second and following calls, when some urgency bleeds through. This is because he suspects his trainee is about to die, which is what would indeed have happened if AGCAS hadn't been available. (You can also tell it's a radio call and not an annunciator by the form of address - the full call is "Two, recover!"; "Two" is what someone else in the formation calls its second member. "One" is the formation leader; in a four-ship formation you'd also have "Three" and "Four", and so on for larger groups.) edit: corrected some terminology
    - nanis 6y ago
      > Listen closely, and you'll notice that the element leader lets that discipline fray a bit Actually, the moment I heard him, I thought there was terror/panic in his voice which is warranted because > because he suspects his trainee is about to die came very close. Went from over 16,000 ft to under 5,000 ft. One thing I did not think was "this is a machine talking".

numlock86 6y ago

The article makes it sound like all Block 40 and newer F-16 have AGCAS. While this might be correct, it's worth mentioning that AGCAS was implemented around 2014 and started rolling out on F-16 after. Block 40/50 F-16s are way way way older than 2014 ... plus most non-US F-16 units didn't and won't get the update at all.

cgearhart 6y ago
Similar story for the F/A-18, but even later. The technology exists—Boeing even did a demonstration in the early/mid 2010’s. Navy only finally approved installing it in FY2019 budget, so it may not even be fielded yet. I used to work with a Marine F/A-18 pilot who came to the program office with an axe to grind about this. He requested meetings with PMA-265 (not our office, but same building—this was a very weird thing to do) to _politely_ show them the USAF F-16 AGCAS video and a list of folks he personally knew who died because we didn’t have AGCAS in F/A-18. I just looked him up, and he’s been promoted to Lt.CoL.; now working as the air systems lead for legacy F/A-18 in PMA-265–and it sounds like even legacy hornet is going to get AGCAS. I’m impressed (but perhaps not surprised) that he’s been able to get them to invest AGCAS in a platform that hits end-of-life in 2030. 11/10 would work with SOCK again.

jonplackett 6y ago

I wonder how close they actually got to the ground. It says it engaged at a few thousand feet but at fighter plane speed that could have been seconds until hitting the ground.

rkangel 6y ago
That was the most interesting bit to me. I am learning to fly an autogyro - 2000 to 3000 ft is our normal cruising altitude and I haven't been above 5000. The idea that you need to pull up at 4000 to not hit the ground says a lot about the speed.
- implements 6y ago
  > I am learning to fly an autogyro ... Just to say, HNs had a comment yesterday with a terrifying video illustrating ‘the one big safety problem’ with autogyros - rotor disk unloading followed by “bunt over” (I think). I hope you don’t mind me saying ... please don’t skip any safety training, particularly if you come from conventional aircraft.
  - rkangel 6y ago
    I'm learning in the UK where you aren't permitted to skip anything. Even if you had a PPL for fixed wing (which I don't) it's only worth 15 hours of the required 45 in the gyro. I'd be curious to see the video, but modern gyros are less susceptible to it and it's simple to avoid as a pilot (far easier than stalls and spins). I find it alarming the degree to which US pilots can fly gyros with minimal specific training - they're very different to planes.
    - implements 6y ago
      Here it is: “Gyrocopter low g power push over crash” https://www.youtube.com/watch?v=CfjBzrSDrV0 https://www.youtube.com/watch?v=CfjBzrSDrV0 Warning: From the description: “This is a pretty sobering piece of film and its pretty obvious the pilot didn’t walk away. So if this is likely to upset you please don’t watch.”

Tade0 6y ago

Huh, nice to see something that I imagined would be introduced eventually, but didn't expect to arrive so soon. A while ago I came up with an idea for a short sci-fi story and it goes something like this: An AI assisted fighter jet is being developed which not only recovers from situations like in the article, but also performs some of the fight-related duties - often faster and better than a human pilot would - learning as it goes. The top brass is impressed, so the fighters are eventually sent on their first mission. Enemies are engaged and dispatched one by one, but two things seem off: the planes start making increasingly sharp(and effective) turns and contact with the crew becomes limited at first and stops altogether later on. As the last enemies start falling back the unit begins pursuit - even though they were ordered to return to base. No response. Meanwhile the aircrafts' movements become even more erratic - to the point where eventually they fall apart one by one from the sheer strees put on the parts. Recovered blackbox recordings indicate that by the time the enemies started retreating the pilots were all either unconscious or long dead.

niea_11 6y ago
This reminds me of an episode of Ghost in the shell (the serie, season 2 episode 4). from the description of the episode: the pilot of the helicopter suffers a massive heart attack, and the Jigabachi begins to spin out of control. The on-board Artificial Intelligence gets the helicopter back under control, and the military officers running the drill decide to abort it out of concern for the safety of their troops. However, the AI aboard the Jigabachi refuses to acknowledge the order to return to its parent JMSDF aircraft carrier. Acting on the assumption that the chopper is under attack, the AI overrides the flight controls of other armed Jigabachi aircraft, an air tanker from the carrier, and several nearby military bases, ordering these units into a tight defence formation in the heart of the Niihama Refugee Residential District. https://en.wikipedia.org/wiki/List_of_Ghost_in_the_Shell:_Stand_Alone_Complex_episodes#S.A.C._2nd_GIG https://en.wikipedia.org/wiki/List_of_Ghost_in_the_Shell:_St...
- Tade0 6y ago
  Thanks for the pointer - I've only seen the movie and actually had no idea that a series existed.

alvah 6y ago

The plural of "aircraft" is not "aircrafts". Isn't English a requirement for sub-editors?

Toutouxc 6y ago

I wonder how many WW2 (the eastern front kind) and early-jet dogfights were won not because of airplane damage, but because one of the pilots GLOC'd himself and hit the ground.

noneeeed 6y ago
I've definitely heard stories from old pilots of blacking out and coming too while out of control, and then having to wrestle control back while coming round. I wouldn't be at all surprised if many more never recovered in time. I remember a WWI era flight-sim called Red Baron that included this in it's mechanics. If you tried to pull a turn too fast you'd start to black out and lose control.
- jki275 6y ago
  Most flight sims model gloc, I remember it as far back as the 1980s Chuck Yeager series and it's definitely a thing in the F18 and F16 in DCS today.
lakecresva 6y ago
Or just exhaustion. There's an interview with a Japanese ace Honda Minoru on yt in which he talks about how pilots were so exhausted from flying eight hour combat missions every day of the Guadalcanal campaign that they would fall asleep at the controls, slowly fall out of formation, and hit the water. They (amazingly) had no radios in their aircraft at the time, so they just watched it happen.
- fishnchips 6y ago
  IIRC they did have radios but those were so unreliable due to poor quality of vacuum tubes that many pilots chose not to use them, sometimes to the point of removing the antenna mast.
  - openasocket 6y ago
    The Japanese had a variety of issues with radios. Some Type 0 pilots did remove their radio system, to save weight, but only on land-based fighters. For carrier-based ships radios were still essential, because they used radio direction finding for navigation. Japanese carrier-based operations also suffered issues because they tended to use a single radio frequency for all air operations (meaning the channel could get disorganized). Japanese carriers also had their antennas on the sides of the ships rather than at the top of the island, which meant they often couldn't receive longer ranged transmissions, so it would be up to escorting cruisers to receive messages and then transmit them to the carrier. The book "Shattered Sword: The Untold Story of the Battle of Midway" has some good information about some of these nitty-gritty details.

Alex3917 6y ago

If you're going to park 600 military planes wingtip to wingtip, you might as well just program the software to purposely crash them all into the ground. Didn't we learn anything from Pearl Harbor?

blunte 6y ago

Watching videos of "normal" people riding as passengers in fighter jets, you often see them pass out briefly. The pilots are have the training and strategies to push their G limits much much higher, but even so it's still a risk. I wonder how long until we see a G-LOC accident in a modern fast accelerating electric car... I'm sure today's fastest accelerating street legal cars can do things to a body/brain that some people wouldn't be able to tolerate. (And also, if you consider how much ground you cover in the very brief 0-60 of a modern Tesla, it suggests that a poor choice with the right foot could lead to a very quick bad situation!)

70jS8h5L 6y ago
Even the latest Tesla only reaches ~1.5G - not even that. G-LOC won't happen until 5 or 6, so I think we're a way off yet!
- Symmetry 6y ago
  That's for young, fit, etc people. Some quick googling says a particularly susceptible person might very well pass out at as low as 3 Gs. Still way below what a Tesla can pull, though.
- blunte 6y ago
  Considering how faint some passengers have looked with my boy-racing in the past, I suspect the G limit for some people is much much lower :).
  - offtop5 6y ago
    It wouldn't necessarily need to be g-forces, given how many Americans have severe underlying health issues, you might just go over a rough bump and have a stroke or something. Roller coasters tend to hit a good amount of gs, but if you pass out you'll be fine since you're not driving. One wonders if a Tesla detects its pilot unconscious can it bring itself to a full emergency stop. Automatically contact emts and then automatically distribute snacks to the arriving EMTs
6y ago

mikece 6y ago

1. I'm curious what happened to the pilots: did they remain in their role as fighter pilots or were they transferred to other airframes that pull fewer Gs? 2. I can't help but think about the possibility that software that can take over when it thinks the pilot is non-responsive could be hacked to crash on purpose or be taken over remotely. Perhaps this is a "feature" that will allow the F-16 fleet to be used as UCAVs without telling the public (or our enemies) about it?

zucker42 6y ago
I don't understand your second point. How could a F-16 be hacked remotely when there's no remote access? There's no attack surface. How is this different from any other fly-by-wire system?
- greedo 6y ago
  There is remote access. Fighters routinely exchange data via datalink like LINK 16 and JTIDs. It's not inconceivable that this could lead to some exposure. It would depend on how segmented the flight control computers are from the other computers. A lot of the cyber warfare plans are attempting this type of attack.
  - jki275 6y ago
    Link-16 is JTIDS. It doesn't have any connection to flight controls or any controls of anything it's deployed in (which is just about everything). It's also type-1 encrypted.
    - greedo 6y ago
      So it sits on a separate bus, physically disconnected from any other flight computers?
      - jki275 6y ago
        JTIDS is a radio. Flight controls don't get connected to radios. Except in the QF-16 perhaps.

ed25519FUUU 6y ago

> That suit dynamically responds to what the jet is doing, and squeezes the pilot’s lower body, like a high-tech blood-pressure cuff. I’m generally bearish on the supposed incoming AI dark winter, but aircraft navigation and dogfighting seem like they’re going to be much better suited flown by a computer. They can design aircraft that are much smaller and lighter, and can maneuver in ways that would cause a human to black out instantly.

bluGill 6y ago
You can fly a drone from your nice safe office which doesn't need to be anywhere near the war. No need for AI, though that is already used for the easy parts. For exactly the reasons you state.

sep_field 6y ago

who gives a fuck about two military murder-men. the world would have been better off if they had crashed and burned. fuck the capitalist imperialist slave-state. death to all military.

Animats 6y ago

Auto-GCAS is over 20 years old now. Here's a more technical description.[1] [1] https://www.f-16.net/f-16_versions_article8.html https://www.f-16.net/f-16_versions_article8.html

sandworm101 6y ago

Software is the implementation, but this is a large an nuanced program. I find the most interesting aspect is that this is software specifically ignores the pilot. If the g-locked/unconscious pilot is slumped over the controls the computer will ignore his stick inputs and substitute its own best judgment of the situation. (Pilot's stick says down, computer decides to ignore and pull up instead.) That is a really powerful change in pilot culture. It conflicts with the 737-Max fiasco where we all screamed that pilots should have final authority over computers. Getting this into f-16 cockpits must have involved many very heated discussions.

FartyMcFarter 6y ago
I'm not an expert, but I think F-16s were designed as fly-by-wire from the start, while 737s had mechanically-linked controls. This probably made it an easier sell on the F-16 case.
- ckozlowski 6y ago
  Indeed. And another thing to consider is that some modern 4th gen performance aircraft require that fly-by-wire by design, as they're designed with inherent aerodynamic instability. You'd rapidly lose control of the plane if there was a FLCS (FLight Control System) failure. Checking status of these is part of the startup sequence. These systems are often triple or quadruple redundant, and will prevent the pilot from executing some maneuvers if it would put too much load on the aircraft. This can be relaxed for say, wartime situations, as placing high-Gs on the air frame reduces it's lifespan.
  - MaxBarraclough 6y ago
    > some modern 4th gen performance aircraft require that fly-by-wire by design, as they're designed with inherent aerodynamic instability The F-16 itself does exactly this. https://en.wikipedia.org/wiki/General_Dynamics_F-16_Fighting_Falcon#Negative_stability_and_fly-by-wire https://en.wikipedia.org/wiki/General_Dynamics_F-16_Fighting...
6y ago

Ancalagon 6y ago

Question: What repercussions does a pilot face after an incident like this? Is there more physical training done do the breathing maneuvers, and plane training to prevent excess G’s like this? Is the pilot grounded for a certain period of time?

amilein7minutes 6y ago

I might be the only one, but reading the article and the discussion here, I can't help but ask a bigger picture question on whether it is worth putting so many pilots through the torture of flying F-16's and F-35's. G-locking sounds extremely unpleasant. Does it have any longer term effects on the pilot? Despite the development on the software, aircraft technology, and the fundamental aerodynamics side that the F-35 and F-16 programs have brought about, they still seem inhuman to the aviators. Why isn't anyone questioning whether these high-maneuverability fighter aircraft should be used at all, especially given the huge budget of these programs?

bradj 6y ago
How would they plan to fight against other high maneuverability aircraft without comparable or better aircraft? There is definitely a goal of going unmanned at some point in the future in order to save lives, but the job still needs to be done today.

myrandomcomment 6y ago

So as an aside to this if you are a skydiver there is a thing called an ADD. https://en.wikipedia.org/wiki/Automatic_activation_device https://en.wikipedia.org/wiki/Automatic_activation_device In my 20 years of jumping I know 2 people that is saved. They hit the ground hard, but not terminally.

Doxin 6y ago
And for those curious to see what an ADD activation is like, there's a video of a couple skydivers forgetting to pull their chute[0]. Those guys definitely got their lifes saved by it. [0] https://www.youtube.com/watch?v=wCrvQ_xy_LA https://www.youtube.com/watch?v=wCrvQ_xy_LA

noctilux 6y ago

Finally, an uplifting story about software.