Auto GCAS recovery

Velocity173

Velocity173

Touchdown! Greaser!
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Velocity173
Think he held the first "hook" too long. I would've blacked out again on the 9 G recovery! :D

 
Saw this earlier waiting for someone to post it. Very cool that it can do that, amazing how such velocity turns a big sky into something where 10k ft is minimal room to recover. Anybody whos pulled that kind of G does it "scale" steeply past 6 G's or so as far as physiological effects. My 1 acro flight years ago was only to six g's but sitting there in a 80degree bank it was very tolerable. Negative 3 on an outside loop made me wanna die though lol.
 
falconkidding said:
Saw this earlier waiting for someone to post it. Very cool that it can do that, amazing how such velocity turns a big sky into something where 10k ft is minimal room to recover. Anybody whos pulled that kind of G does it "scale" steeply past 6 G's or so as far as physiological effects. My 1 acro flight years ago was only to six g's but sitting there in a 80degree bank it was very tolerable. Negative 3 on an outside loop made me wanna die though lol.
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Yeah he lost 10K in a blink of an eye. 692 KIAS going down!

Saw a F-18 accident on the radar tapes years ago. Went from 8K to nothing in one sweep.:(
 
Detailed article at Aviation Week: http://aviationweek.com/technology/auto-gcas-saves-unconscious-f-16-pilot-declassified-usaf-footage

I was wondering how many widgets the system took to make work, and it seems it is a terrain map, and inputs of current performance data to determine if they will intersect. Though I wonder what the damping logic is as I assume fighters end up pointed at the ground under normal operations from time to time.

On the other hands, those look like 8 but graphics on the HUD. Ewww.
 
Oh, the student pulled the 9.1 G and not the computer. I was about to say, that thing recovers pretty darn aggressively!
 
masloki said:
I was wondering how many widgets the system took to make work, and it seems it is a terrain map, and inputs of current performance data to determine if they will intersect. Though I wonder what the damping logic is as I assume fighters end up pointed at the ground under normal operations from time to time.
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Enhanced DTU, a new Data Cart and TERPROM software were used on the original system. The system utilizes various other systems already on the aircraft. Here is a link to the latest system and it's integration on the F-16 and other aircraft: http://www.airforcemag.com/MagazineArchive/Documents/2016/February 2016/0216avoidance.pdf
A friend of mine just retired as the project lead on the ACAT program.
 
Velocity173 said:
Oh, the student pulled the 9.1 G and not the computer. I was about to say, that thing recovers pretty darn aggressively!
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I first saw the video and it had no explanation so I thought the GCAS pulled 9.1 as well. Since everything turned out okay for the student, I laughed at the thought of him blacking out to 8g.. recovering for a second to see the ground rushing up at him, and having the plane say "go back to sleep" and recovering at 9g.
 
Left side of the display, at the top and just right of the air speed ribbon, is the instantaneous G reading and at the bottom is the peak G.
 
Velocity173 said:
Oh, the student pulled the 9.1 G and not the computer. I was about to say, that thing recovers pretty darn aggressively!
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Sure looks like the pilot lost it in the first aggressive pull to 8.1 g peak then relaxed on the controls letting the aircraft enter a steep dive. Then the auto GCAS did indeed reach 9.1g in the pullout unless the other voice was an instructor who "helped" the computer. It's clear that the peak g was barely over 8 until the final recovery.
 
gismo said:
Sure looks like the pilot lost it in the first aggressive pull to 8.1 g peak then relaxed on the controls letting the aircraft enter a steep dive. Then the auto GCAS did indeed reach 9.1g in the pullout unless the other voice was an instructor who "helped" the computer. It's clear that the peak g was barely over 8 until the final recovery.
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Yeah he held the initial hook, then it seemed he tried to take in air for the second hook and it was lights out.

The auto GCAS only pulls to 5 g so when the student woke up, he must have pulled the rest.
 
Jokes about HUD displays aside, this cat is lucky to be alive. AGSM is serious business. I've lost students and peers alike in Viper/Eagle GLOC incidents. Everyone is a tough guy because they spiked 9 Gs in an acro plane once, but the reality of the matter is that the kind of multiple engagements in less than an hour's time take a toll on your G-tolerance, never mind double turning in the middle of a stressful B-course. Statistics also show that it isn't the 9Gs that get ya, it's much lower Gs with a rapid onset or even on the decrease, as a result of cumulative fatigue and lack of discipline during end-of-sortie engagements. I won't debrief the AGSM in question on this forum, but for those educated on the matter, the video is self-evident regarding how messed up the maneuver was even before he began the pull.

This is why I cannot wait for the T-X to get here. The Talon has done its job but we're way too G-restricted to properly acclimate follow-on students to the rigors of a grey jet that sustains Gs at a higher level than most young fighter pilots' resting tolerance (4-4.5Gs). Meaning, we can cheat-AGSM all day in UPT and just sound like we're doing it right....until it catches up to ya in the B-course.

I know my studs roll their eyes at me on the inside when I give them lip about a proper AGSM. I know they're cheating in the front, and there have been occasions where I myself haven't been the most disciplined about it, since I'm so acclimated to the 38 and it can't pull that much anyways, which is exactly how one gets in trouble. Videos like this one are indispensable into driving home the point that you have to respect the Gs and get into it with a defensive posture, especially after the second or so engagement, let alone a second or third sortie. And don't be afraid to back off and ratchet down.

The "problem" is that these young men are alpha of the alpha, they'll turn that jet like their wings are on the line (and they are). They didn't get fighters (TACAIR for the NAVY brethren) by backing off in life. Their level of commitment is unparalleled, having attained the jet of their dreams after such hard work and competition, much to the pride and jealousy of those of us who didn't hit the AF at the right time (TAMI-21 and bomber duty) who wish we were 10 years younger today.

If I can get my studs out to IFF with a high degree of respect for G management within the constraints of the tools assigned to me (T-38 and T-6 before that) I feel I've done my part in creating the best cadre of combat aviators the world's sky has trembled under. For everybody else, fly safe out there and always give yourself an out.
 
hindsight2020 said:
Jokes about HUD displays aside, this cat is lucky to be alive. AGSM is serious business. I've lost students and peers alike in Viper/Eagle GLOC incidents. Everyone is a tough guy because they spiked 9 Gs in an acro plane once, but the reality of the matter is that the kind of multiple engagements in less than an hour's time take a toll on your G-tolerance, never mind double turning in the middle of a stressful B-course. Statistics also show that it isn't the 9Gs that get ya, it's much lower Gs with a rapid onset or even on the decrease, as a result of cumulative fatigue and lack of discipline during end-of-sortie engagements. I won't debrief the AGSM in question on this forum, but for those educated on the matter, the video is self-evident regarding how messed up the maneuver was even before he began the pull.

This is why I cannot wait for the T-X to get here. The Talon has done its job but we're way too G-restricted to properly acclimate follow-on students to the rigors of a grey jet that sustains Gs at a higher level than most young fighter pilots' resting tolerance (4-4.5Gs). Meaning, we can cheat-AGSM all day in UPT and just sound like we're doing it right....until it catches up to ya in the B-course.

I know my studs roll their eyes at me on the inside when I give them lip about a proper AGSM. I know they're cheating in the front, and there have been occasions where I myself haven't been the most disciplined about it, since I'm so acclimated to the 38 and it can't pull that much anyways, which is exactly how one gets in trouble. Videos like this one are indispensable into driving home the point that you have to respect the Gs and get into it with a defensive posture, especially after the second or so engagement, let alone a second or third sortie. And don't be afraid to back off and ratchet down.

The "problem" is that these young men are alpha of the alpha, they'll turn that jet like their wings are on the line (and they are). They didn't get fighters (TACAIR for the NAVY brethren) by backing off in life. Their level of commitment is unparalleled, having attained the jet of their dreams after such hard work and competition, much to the pride and jealousy of those of us who didn't hit the AF at the right time (TAMI-21 and bomber duty) who wish we were 10 years younger today.

If I can get my studs out to IFF with a high degree of respect for G management within the constraints of the tools assigned to me (T-38 and T-6 before that) I feel I've done my part in creating the best cadre of combat aviators the world's sky has trembled under. For everybody else, fly safe out there and always give yourself an out.
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What could the student in the vid have done better as far as the AGSM?
 
Velocity173 said:
What could the student in the vid have done better as far as the AGSM?
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For starters, not take that insane inhale of air like he was gonna go for a world record of holding your breath. Counter-intuitive as it may be for the gallery, having a lot of air in your lungs will actually make it harder for your torso to keep air in the lungs under G. The second was probably sloppy G-strain. We don't know if this was the second sortie of the day or what the level of hydration of the student was, all which affect the G-tolerance on a day to day variance. I've lost color acuity on a third go sortie by virtue of dehydration alone, while the first go sortie was cake. It can be that sensitive.

The nail was committing to the pull at 6Gs after the first inhale under G. It was game over at that point. It takes a experience and humility to back off and K-I-O when the world starts going grey. But you don't get your dream fighter by backing off. So it's a razor wire we pointy nose folks dance on when it comes to this gig.

He got a do-over in life. Others haven't been as fortunate. A lesson for all of us indeed.
 
If this happened in a real life ACM situation, wouldn't the GLOC pilot be fatally undefensive when the airplane takes over to prevent a crash? Or is that when Maveric the wingman saves the day?
 
I think aside from teaching proper AGSM technique, the 'fuge more importantly in my mind shows a guy (or gal) what greyout looks and feels like in a safe environment, and also teaches some proper respect for rapid onset/hi-G maneuvers. Armed with that experience, you can go out and fight smartly. By that, I mean backing off a bit when you get ahead of your body and things start to grey……it isn't a red crash phone call a KIO and go home, just let your body catch up and then get back on it. You can do sustained 5-6G's with mostly just your legs and glutes straining as long as you have a smooth in and out breathing pattern. The hook or hick or whatever it is called now is great but a little excessive unless you are in the sustained 7-9G range, best example being a Viper on the 9G limiter and holding it there. However, caveat to all of that, rapid onset without the appropriate body prep, and you are off to the races, at least if you don't start easing within a couple three seconds.
 
Here is HUD video that shows much better control for sustained g loading.

This is the standard company airshow demo, and our pilots fly it twice a day, for up to two weeks in prep for a customer.
 
There is more pain to be had in a slick F-16 down low between 300 and 400 knots than just about anything else in the world. Above 400 knots, you better come out of AB, because you will be on the limiter and accelerating. It is a beast, and you learn quick to back off a little on an "off day". Flying a single seat 9G jet requires some respect for your own physical limitations on a day to day basis, at least if you want to remain alive.
 
hindsight2020 said:
If I can get my studs out to IFF with a high degree of respect for G management within the constraints of the tools assigned to me (T-38 and T-6 before that) I feel I've done my part in creating the best cadre of combat aviators the world's sky has trembled under. For everybody else, fly safe out there and always give yourself an out.
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A moment of inattention in the overhead in the back of a T-38 (before the g-limits became so onerous) taught me more about g-onset than hours of physiology lectures ever could. :confused:

Nauga,
who woke up on downwind
 
nauga said:
A moment of inattention in the overhead in the back of a T-38 (before the g-limits became so onerous) taught me more about g-onset than hours of physiology lectures ever could. :confused:

Nauga,
who woke up on downwind
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Yikes. That would not be a good feeling.
 
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