Ground Collision Avoidance System ‘Saves’ First F-16 in Syria

http://aviationweek.com/defense/ground-collision-avoidance-system-saves-first-f-16-syria

by aerocapture • 11 years ago

130 60 11 years ago

This is really interesting. I found a PDF with some neat details and imagery describing the thinking that goes into Auto GCAS:

http://www.sfte2013.com/files/78993619.pdf

I don't know if it's just coincidental, but a lot of the examples seem to be concerned with keeping jets from flying into mountains, as opposed to flying into level ground, which was the first thing that came into mind when I saw "Ground Collision."

mik3y• 11 years ago

Cool find! The pictures (and one slide) show an Android phone being used on a "Dryden drone", looks like it might have been a prototyping platform. Would love to see more detail about this.

Edit: Ah, here's a senior project at CalPoly that was sponsored by NASA and looks related: http://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?articl...

termain• 11 years ago

Quite impressive senior project. I know CalPoly aerospace does well with interacting with the industry and NASA.

gonzo• 11 years ago

I get "This site does not exist within the LDAP database." when I try that link. Mirror?

aerocapture• 11 years ago

Here's a recent video from NASA's Armstrong Flight Research Center discussing the Automatic Collision Avoidance Technology and the DROID UAV platform specifically.

https://www.youtube.com/watch?v=XWx6-aK8Ick

kator2• 11 years ago

I just finished the book "Skunk Works: A Personal Memoir of My Years of Lockheed"

http://www.amazon.com/Skunk-Works-Personal-Memoir-Lockheed-e...

It was a great book that almost feels like the pre-scrum manifesto applied to building aircraft.

nether• 11 years ago

All right, this has nothing to do with the Northrop/GD F-16.

kator2• 11 years ago

FTA: "Auto GCAS, which was developed by Lockheed Martin’s Skunk Works"

afterburner2• 11 years ago

"According to the Air Force, 26% of aircraft losses and 75% of all F-16 fatalities are caused by such accidents."

Wow.

marvin• 11 years ago

Keep in mind that jet fighter crashes are often survived by the pilot if he or she has the time to react and bail out. Many crashes are caused by technical malfunction or loss of control at altitudes where the pilot has plenty of time to react.

However, if the pilot is still on board, ground collision at flight speed is almost universally fatal. Fighter pilots during ground attack or low-level dogfighting are always pushing the envelope both in aerodynamic/structural capability and maneuvering wrt. terrain hazards, so ground collision is a very serious safety hazard. Military pilots have much, much smaller margins of error than commercial or recreational pilots.

afterburner2• 11 years ago

Yes, the wow was more about the 26%.

konstruktor• 11 years ago

The article specifically talks about controlled flight into terrain, which, by definition excludes malfunctions.

derwildemomo• 11 years ago

That's great.

Maybe someone here can enlighten me as to why the systems, specifically TCAS and GPWS in modern civilian planes are only ever used to issue warnings/recommendations, but never take control? it would have at least prevented the überlingen mid air collision and probably some other CFIR incidents in the past years.

I thought about this for a while and couldn't come up with a really good reason.

neurotech1• 11 years ago

Auto GCAS also used in cases of G-LOC (G-Induced Loss of Consciousness) which is practically unheard of in a civilian airliner that is able to land safely afterwards.

Fighter aircraft frequently engage in maneuvers that are seconds away from hitting the ground (or water) if something goes wrong.

überlingen was a tragic anomaly caused by multiple factors, the pilots knew they were on a collision course but due to the conflict between TCAS and ATC they collided. This possibility has been reduced by issuing a TCAS reversal if the other jet responds differently than expected.

tiwfm2• 11 years ago

Early TCAS versions did not even provide correctives, so systems that even provide RAs you could use for automatic corrections are relatively new. Give it (a lot of) time.

ridgeguy• 11 years ago

Might be product liability issues. Software malf may have completely different economic consequences in civilian vs. military environments.

Perdition2• 11 years ago

Difficulty of international agreements, and the expense.

Upgrading to fully autonomous systems adds a lot of cost but is only going to make a difference in a small number of incidents (civilian aircraft don't fly as low and fast as fighters, and civilian pilots aren't distracted by being shot at).

hudibras• 11 years ago

It's only a matter of time. My guess is that it'll happen within the next 30 years.

WalterBright• 11 years ago

Reminds me of a description of air combat where the pursued would dive, and then pull out at the last possible moment, hoping the pursuer would misjudge and pull out too late. One pulled out so low he raised dust on the ground.

My father liked to attack ack-ack positions by diving vertically on them, as the gun crew obviously was reluctant to fire straight up. Of course, you gotta keep a real close eye on your altitude and airspeed doing that.

thecopy• 11 years ago

There was an incident (among many) between a Swedish figher and the Russian figher on Swedish territory maybe 20 years ago where the Russian was following the Swedish fighter. The Swedish planes being more sophisticated then the Russian fighters, the Swedish pilot went for the sea, straight bown. He pulled back when he knew his plane would make it, but the Russian figher jet could not handle the G's, broke and crashed into the sea killing the pilot.

trhway• 11 years ago

misjudge and pull out too late

Su-30 at airshow:

https://www.youtube.com/watch?v=YcUvtnL5p4Y

ForHackernews• 11 years ago

"a 5g pull"

Yikes!

Sharlin• 11 years ago

That's a pretty run-of-the-mill acceleration as far as fighter maneuvers go. Momentary accelerations in excess of 10g are not unheard of and the use of an ejection seat exposes the pilot to 12g or even more.

Perdition2• 11 years ago

Yeah but ejecting is often career ending because of those G's.

throwaway8898• 11 years ago

hmm ... as a pilot and student of WW2 combat, I think this might be ok in peace-time, but definitely a problem in war time.

- to avoid radar, you have to fly low - tree-top high - to save ammo, you have to shoot near ground-targets - can the software be fooled in mountainous terrain? - what about off-field landings? - Japan's most effective bombers were kamikaze, and American pilots also considered ramming other aircraft after their ammo ran out - if the software is wrong, does it roll inverted and pull down at 5G? how do you stop it?

sharth• 11 years ago

The article says that 1. The pilot is first notified that the system is about to take control. and 2. That the pilot can override the system at any time.

jjwiseman• 11 years ago

From http://www.aerotechnews.com/laafb/files/publications/ala_100..., it looks like it's designed to avoid "nuisance activations": “As Nils got down low, I could see dirt being kicked up off of the desert floor and no nuisance activations.”

mjmahone17• 11 years ago

1,600 automatic avoidances in 141 hours of flight. Holy crap, that's a lot of "point it at the ground, hope you don't die". Unless they did something else?

kelseyfrancis• 11 years ago

Did you RTFA? Do you honestly believe these utterly basic questions you've posed after a few seconds of consideration never occurred to any Air Force or Lockheed or NASA personnel involved in building this system? Or are you just cynical enough to believe the Air Force isn't really concerned about the "war time" effectiveness of its _fighter_ planes?

dankohn1• 11 years ago

Can you imagine the testing rigor you would need for this sort of system, knowing that if you incorrectly engaged or steered the aircraft, you would be responsible for killing the pilot?

ccleve• 11 years ago

My thought exactly. Warning! Warning! NullPointerException!

No, that's a contract I do not want.

iLoch• 11 years ago

I remember reading somewhere that these guys get all the time they want to program these systems, and the environment is very relaxed - I suppose for this very reason.

thrownaway2424• 11 years ago

The meatware are already notorious for driving the aircraft into the ground. How much worse could the software people make it? Anyway they've had twenty years to work on this system according to the article.

Htsthbjig• 11 years ago

We have programmed such systems.

We have programs to test all the possibilities in the software.

And we have programs to test the testing programs.

All hardware has redundancy. The software is executed in multiple processors at the same time, so if one fails, the others take control.

DrStalker• 11 years ago

I've heard (no source sorry) that in early testing in a simulator flying an F-16 over the international date line resulted in a 180 degree roll that was fast enough to render unconscious or kill the pilot, as the software got confused about teh orientation needed to keep the plane flying level.

There was also a flight of F-22s (real, not simulated) that lost all computer and communication systems and had to follow another plane to get home because of a software bug when crossing the international date line: http://www.dailytech.com/Lockheeds+F22+Raptor+Gets+Zapped+by...

chiph• 11 years ago

I heard a slightly different version of the F-16 going inverted - it was in the flight simulator during initial software checkout, and he flew into the southern hemisphere, when the plane flipped. Obviously a sign problem...

ufmace• 11 years ago

Imagine being the pilot doing the first real-world test. Point your jet fighter directly at the ground and let go of the controls, then trust that the software written by some guy you've never met will automatically avoid the crash for you.

ricardonunez• 11 years ago

This is fascinating stuff. Does anybody know the whole cost of this system? I only was able to find a pdf and it says that the seed money was $2.5 millions. If anybody is interested here's the link: http://www.nasa.gov/sites/default/files/337112main_Auto-GCAS...

boombip• 11 years ago

I found this PDF: http://www.globalsecurity.org/military/library/budget/fy2015... that says it cost ~2 million to integrate in 2013.

kingkawn3• 11 years ago

Why are we bombing Syria?

rufustherag• 11 years ago

Google 'isis' aalong with beheadings, rape, child slavery, sex slaves, burning people alive, burying people alive etc. Alternatively buy a newspaper from time to time.

kingkawn3• 11 years ago

Funny that you and many others got angry because I asked the question that you want to no longer have anyone ask.

Is each bomb going to kill ISIS, or might it do more? Then "why are we bombing syria" never stops being a relevant question to ask, and never one that is fully answered until the answer becomes that we are not.

kingkawn3• 11 years ago

Also there are lots of horrible regimes and atrocities around the world at all times. The reason we are bombing this one likely has nothing to do with any of the above, and so remains a valid question.

chrisbennet• 11 years ago

Jordan is bombing Isis in Syria.

Animats2• 11 years ago

The USAF finally went for that? It was first demonstrated in 1998, and has been used by the Swedish air force for years. Their slogan is "You can't fly any lower". Here's the 1998 writeup, copied from Aviation Leak: http://www.f-16.net/f-16_versions_article8.html

The technical paper: http://www.icas.org/ICAS_ARCHIVE/ICAS1998/PAPERS/182.PDF

The actions this system takes are drastic. Roll rates to 180 degrees/sec to get to wings-level, then a 5G pull-up. The pilot's helmet may be banged against the canopy. It's so drastic because flying 150 feet off the ground in mountainous terrain is normal procedure for fighters. If the system has to act to avoid a collision, that action has to be very aggressive.

Here's what it looks like to a pilot:

https://www.youtube.com/watch?v=aPr2LWctwYQ

Here, the pilot puts the plane into an insane bank and, as he says, "goes to sleep" and releases the controls.

spyder• 11 years ago

... and here is a longer video from NASA about their development of collision avoidance system that can work for regular planes too: https://www.youtube.com/watch?v=XWx6-aK8Ick

Animats2• 11 years ago

That's so NASA PR. About 80% of the stuff in that video was not done by NASA. The F-16 auto-GCAS was a USAF/Swedish Air Force/Lockheed project. The NASA people are just reusing that technology on a model aircraft.

naz• 11 years ago

The Stuka had a slightly less sophisticated version of this in 1935:

http://en.wikipedia.org/wiki/Junkers_Ju_87#Diving_procedure

cbr• 11 years ago

Significantly less, but still impressive for its purpose.

Ground Collision Avoidance System ‘Saves’ First F-16 in Syria

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