[Updated] How Did an F-35 Fighter Jet Go Missing While on Autopilot?

[Flyboy]

... you guys never heard of the Cornfield Bomber, did you?

In 1970, an F-106 Delta Dart interceptor went into a flat spin during a training flight. Pilot fought it down to 15,000 feet, including deploying the drag chute to try and force the nose down. No luck. Dude punches out because by all rights the plane should be unrecoverable.

And yet, by ejecting, the plane pulled out of the flat spin. The change in CG, aerodynamics, and the rocket blast from the ejection seat caused the plane to recover, and given that part of the process the pilot went through was to trim it to a low-speed configuration and throttle back, it happily belly landed in a nearby cornfield.

Kicker of the whole thing is, they pulled the plane out of the field, shipped it to the maintenance depot, and they fixed it up and returned it to service, where it served the rest of the career of the type in 1986.

That exact airplane now sits in the National Museum of the US Air Force.

So yeah, punching out of a seemingly dead plane and having it go zombie isn't unheard of. Not going to pass any judgement until we hear more about the circumstances leading to his ejection.

That said, the fact that it's an F-35B, the STOVL variant, is interesting, because iirc, there's an automatic ejection seat initiation system that is supposed to detect a failure of the lift fan and eject the pilot, as there wouldn't be enough time for a human to react before the plane flipped over. Not saying that's what might have gone wrong, but it's a possibility that is unique in active-service aircraft.

 

[DaveC426913]

...in the mean time, it is saving $42,000 per flight hour - and with the Federal budget process and F-35B production already maxed out, it will be years (and likely thousands of lost flight hours) before it is replaced.

This gives me the mental image of a counter running all the time any plane is in the air, ticking over at 11.67 cents per second for each plane. I imagine they have a budget for any given military engagement. What if that budget runs out?

Time for a reimagining of THX-1138?


^{(If you don't get this reference we can't be friends.)}

 

[Vanadium 50]

an F-106 Delta Dart i

If we are going to discuss the Century Series, why not the F-104 Lawn Dart?

If you want to own a F-104, what do you do? Buy a plot of land and wait.

 

[Tom.G]

I thought it was us New Englanders that measured distances in units of time.

Not quite the only ones. We here in Southern California are familiar with the term, especially during the three-hour long "rush hour."

 

[Vanadium 50]

My favorite directions when I lived in New England was "Well, if I were going there, I wouldn't start from here."

 

[russ_watters]

What if that budget runs out?P

The plane shuts off and the pilot has to eject.

 

[DaveC426913]

So it travelled about 64 miles on auto. At, say, 500mph That'd be about 8 minutes.

Detours, according to the article:
"Traffic traveling north on Old Georgetown Road should turn right on Midway Road, left on Baptist Road, left on Bartells Road and right on Old Georgetown Road.

Southbound traffic should turn left on Bartells Road, right on Baptist Road, right on Midway Road and left on Old Georgetown Road."

... suggest the debris field is right about here:

33.7531, -79.5746

To match that detour area, the debris field would look something like this:

 

[DaveC426913]

News article:

https://digg.com/digg-vids/link/f-35-crash-witness-williamsburg-county-DO7XFNrJp0

This guy, whom the reporter shows as living at this address, heard it over head while he was shaving.

Randolph White says "I was in the bathroom takin' a shave and I heard a screechin' sortta between a screech a whistle ... AAAAAAAAAAAAAA!!!!!!! ... * then I heard a boom!"

*_{Sortta loses something in the translation. Gotta hear it for yourself.}Here's a capture of his house from the news clip:

And here is Google street view:

That's at 33.7599, -79.5781

^{Debris field is estimated.}

(I hope this doesn't qualify as doxxing. This is basic Google maps stuff.)

 

[Baluncore]

(I hope this doesn't qualify as doxxing. This is basic Google maps stuff.)

Judging by the mast, antenna and rotator, he is a ham radio operator, callsign?

 

[Vanadium 50]

NBC reports that eyewitnesses say the plane was flying inverted. I am not sure what to make of this - determining the orientation of a plane, especially an unfamiliar one, is non-trivial, especially when it is far away. But that's what they are saying.

 

[DaveC426913]

... the plane was flying inverted...

...determining the orientation of a plane, especially an unfamiliar one, is non-trivial...

Nonsense. Everyone who saw Top Gun became an instant expert on the subject.

 

[Tom.G]

determining the orientation of a plane, especially an unfamiliar one, is non-trivial,

Aw, come on! If the tail do point at da ground, it be downside-up.

 

[DaveC426913]

Let the memes begin...

 

[berkeman]

NBC reports that eyewitnesses say the plane was flying inverted. I am not sure what to make of this - determining the orientation of a plane, especially an unfamiliar one, is non-trivial, especially when it is far away. But that's what they are saying.

Lordy, can you imagine if the "mishap" were that the plane flipped inverted at 1000' and the pilot could not recover it? Deciding to eject inverted at that low altitude would be a tough decision...

 

[nsaspook]

Lordy, can you imagine if the "mishap" were that the plane flipped inverted at 1000' and the pilot could not recover it? Deciding to eject inverted at that low altitude would be a tough decision...

Thank goodness it's got a great zero-zero seat.

 

[Vanadium 50]

great zero-zero seat.

If you are inverted, doesn't a zero-zero seat shoot you into the ground?

 

[berkeman]

If you are inverted, doesn't a zero-zero seat shoot you into the ground?

Yeah, that's what I was wondering. Hopefully it has the "brains" to vector you sideways and up as soon as you clear the plane, but who knows. I'm off to Google...

 

[berkeman]

And Google led me straight to Wikipedia...

The minimal ejection altitude for ACES II seat in inverted flight is about 140 feet (43 m) above ground level at 150 KIAS, while the Russian counterpart – K-36DM has the minimal ejection altitude from inverted flight of 100 feet (30 m) AGL. When an aircraft is equipped with the NPP Zvezda K-36DM ejection seat and the pilot is wearing the КО-15 protective gear, they are able to eject at airspeeds from 0 to 1,400 kilometres per hour (870 mph) and altitudes of 0 to 25 km (16 mi or about 82,000 ft). The K-36DM ejection seat features drag chutes and a small shield that rises between the pilot's legs to deflect air around the pilot.[12]

https://en.wikipedia.org/wiki/Ejection_seat

 

[Vanadium 50]

"Russian counterpart" - I am imagining Boris and Natasha saying "Seat automatically buries pilot. Saves cost of funeral."

It's an interesting safety question - seat design can probably make some incidents have a much better outcome at a cost of making some other outcomes worse. I suppose by now there is unfortunately enough data to make an informed engineering choice.

I presume that these days avionics are sufficiently advanced enough to decide on their own to eject the pilot. Yes, it has an element of HAL9000 about it, but at 9g's or more the pilot may be in no condition to do it herself.

* Yes, I know they were Potsylvanian, not Russian.

 

[.Scott]

If you are inverted, doesn't a zero-zero seat shoot you into the ground?

Yes, but most people don't do it that way.
It's easier to do it directly under an I beam in a hanger.

 

[Baluncore]

The possibilities are endless here. We do not know if the ejection was voluntary, or if the avionics ejected the pilot. To be flying upside down on autopilot, suggests that the cruise state was reached via an unexpected path.

Faulty software is one explanation, reliable software is another; since the aircraft partially recovered normal flight after the ejection event.
We will have to wait for the accident report to leak from the military investigation.

 

[DaveC426913]

or if the avionics ejected the pilot.

What?? This is a possibility???

What if he was picking his nose at the time??

 

[Vanadium 50]

We will have to wait for the accident report to leak from the military investigation.

These usually are made public, with some redactions, usually names.

However,

• We don't know the plane was inverted. Just that some non-expert witnesses reported it.
• We don't know why the aviator ejected.
• We don't know if or when the aircraft fires the ejection seat on its own. Just that such an action is technically possible when it wasn't so in the past.

I am not an aviator, but I find it plausible that a modern fighter aircraft can, in good weather, flight straight and level to the nearest pre-programmed landing area and safely put thge plane down, all with a good probability of success. I find it less plausible that the plane can recover on its own from an abnormal condition and do this, and as such expect that this feature on this airframe is intended to be used rarely.

In short, just because you can, doesn't mean you should.

 

[DaveC426913]

It is not clear to me whether these witnesses saw the plane inverted ejection or after ejection.

I can certainly understand the latter scenario, and that is what i had been assuming until yall started discussing inverted ejection.

 

[.Scott]

In previous US fighters, ejection was commanded by the pilot through mechanical means. I can't image the ejection decision being made by software because if the pilot does not prep himself, the injuries could be severe or fatal.
According to reports of the 911 conversation, the pilot reported "I ejected" and later reported an "aircraft failure".

Since the plane continued on for about a minute after the ejection, I would guess that it was more-or-less upright during the ejection, but rolled into inverted flight afterwards.

The pilot reported parachuting from 2000 feet. The military has reported the mishap as occurring at 1000 feet. The air station is on the coast at an elevation of about 37 feet, so there is no big difference between MSL and AGL elevation numbers. More likely, the pilot managed an unplanned climb to 2000 before ejecting.

 

[DaveC426913]

I am not an aviator, but I find it plausible that a modern fighter aircraft can, in good weather, flight straight and level to the nearest pre-programmed landing area and safely put thge plane down, all with a good probability of success.

I know nothing. Is this really within the realm of plausibility in modern aircraft?

I mean, I know commercial aircraft practically land themselves these days, but I assumed that word 'practically' to be doing some heavy lifting there.

 

[Baluncore]

I know nothing. Is this really within the realm of plausibility in modern aircraft?

Stealth aircraft have ugly shapes that are difficult to fly safely, so the avionics keeps the plane safe by interpreting the pilot's requests and staying within the flight envelope (= departure resistance). It would not take much for the redundant avionics to recover automatically after an upset, or the autopilot to return to base and land without input from the pilot.
Wikipedia on the F-35: "Relaxed stability and triplex-redundant fly-by-wire controls provide excellent handling qualities and departure resistance."
Wikipedia on the F-117: "It is aerodynamically unstable in all three aircraft principal axes and thus requires constant flight corrections via a fly-by-wire (FBW) flight system to maintain controlled flight."

 

[DaveC426913]

Stealth aircraft have ugly shapes that are difficult to fly safely, so the avionics keeps the plane safe by interpreting the pilot's requests and staying within the flight envelope (= departure resistance). It would not take much for the redundant avionics to recover automatically after an upset, or the autopilot to return to base and land without input from the pilot.
Wikipedia on the F-35: "Relaxed stability and triplex-redundant fly-by-wire controls provide excellent handling qualities and departure resistance."
Wikipedia on the F-117: "It is aerodynamically unstable in all three aircraft principal axes and thus requires constant flight corrections via a fly-by-wire (FBW) flight system to maintain controlled flight."

Sure, but find an airport and land?

 

[Vanadium 50]

Why is finding an airport hard? The military practically invented GPS. Airports - or more likely Naval Air Stations - don't move very fast,

 

[DaveC426913]

Why is finding an airport hard? The military practically invented GPS. Airports - or more likely Naval Air Stations - don't move very fast,

No, I get it. All the pieces are there, I am just having trouble imagining the reality of a pilot telling his plane to land itself a hundred miles away and then hunkering down for a nap, to only wake up when it taxis to a stop.