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I've just been forwarded a video about a jetfighter landing with just one wing and I wonder if this could indeed be true.

Here's the link to the video: One-Winged F 15 Crash Landing Video (landing starts at 2:45)

My understanding of flight is that the airplane would have started to spin out of control because the lift on the still intact wing would be much higher than on the other side, causing the plane to flip over without hope of recovery.

But then again this airplane has two vertical stabilizers and side rudders, also two rather big horizontal stabilizers. And jetfighters can fly upside down, anyway. So perhaps that, combined with the shape of the plane, would suffice to stabilize the flight somehow?

Sam I Am
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    If you pay attention to the video the pilot also notes that he was flying with the afterburners and came in for a landing at over 200 knots. The high speed involved also likely had a lot to do with the landing as well. – rjzii Jun 19 '12 at 21:47
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    He landed the plane like you would fly a bottle rocket with no wings. Increase thrust to maximum and aim upwards. – Eric Leschinski Mar 07 '14 at 16:04
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    Just to add the wiki page describing the incident for reference: http://en.m.wikipedia.org/wiki/1983_Negev_mid-air_collision – Nadav Mar 07 '14 at 16:06
  • Jamiec's great answer explains the real life event behind this interview. The flight sequences in the video are clearly CG/reenactments though. – Josh Wright Mar 07 '14 at 20:46
  • I remember when this happened. This is one of the first fly-by-wire planes and supposedly the pilot adjusted the controls in such a way that the plane continued to fly. I was in the military then and remember them saying that other pilots were being trained in what he did. In fact I remember that the actual settings were programmed into the computer to allow pilots to 'press a button' if they ever found themselves in the same scenario. In any case, I can accept that it is true based on the concept of fly-by-wire, where the plane is essentially unstable and can not fly without computer. This le –  Mar 07 '14 at 19:54
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    Zivi Nedivi was actually my boss for a while there... I can vouch for this as far as I'm concerned – damageboy Mar 08 '14 at 07:04
  • The thing I actually am sceptical about here: he says he stopped ~10m before the net, but I don't see a net in the video? – Jon Story Jun 09 '16 at 15:48

1 Answers1

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TL;DR; The F-15 is somewhat unique among current airframes, in that its body shape and size induce a certain amount of lift. That extra lift, along with the speed achievable with afterburners, allowed this aircraft to recover from an incident which would bring down most other aircraft.

The fact that we have a picture of this aircraft on the ground and intact, should be the first hint that this is no hoax.

IDF/AF photograph - one-winged F-15 on the ground

To quote the pilot, Zivi Nedivi:

At some point I collided with one of the Skyhawks, at first I didn't realize it. I felt a big strike, and I thought we passed through the jet stream of one of the other aircraft. Before I could react, I saw the big fire ball created by the explosion of the Skyhawk.

The radio started to deliver calls saying that the Skyhawk pilot has ejected, and I understood that the fireball was the Skyhawk, that exploded, and the pilot was ejected automatically.

There was a tremendous fuel stream going out of my wing, and I understood it was badly damaged. The aircraft flew without control in a strange spiral. I reconnected the electric control to the control surfaces, and slowly gained control of the aircraft until I was straight and level again. It was clear to me that I had to eject. When I gained control I said : "Hey, wait, don't eject yet!" No warning light was on and the navigation computer worked as usual; (I just needed a warning light in my panel to indicate that I missed a wing...)." My instructor pilot ordered me to eject.

The wing is a fuel tank, and the fuel indicator showed 0.000 so I assumed that the jet stream sucked all the fuel out of the other tanks. However, I remembered that the valves operate only in one direction, so that I might have enough fuel to get to the nearest airfield and land. I worked like a machine, wasn't scared and didn't worry. All I knew was as long as the sucker flies, I'm gonna stay inside. I started to decrease the airspeed, but at that point one wing was not enough. So I went into a spin down and to the right. A second before I decided to eject, I pushed the throttle and lit the afterburner. I gained speed and thus got control of the aircraft again.

Next thing I did was lower the arresting hook. A few seconds later I touched the runway at 260 knots, about twice the recommended speed, and called the tower to erect the emergency recovery net. The hook was torn away from the fuselage because of the high speed, but I managed to stop 10 meters before the net. I turned back to shake the hand of my instructor, who had urged me to eject, and then I saw it for the first time - no wing !!!

Source: http://www.uss-bennington.org/phz-nowing-f15.html

As to answering how this aircraft was able to stay airborne with little of its starboard wing intact, the source above hints at the answer:

McDonnell Douglas attributes the saving of this aircraft to the amount of lift generated by the engine intake/body and "a hell of a good pilot".

Looking into this a bit further shows that the wide-fuselage design of the F-15 indeed provides a certain amount of lift on its own:

Fighters like the F-15 Eagle also produce substantial lift from the wide fuselage between the wings. Because the F-15 Eagle's wide fuselage is so efficient at lift, a F-15 was able to land successfully with only one wing, albeit under nearly full power, with thrust contributing significantly to lift.

Source: http://en.wikipedia.org/wiki/Lifting_body#Body_lift

The last line there being important - lift increases proportionately to thrust:

lift force = ½ρV² × coefficient of lift × area

Source: http://www.av8n.com/how/htm/4forces.html

So although initially the aircraft entered a descending spiral (presumably for much the reason you stated - differential lift from the intact vs missing wing), the pilot was able to stabilise this by increasing his airspeed to generate enough lift to halt the descent, and enough airflow over the control surfaces (ailerons & rudders) to halt the spin.

"Hell of a good pilot" appears to be the understatement of the century! This guy now attains the "Sullenberger" level of pilot-awesome for me.

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Jamiec
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    The Instructor was later seen to whisper something to the pilot, hand him something, and then bow deeply, after which he vanished from the face of the Earth. – Larry OBrien Jun 20 '12 at 18:11
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    The video in the OP also has pictures and an interview with Zivi Nedivi, so I'm not sure how this answer adds much to the question. Though I'm also not sure why the OP is skeptical here, what they are looking for in an answer that will convince them. – Sam I Am Jun 21 '12 at 00:28
  • Answer updated with more information on *how* this aircraft recovered. – Jamiec Jun 22 '12 at 10:18
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    What surprises me in this explanation is that when an instructor in the back seat see a lack of wing and says "eject!" that there is room for debate. I would have thought that (a) the instructor would have personally made the decision to push the ejector button for his own safety and that (b) that would trigger the pilot's ejector seat too, as a matter of course. – Oddthinking Jun 22 '12 at 13:15
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    Pilot in Command has the final say. Just because you have an instructor on board, doesn't mean he's in command. I assume Nedivi was PIC, and the instructor was probably re-evaluationg him. Im guessing he passed :) – Jamiec Jun 22 '12 at 13:17
  • @Oddthinking - Larian might be able to exlpain that one – user5341 Jul 11 '12 at 20:24
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    I was chatting to an aeronautics expert, and brought up this issue. While he hadn't heard of the incident, he pointed out in the video that the tail wasn't damaged. He explained that what was unusual about the F-15 wasn't that its body produces lift (which is common with many military planes), but that tail offers a lot more control than most designs. (I've no evidence here - just an unsubstantiated expert opinion.) – Oddthinking Jul 17 '12 at 14:13
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    @Oddthinking - When I wrote this, something in the back of my mind thought the F15 used elevons (Combined elevators and ailerons on the tailplane) but a quick look on wiki showed traditional ailerons on the F15. My point: I had thought the same thing; that the retention of control was due to the lack of damage to control surfaces. – Jamiec Jul 17 '12 at 15:09
  • @Oddthinking I can't find the video just now, but in it the pilot said that because of his seat and his instructor's seat, they could not see how much of the wing had actually ripped off. because they still had control they decided to land it. – flyingfisch Mar 07 '14 at 17:39
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    @Oddthinking- the F-15 has all-moving tailplanes (the horizontal tail) which provide not just pitch but [some additional roll control](http://www.f-15e.info/joomla/technology/airframe/62-horizontal-stabilizers). From what I understand, in this situation the fly-by-wire system was taking advantage of this to improve control. – egid Mar 07 '14 at 18:53
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    Should say "navigator" not "instructor". This is a two-seat F-15 where the navigator sits behind the pilot. In the video the pilot is clearly saying "navigator". – Guy Sirton Mar 08 '14 at 04:45
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    @Oddthinking also Wikipedia says: pilot Ziv Nedivi and *navigator* Yehoar Gal - not sure where "instructor" came from. – Guy Sirton Mar 08 '14 at 04:54