Unbelievable but true.......I guess what your eyes can't see, your heart doesn't believe. Sometimes this makes you achieve the impossible.

Unbelievable

What did the Pilot do to control the roll 
Aileron s up of the other wing 

few things that did not clearly come out in the video are:-

(a) in most modern aeroplanes 40% of the lift is produced by the fuselage, unlike older gen aeroplane where fuselage was supported by the wing here the fuse supports itself in some cases part of the wing loading too.

(b) You dont need two ailerons for roll, one is enough. You need to compensate the Aileron drag, which in a Fly by wire aeroplane like the F-15 the computer compensates

(c) wing fuse joint (which is also referred to as the glove in some cases) produces life too, so what you see as the wing is essentially a portion that is there to carry some fuel,electronics, house aileron for roll control and support 25%-30% of total lift. For a 9G capable aircraft, it is designed to produce lift = 9 times its weight, which means complete aircraft is capable of 9 times of its lift under 1G conditions, therefore 30% lift gone, the other wing and fuse could support the aircraft at higher speeds and higher angle of attack

That is the explanation

PS
I searched all over the internet to see if this explanation is beaten to death anywhere! sorry sir ! no! there aint any at any one place. for this info we need to come here, is it relevant to RC ? i leave that judgement to you

If one watches the entire video, a bit of the explanation is found towards the end. McDonnell Douglas engineers were baffled by what had happened and confirmed what rcpilotacro has to say. The F15's wide fuselage generated a lot of  lift to help keep the aircraft airborne.

My reason for posting this video was not to get into a discussion about how it could be done. I did it to admire the pilots flying skills and to also to prove the point of mind over matter. As the pilot says, "Had I known that the entire wing had been ripped off, I probably would've ejected immediately."

Too often, we give up without even trying - because the situation looks "impossible" - we take the easy way out. We follow footsteps of losers who say "It can't be done".

If you think you, you can. If you think you can't, you can't. Either way, you are right!

F-15 employs all moving horizontal tail plane for roll control which is huge. I guess it provides enough torque to negate the asymmetric lift. The pilot had one remaining aileron + twin rudders to balance the roll caused by the broken wing. Together with blended body wing + low wing loading, the AC was saved. JMT.

Cheers....

I just cannot fathom how a wing can get ripped off and the pilot remain "unaware" of it.

Gusty, your thoughts on this?

I saw a similar video 50CC plane's coming off in mid air and the R/C Pilot  still able to land it. So it takes skills to fly in such situation, either Fly By Wire or direct control.

i once had a massive fuel leak, other than a few feet behind the cockpit everything was misted with fuel in super fine form, in his case too the same thing has happened