In that video, the aircraft has engines running and the nose of the plane is still attached to the rest of the fuselage.
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That wasn’t my point. My point was that a plane can gain altitude even after a rear shift in the center of gravity.
Only that , like a rock, if it's trajectory is on the upward curve of an arc, it will carry as far as momentum vs. gravity allows.
A cannon ball continues upward after it leaves the cannon barrel, but it only continues upward for so long, then it arcs back down. A cannon ball has little drag. A blown up airplane had a lot of drag, and no lift.
The amount of altitude something like that would gain is still based completely on a ballistic path with the addition of major air friction due to ripped open fuselage and wings/elevators/rudder/etc.
The length of time it could continue 'upward' and the altitude gain are miniscule.
In that video, how long after the load shift did the plane tilt up and completely stall ? 2 seconds ?
That's about how long TWA800 could have 'climbed'.
“My point was that a plane can gain altitude even after a rear shift in the center of gravity.”
No, it cannot; especially not thousands of feet in altitude at 13,000 feet.