Ahh.
But TC is referencing momentum.
He implies that it is the momentum of the differently-sized (mass being the only applicable measure of size in momentum) is what makes one piece continue on, and the other, heavier piece crash sooner.
His argument relies on mass. Ballistic trajectories do not care about mass.
Well, if that's what he's implying, he's wrong. However, for reasons that I've given, his intuition that the physics of the situation demands divergent trajectories, is correct. He's just got the specifics wrong.
You may be right, but absent a simulation, I'll reserve judgement. For one thing, why assume that the engine would travel with it's air intake forward, as in normal flight? Almost certainly, an explosive detachment would send it spinning. Which suggest an additional dynamic leading to divergent trajectories, like what makes a curveball curve.In regards to aerodynamic drag, a jet engine is considerable less streamlined than an airframe. Especially considering its lighter weight than the airliner.
It has to ram air in to the intake. A nice, but, flat surface, instead of a rounded one like ain airliner nose. Think of moving your hand through water with the flat facing the direction of motion versus with the side facing the direction of motion.
As for the argument that the trajectories of the engine and fuselage would change if the plane were hit by a missile, well, if TC wants to use that, he can. All he has to do is provide evidence a missile hit the plane. Which he cannot do, since there is absolutely no evidence of a missile.
Absent direct evidence of a missile, he can still make a plausibility argument. Also, if separate trajectories of engine and the rest of the plane are confirmed, what is more likely - a missile or a bomb? AFAIK, there are no baggage compartments in an airplane wing. So, if you suppose a bomb, you have to assume that it was planted before takeoff.
Or should we suppose that it just fell off? Well, if pilot action can result in nasty aerobatics, I suppose that possibility should be checked out. Then again, maybe this would be a job for NIST. They can make anything fall apart!! (On paper, anyway...)
Instead, he's relying on misinterpreted eyewitness testimony, and an ignorance of physics.
I'm not familiar with the other witness testimony.
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BTW, when I mentioned relative changes in momentum, I was thinking in terms of scalar momentum. However, in the general case, one expects the direction of the resultant momentum vectors to diverge, also.