My gut tells me this aircraft has had an instantaneous, catastrophic structural failure or in flight breakup. The similarities to PA103, AI, UTA, TWA and the list goes on are unerringly similar. Just leave the aviat, nav comm aside for a moment.
There was an accident a while ago. To give you an idea of the forces involved in an in flight break up, the aircraft departed controlled flight when a vertical stabiliser separated from the airframe, resulting in a pitch up and an almost instantaneous acceleration from 1 to 20 G's. The aircraft suffered continued breakup and the test pilot was killed. The gear was torn away from the airframe which is how investigators determined the forces involved.
Now... IM NOT saying that is what happened here at all. But an almost instantaneous 20G acceleration is not good for anything...... but the reason i mention it is that the test pilot didn't get a distress call in and there was in instant loss of telemetry.