Perfect nosedive, engines off? How fast?
And of course, we can extend my previous crude argument to an engines-off perfect nose dive. The thrust provided by the weight will be three times that previously provided by the engines, giving a descent 1.7 (square root of 3) times faster than speed in level flight.
So the engines wouldn't really add much (1.7 to 2)
Once again, presumably break-up would supervene, making it all academic ?