How Quickly Do Black Holes Form?

Why escape velocity changes on collapse? It shouldn't, isn't the mass remaining the same? The problem is the blast - the spaceship speed must be equal or bigger than blast's speed or you are dead earlier or later. Btw, what is the speed of the blast?

More Star Trek talk! Love it! As for my favorite blackhole story, hmm, not sure. I like the Stargate SG1 episode where one of the other teams was trapped by a blackhole. The image on the screen of the other team frozen in time (time dilation at work) was chilling.