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If you make an effort to escape a black hole, would your free fall velocity be slowing down? It is known that you can't escape once you passed event horizon. But is it possible to slow down? Or should I make a sample numbers. The escape velocity where you stand is $1,5 c$, your free fall speed at the moment is $0,75 c$. If the pilot start to begin escape attempt with $0,6 c$ in the normal world, how much is the free fall speed now? Or perhaps instead of slowing down, the free fall become faster now, because it turns out that there is only one direction in the black hole??

Kenneth Kho
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There is no such thing as an "escape velocity" inside the black hole, because inside the coordinates $r$ and $t$ are interchanged. This means that the flow of time is represented by decreasing $r$. So whatever rocket thrust you have, you can't even hover at $r = const.$

You can however optimize your survival time to a certain degree:

https://arxiv.org/abs/0705.1029v1

No Way Back: Maximizing survival time below the Schwarzschild event horizon Authors: Geraint F. Lewis, Juliana Kwan Abstract: It has long been known that once you cross the event horizon of a black hole, your destiny lies at the central singularity, irrespective of what you do. Furthermore, your demise will occur in a finite amount of proper time. In this paper, the use of rockets in extending the amount of time before the collision with the central singularity is examined. In general, the use of such rockets can increase your remaining time, but only up to a maximum value; this is at odds with the ''more you struggle, the less time you have'' statement that is sometimes discussed in relation to black holes. The derived equations are simple to solve numerically and the framework can be employed as a teaching tool for general relativity.

timm
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