The limiting factor is not the winch, but the rope length which in turn
is related to the available runway length. A rough estimate is that the
height with no wind is about half the rope length.

Super cool video with an awesome launch. The hydrowinch site says
they have enough room on the spool for 10K of Spectra rope. I guess
if you have a 10k runway available,. you could get launched into
space! Well, not quite, but it would sure seem high compared to a
regular 2k launch.