In message , AndersP
writes
snip

The risk of a slippery glass glider catching up with the towplane
during decent is simply not worth it.
Snip

Opening the airbrakes works very well at stopping the glider catching up
the towplane... Descending on tow (though not all the way down) was one
of the things I had to do on my final flight before going solo.

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Surfer!