I was studying gliders and how they fly. There is a point that's not clear to me: why does using water ballast improve the performance/speed of a glider? If I understand correctly, my glider jumps from one thermal to another more quickly with ballast than without.

How can more weight improve speed?

Thanks Ale

  • 1
    $\begingroup$ Yes I would say this is a dupe of the linked answer and it'll probably be closed. It's a long read, but the short answer bottom line is ballast raises the speed at which you have your flattest glide and this helps you spend less time in sink between thermals, therefore less aggregate altitude loss and more ground covered. You live with the higher sink rate penalty while thermaling during mid day. Late in the day when the lift gets weak and winds diminish, your priority becomes lowering your sink rate so you can climb in weak lift to make it home, and you dump the ballast. $\endgroup$
    – John K
    Mar 7, 2020 at 18:56
  • $\begingroup$ Welcome! Please see the linked question. If it doesn't provide a good answer for you, feel free to edit this question. $\endgroup$
    – Steve V.
    Mar 7, 2020 at 19:43


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