On Monday, 3 October 2016 22:00:50 UTC+1, Jonathan St. Cloud wrote:
Does anyone use a safety altitude in their flight computers for final glide? If so why or why not?

I have reachable landpoints on the moving map identified in green. In order for the green to be at all meaningful I do set a safety altitude. That said, I am mindful of what safety altitude I have set and would take into account the factors mentioned by others in deciding whether to set off on final glide above or below that figure. (I also do a gross error check in terms of kms per thousand feet, and look at the glide ratio required which the computer shows taking into account the set safety altitude).

The basic rule for speed is to set MC for final glide to the actual climb rate achieved after centering in what is expected to be the last thermal. If in a good last thermal I do wind the MC up while climbing, to inform my decision on when to leave. It would not make sense to have that MC set at any time when you expect to have to find and center another thermal.