Ramy wrote:

This is all correct when you have enough altitude that all you need to
decide is how much higher you should climb to fly faster, a typical
contets scenario. I was thinking more of final glide at the end of the
day when you trying to stretch a marginal glide to try to make it home
against significant head wind (think final glide to Truckee from the
north end of the Pine Nuts or Airsailing). Normally you would put MC=0
when you want to maximize your glide, but if you have 20 knots head
wind a setting MC=1 will be better. Sounds like GPS-LOG is doing this.


Well... not exactly. You should always put MC=0 (setting it higher
would give you safety margin as you can slow down) Flight computer
should give you altitude and speed corrected for wind for the MC
setting you request. If you have the altitude, then it can calculate
maximum speed to reach destination and from speed MC. GPS_LOG
recalculates speed (and MC) in final glide continuously based on
altitude and you can display it if you wish, or you can display other
types of calculated speeds.

Just remember that all instruments lie, and the ones that predict
something lie the most.

Cheers,
Henryk