Can anyone shed some light on some speeds that I noted from the FMS on a flight I did this morning.
The holding speed ( at FL390) was 220kts. The s/e drift down speed was 231kts, and the Vref 40 speed +100 was 236kts.
From what I have read in the 737 manual I would have thought that the VMD could be obtained from the s/e drift down page or approximated from Vref 40 by adding 100kts.
Bfisk stated that VMD could be obtained from the hold page but I wonder if this is true for our update 10.8 FMC because it seems too slow to me.From experience I imagine that 220kts would have been on the back of the curve and quite "speed unstable".
Any ideas about how those speeds are derived and if any of them are VMD would be appreciated.
Last edited by framer; 24th May 2013 at 12:13.