I'm stumbling over the calculation of the groundspeed and time in the PLOG. It seems to calculate the GS at the end of the leg, and use that to calculate the time for this leg. However, if it's a longer climb (say FL90), then for most of the time during the leg the GS will be significantly lower, and thus the time required for the leg significantly longer that what's in the PLOG.
Have tried it with a PA28 climbing up to FL90 and back down over roughly 40nm, and the PLOG shows 20mins req'ed for the climb leg, with a GS at FL090 of 130-ish kts, whereas climb speed is actually around 80kts and thus timing should be closer to 30mins (bit less as TAS increases with height).
Am I missing something?
Many thanks.