Mary: once again, we're talking about Precautionary Landings in a powered aircraft where there is an opportunity to inspect the intended landing area before committing to a landing. We are not talking about field landing in a glider, which is a one shot affair (as I found to my cost when I caught a tip on the stubble in a Pik20D many years ago
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Regarding MaxDrift (and MDR) calcs - I would hope that all or most PPLs who were trained in this country would be familiar with the simple sums needed to estimate drift (and groundspeed) when they learned how to fly accurate diversions. Likewise constant aspect approaches for PFLs, but I'm risking going off at a tangent. There must be loads of info on t'web about MaxDrift, MDR and Constant Aspect but we could start a thread on them if that would be useful.
HFD
(FWIW I stopped being a gliding instructor about 25 years ago, having first gone solo about 43 years ago (there were some big gaps!). Everything I've discussed in this thread has related to powered aircraft.