You refer to the Mountain Home Crash I assume
Yep, that's the one. Trying to work out the
altitude to commence a manoeuvre which needed a given
Height above the runway to complete.
Use QFE, just look for the correct number on the dial; same number every time. Use QNH then you have to do a sum - albeit fairly simple - then look for this number on the dial. Different number at each venue. Get the sum wrong and... Well it made a great photo!