If the fpm shows a loss, that's a stall yes?

No. Not necessarily. A stall is when the airflow separates from the
wing (it generally happens piecemeal). Lift can deteriorate even before
that happens.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
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