Andy, how different is this from the definition of Standard Class? The FAI/IGC established it in the 1950s, the German glider manufacturers allegedly colluded in the 1960s to rewrite the rule about terminal velocity dive brakes, and each country's aero club can do whatever they want (as the U.S. did with flap timers around 1980 and again a few years ago to handicap older gliders).

Or "approved flight recorders", the definition of which varies widely from country to country.

Within the U.S., is it standards? Or enforcement?

I'll grant you a dispensation from the "don't post if you haven't flown" mandate to respond.

Chip Bearden
ASW 24 "JB"
U.S.A.