Max demonstrated crosswind….who came up with that?
Before an airplane is type certificated by the FAA, it must be demonstrated in flight to be satisfactorily controllable with no exceptional degree of pilot skill or alertness in 90° crosswinds up to a velocity equal to 0.2 VSO. This means a windspeed of two-tenths of the airplane’s stalling speed with power off and landing gear/flaps down. Regulations require that the demonstrated crosswind velocity be included on a placard in airplanes certificated after May 3, 1962.
Read it for yourself on page 8-16 of the Airplane Flying Handbook available at-