Todd Pattist wrote:

And even if they will stay in a spin, U.S. certification
standards do not require that the spin be recoverable after
extended spinning (6 turns or 3 seconds) .

JAA standards require a recovery with the standard procedure after 5
turns. I wouldn't assume that the factories build an extra line of
gliders for the USA that won't recover, just to please the FAA. (I'm
talking of modern gliders here, Schweitzer's milage may vary.)

Stefan