Let's remind ourselves that the design requirements for all single engined aircraft certified under CAR 3 or FAR 23 must comply with 23.221 (1).....:
(iii) [ It must be impossible to obtain unrecoverable spins with any use of the flight or engine power controls either at the entry into or during the spin; and
I have spun many certified types during flight testing, and never had a problem. The differences I have seen, seem to be will it come out on it's own, or do I have to actually work to recover it. The Cessna 206 with an aft C of G did require aggressive recovery, and the 185 floatplane was similar. That said, this is a "don't try this at home folks" situation, the fact that spinning is possible in these aircraft does not mean that you won't be getting close to limits during recoveries. When I test, I have an accelerometer, so as to be precise when recovering from resulting dives.
My spins earlier this month were in a Grand Caravan. It is magnifently designed from a flying point of view, though again, the C of G position greatly changed the spin recovery characteristics. Maximum rate of descent during recovery, 9200 FPM, while seeing 2.8 G at .9 Vne.
Here's a tail video camera snapshot (im still trying to figure out how to edit 15 seconds, out of an hour long video of the second spin flight!)
