B-50(?) + X1

romeomike wrote in :

Bertie the Bunyip wrote:



Like DC6's and Connies and such? Oh yes, they definitely were. It was
a requirement of the period. The old ATC system was the same
regardless of the aircraft size and was in effect until the late
forties. I believe the last aircraft to be certified under that
system was the Fokker F-27. There has to be some sort of spin testing
even now. I've done full stals in jets after deep maintenance, so
they had to have had some exploration of spin entry tendencies, but
the old airplanes were spun, regardless of size, if they could be
spun. I think the only US certified airplanes exempt were the
Ercoupe, the General Skyfarer and the Gwynn Aircar, all because they
couldn't be spun. I know someone who works at Boeing,or rather did,
and I've often wondered how deeply they went into it with the current
crop of airliners. I'll ask him next time i talk to him.


Bertie


Interesting. Now I'm wondering if the spin testing involved fully
developed spins or incipient spin entry.


I have the standard for the 1927-1949 Type Certificate lying around
somewhere. Going off memory but it calls for 6 turns both directions
with recovery achieved within one turn, or something similar. If the
airplane was unspinnable then this wasn't required. Looking through my
library for the requirements led me to another airplane eventually
certified without spin certification, the Alexander Bullet. The airplane
had huge difficulties with spins in it's earliest incarnation with four
of them crashing in spin testing. It was eventually drastically
reconfigured and was pronounced unspinnable and safe.
An airplane was an airplane back then and the cirteria was the same for
them all, large or small. On large multi engine airplanes, there was no
single engine performance requirement, for instance. Engine out
performance was more of a commercial selling point than a minimum
requirement, even in airliners.

Bertie