Ron Natalie wrote:
: All the 140's were approved in the utility category up to 1950 lb gross weight.
: The 150 and the 160 were only certificated in the normal category (making
: them not spinable). Might have been that the empty weights crept up so
: high as to make the CG envelope of the utility category fairly unusable.
: I know that my Navion has a utility envelope that's only places gross only
: a couple of hundred pounds over the empty weight...I could only get in it with
: minimal fuel and no passengers/baggage.

The Cherokees have a pretty wide CG envelope, but normally operate
very far forward CG. I have done the calculations and determined that
it's *impossible* to aft-load the thing and stay under the 200 lbs in the
baggage compartment (min fuel, 70 lb pilot, 200 lbs baggage and back seats
full to gross).

Funny thing about the spins is that in the 140 manual, they don't
actually say spins are approved on so many words, but rather that spins
are not approved in 'Normal' category. I remember reading somewhere that
a test pilot was killed in the Cherokee certification when a spin turned
into an unrecoverable flat spin. Probably operating in the aft CG region
outside of 'Utility.'

I can't imagine any difference between the 140s and 160/180 in
spin characteristics. Minimally different engine weight, but perhaps the
battery further back changes moment of inertia?

FWIW
-Cory


--
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* The prime directive of Linux: *
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