"Peter Dohm" wrote in
:


"Bertie the Bunyip" wrote in message
.. .
"JGalban via AviationKB.com" u32749@uwe wrote in
news:7ec1fcb50fea9@uwe:

Ricky wrote:


I also remember being warned "no spin is exactly the same or
predictable, so DON'T do them solo! Was this just a warning from my
school so we wouldn't screw up their gyros or are spins indeed
possibly very dangerous inherently for some reason?


Sounds like the school didn't have a whole lot of confidence in
the spin
training they provided. Assuming you're within the proper weight
and CG envelope, spins should be quite predictable. Particularly in
something like a 152.

A local FBO will only allow spins in their Great Lakes aerobatic
trainers
(they also have Supercubs and Huskies) because the have cageable
gyros. I've often wondered if this isn't an Old Wives Tale. I've
been spinning my Cherokee on a fairly regular basis since 1994. The
gyros often tumble during spins, but that's never caused a
maintenance problem. I've still got the same gyros in the panel
that were there when I bought the plane 14 yrs. ago. They've never
been removed for OH and they're still working fine.


Holy Crap! That's amazing!

It definitely wrecks gyros. The one place I worked that had no non
gyro airplanes had one airplane ( cherokee) for spins and it's gyros
barely showed any interest at all.
I suppose it depends on the quality, but it is defnitely not an old
wives tale.


Bertie

My recollection is that a "normal" spin entry would tumble the gyros
in a 150M, but not in a 152. Apparently, if my recollection of the
gimbal limits is correct, the 150 dipped through 80 degrees nose down
on the entry and the 152 did not.

Well, that seems kinda strange! The airframes are essentially the
same.The CG would probably be a bit different and maybe they've riggd
the airplane differently ( decalage) I haven't got a lot of time in a
152 and in fact I don't think I've ever taught in one. I can't even
remember what a Cherokee spins like..


There seems to be a wide variation in the spin entry for various
aircraft, even when the entry is not from an accelerated stall, and
there are also a variety of non-tumbling gyros (in addition to
gageable viarieties) in the GA fleet. All of the cageable gyros that
I have personally seen were the old fashioned varieties (gull-wing
horizons and those old DGs that looked like the whiskey compass in the
windshield) which would tumble on any excursion through 60 degrees of
pitch or roll if not gaged.


True enough. sounds plausible, allright. I don't know though. Most of
the airplanes I used to spin had wrecked gyros in no time, though.

I have never personally seen any of the newer type gyros which were
cageable, although I presume that they exist. In any case, the newer
types (which can now be close to 40 years old) are certainly more
rugged than their predecessors.

I've seen them for sale OK. New ones. They're megabucks.

Please treat this as a request for information and comment.


I'm not that scary!



Bertie


Bertie