>>>>>>>>> Dave of Dave's Ercoupe Page wrote: Ed, I began flying sailplanes when I was 13 and I'm 49 now, I have moved up over the years (had a Mooney M20J before the Coupe) and have done a fair number of stalls, regular as well as accelerated over the years and some aerobatics. I've even intentionally spun a Tomahawk and lived to tell about it. Actually A Tomahawk isn't all that bad in a spin as long as you don't look back over your shoulder at the tail.
The ability of a Forney to stall is not something I've heard it is
experience. I feel quite confident in being able to identify a stall as
well as know the difference between normal stall and an uncelebrated
stall. I also assume that the CFI's who have done my BFR's knew the
difference too and were all surprised that it will stall. Mine has a
very mild right wing drop at the break and a stall can typically be
recovered in 50 feet, about the same as a 150. It does a nice
accelerated stall but does tend to roll off a bit more though. Remember
the Forney does have more up elevator that the 415. I have enough
elevator back there (yes, it is in specs) to nearly drag the tie down
ring on the tail when I flare for a landing.
When landing by myself (not in formation) I tend to do a full stall
landing (just the way I was taught). I've gotten the attention of at
least 1 Coupe Guru doing that. The Forney is still placarded as
"characteristically incapable of spinning". Mine does not spin but then
I've never really pushed the issue, it does a sort of spiral if left to
it's own devices.
The additional up elevator allows me to pull back till I feel the
additional back pressure from the spring (the spring comes into play at
the what would be the max up elevator for the coupe) so I can thereby
make a slow approach and still have enough elevator to flare and arrest
the sink. Makes for a fairly impressive rate of decent on final coming
in over an obstacle.
I can make a steeper approach than a lot of pilots in 150's are willing
to do. At 55mph indicated it comes down like a brick. The 150 in good
hands will make a steeper approach than mine but it needs to be in good
hands. The effect of the additional up elevator can be attested to by
Paul Prentice. I use to turn inside of him on a regular basis when
playing around.
Should there be any continued doubt about the stall issue I'm more than
willing to place money on it. I've won several bets with this little
plane on this issue along with spot landing capabilities and never lost
on a crosswind capability issue. So if you really believe it won't stall
and you would like to contribute to my retirement fund,,,,,,,,,,,,,well,
bring your wallet and come on down :-)
<<<<<<<<<
Well, Dave, I sure don't have your experience.
I'm interested in hearing more description of what you see and feel when
your Forney stalls. My 415-D gets a bit of break and drops the left
wing and would circle left if I kept the controls centered.
Since I do have rudder pedals, I've gone up to 8,000 feet (I'm also
naturally chicken) and tried cross-controlling the plane at full up
elevator. It gets squirly and bouncy but won't break into a spin. I
did this at various power settings up to about 2200 rpm after which my
chicken nature took over. Even at nearly full power, it wouldn't break
into a spin. But I sure got a lot of stall buffet and marginal control
and, at 2200 rpm, I couldn't hold a straight line but continued to
circle left.
Fact is, Coupes were designed to stall -- some. I'm told that Fred
designed the fairing between the wing and fuselage to give just the
behavior he wanted. When you get to low flying speeds the wing does
start to stall at the wing root. As you slow more, the burbling stall
develops more causing turbulence over the tail. As the tubulence over
the tail increases, it upsets the elevator's ability to push the tail
down further.
Let me try character drawing:
_
/ \
____________| |___________
| /| |\ |
|_________/_| |_\_________|
/ | | \
/ | | \
/ | | \
/ |_______| \
The stalled airflow does move out the wing some. But, before you lose
the smooth airflow on the outer part of the wing, the tail is _supposed_
to lose its ability to make the situation worse. It _is_ supposed to
bump and shake in the turbulence.
Yet, by design, it's never _supposed_ to develop a full enough stall to
spin.
As I've seen defined, a spin is a stall when one wing is more stalled
than the other, leading to rotation. That's what the Coupe is
_supposed_ to be incapable of doing. It's certified to maintain enough
control that it doesn't drop off into a spin. That is, of course, when
your plane is rigged right and within it's weight and balance envelope.
In my plane, I can't even make it spin when fully cross-controlled. I
sure do get that burble and break, though.
How does that compare to what you get?
--
Ed Burkhead
East Peoria, Ill.
N3802H, 415-D
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