Ron,
No offense but picking the wing tip up verses a distributed wing load achieves
different bending loads on the wing. I reject your wingtip test as definitive.
The outboard wing is nearly 40 square foot, and at 13 pounds roughly per square
foot the tips can load up to about 520 pounds distributed between the two
wings with most of the load forward of the main spar at an angle of about 10-15
degrees off vertical and forward. So simply lifting the tip doesn't hack it
for a deflection. I do agree that the ailerons may droop a bit at maximum G.
However, ask yourself, are you pulling 3.8 Gs normally at the stall. No most
do stalls at or near one G and accelerated stalls normally no higher than 2-3
Gs so if there is any bending down of the ailerons it would be consistent
between
wings. This is nothing more than an academic exercise and doesn't really
apply to building and flying in my opinion.
I never modify/fly a plane by adding reflex or modifying the wing without flight
testing and in consort with the designer, I again reject the idea of
pre-modifying
based on non definitive flight tests. If you choose to experiment, please
note that if you have flight difficulty remember to warn readers of your non
standard modification first.
The wing at zero sweep and washout designed is excellent. You may need to read
between the lines on my stall synopsis a bit. The root stall tends to move
slowly
to the tip unless the wing is warped or damaged and repaired out of rig.
Most tapered wings have between 2-4 degrees of twist to make this happen.
Again,
if one does not maintain coordinated flight at the stall you will be surprised
in any airplane when a wing drops. I'll add more on this in another reply
on aileron use and rolling off of the Europa in accelerated stalls.
Sorry I don't experiment on a perfectly good wing.
Best Regards,
Bud Yerly
-----Original Message-----
From: owner-europa-list-server@matronics.com
<owner-europa-list-server@matronics.com>
On Behalf Of rparigoris
Sent: Monday, January 24, 2022 10:52 AM
Subject: Europa-List: Re: Stalls & spins - any test pilot pireps out there?
Hi Bud Thank you for great information on Stalls and Spins! I paid careful
attention
to making sure the pivot for aileron was precisely aligned on fuse and wings.
No slop. No change in free play.
That said if I pick up on the tip of each wing by about 300 lbs using my pump
jacks,
the wing deflects upward as expected and the ailerons droop some (wash in).
Did you ever fly with 1/8" reflex which would probably become no reflex when
pulling
2 Gs in an accelerated stall compared to no reflex at 1g which will probably
become 1/8" wash in when pulling 2 Gs and seeing if the spin behavior is
more benign?
I'm pretty certain Don Dykens incorporated just the right amount to keep the
tips
flying when stalling. Did he count on wash in occurring when pulling Gs? No
question that ailerons set even work, but for a newbie Europa Flyier flying
an unproven aircraft, does 1/8" reflex taint things in favor of a more docile
spinner? I have an XS, not Classic. Thx. Ron P.
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