Great write-up Bud...... how does the XS do in heavier rain?
> On Aug 14, 2019, at 8:32 PM, Bud Yerly <budyerly@msn.com> wrote:
>
> Chris,
> Getting the leading edge profiled correctly was a bit of a problem in the C
lassic foam wing. It comes down to a good long block and a root and tip tem
plate and of course a good eye. Technique on rolling the leading edge by ro
lling off the edge at a 45 gives a uniform leading edge. The XS is out of t
he mold pretty good. Though I=99ve seen wings built on saw horses tha
t were a bit wonky, but trimmed out OK. Good flat tables are the best wing s
kin gluing jig.
>
> Attached is my LSA vortex generator testing I did for the Europa LSA. Spe
aks for itself. I like these Aussie VGs. Great results after moving them a
round the plane was acceptable as an LSA or for STOL ops.
>
> Weight, CG, and wing smoothness are all essential for efficient cruising, b
ut so is cooling drag. Pay attention to sealing your cooling duct gaps. Se
e my Cooling discussions on my website. It is nice to get the benefit of an
increase in speed and cool better. Most of the drag on a light airplane is
cooling drag so make sure you follow the rule. Think like an air molecule t
hat is pretending to be a naughty teenager looking to get out of work. If t
here is a gap to escape work, they will rush to go through it, resulting in l
ow productivity, and drag. See www.customflightcreations.com for some of th
e other building and flying articles.
>
> Since the Europa wing is very well designed and up to 1450 pounds, has a r
easonable laminar flow and nearly perfect elliptic wing lift distribution, s
o aerodynamic gimmicks like wing fences, winglets, and VGs. I have not foun
d it necessary to fly with the wings in the raw or just primed and sealed. T
he stall of the Europa is slightly less abrupt than a typical series 6 airfo
il due to excellent leading edge contour. The best stall taming is with the
POH recommended stall strips as it adds great pre-stall warning feel prior t
o the actual break. You will find modifying the wing shape to improve flow w
ill be an exercise yielding nothing. I=99ve done tuft tests, and the w
ing tends to have a nice span wise root to tip stall progression providing t
he wings are built the same and square of course. The stall of an unmodifie
d wing begins separation at the root, the downwash over the stab decreases, t
he nose drops and the root begins to fly, then the nose rises and it repeats
. (See stall on youtube: Europa 159HR Flight.) The POH stall strip allows a
complete aft stick stall in most aircraft with the stick full back and a ge
ntle nose down rumble and shake. Don=99t let the nose wader as it wil
l rumble off opposite to the ball. Flaps down depends on the flap rigging.
The rumble begins only just prior to the stall and the nose drops like any o
ther large flapped conventional tractor aircraft. Adding VGs made for an ai
rcraft with excellent control but it sank like a rock at 40 KTS with no low s
peed warning. Like Buzz Lightyear, I was, =9CFalling With Style
=9D.
>
> Many pilots have never flown a light aircraft with the center of mass so n
ear the CG, so a little rudder, P factor, or a droopy flap really affects th
e yaw/roll in the Europa. Case in point, the nose is really pulled to the l
eft just at the stall break even at idle power! This results in a left wing
drop as one would expect. The stall strips give excellent feel approaching
a clean stall power on or off.
>
> Watch out for that old, I think I can make it better, which I found added w
eight, build time, and tweaking. Keep it light, maintenance accessible, and
smooth, and you will be rewarded.
>
> Get the family into the build, but don=99t be Captain Bligh, let the
m have fun and help (well for an hour or two when you need an extra set of h
ands). Remember, =9CAin=99t nobody happy unless Momma is happy
=9D!
>
> Best Regards,
>
> Bud Yerly
> Custom Flight Creations, Inc.
>
> Sent from Mail for Windows 10
>
> From: owner-europa-list-server@matronics.com <owner-europa-list-server@mat
ronics.com> on behalf of n7188u <chmgarb@gmail.com>
> Sent: Tuesday, August 13, 2019 12:06:26 PM
> To: europa-list@matronics.com <europa-list@matronics.com>
> Subject: Europa-List: Re: of interest
>
>
> Good points Graham and will probably do the items you mention.
>
> I am planning to paint only stabs, ailerons and maybe flaps white so I can
balance before first flight and not worry afterwards if I paint the whole p
lane. The rest will be primer and thin coat of sealer. This was a Lancair bu
ilder center did with their planes (Evolutions) we had here at our field.
>
> I used to fly a longEZ with VGs and it flew nice but I kept breaking them w
hen I handled the plane or cleaned it so my current one has none (and a GU c
anard!). But my EZ flies great, very docile and the canard stalls at 58 knts
so no complains. yes, it will pitch down in rain (or not take off in rain a
nd heavy) but I don't fly in rain often.
>
> Regarding the wing LE, how can you ensure it has the correct profile? Are t
here coordinates for this airfoil? Even with the coordinates it sounds that i
t would be challenging to ensure the entire span is accurate or do you check
at some discrete span points and then ensure the thing is fairly smooth in b
etween?
>
> Regards,
> Chris.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=490843#490843
>
>
>
>
>
>
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>
> <LSA Europa Flight Test Final.pdf>
> <Vortex Generators for STOL-LSA Mod Version 1.pdf>
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