Pete,
No noticeable difference other than you can look out and see the dirt flowi
ng with the water making a nice visual display of the laminar to turbulent
transition layer. The plane does slow down but in heavier rain, comes heav
ier turbulence so I normally slow down as we get vertical development in ou
r rain showers.
The problem with the XS is it is excessively heavy because it is extremely
easy to add more stuff.
Best Regards,
Bud Yerly
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s 10
________________________________
From: owner-europa-list-server@matronics.com <owner-europa-list-server@matr
onics.com> on behalf of Pete <peterz@zutrasoft.com>
Sent: Wednesday, August 14, 2019 9:44:17 PM
Subject: Re: Europa-List: Re: of interest
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<mailto:budyerly@ms
n.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 te
mplate and of course a good eye. Technique on rolling the leading edge by
rolling off the edge at a 45 gives a uniform leading edge. The XS is out o
f the mold pretty good. Though I=92ve seen wings built on saw horses that
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. Spea
ks 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. S
ee 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 molec
ule that is pretending to be a naughty teenager looking to get out of work.
If there is a gap to escape work, they will rush to go through it, result
ing in low productivity, and drag. See www.customflightcreations.com<http:
//www.customflightcreations.com> for some of the other building and flying
articles.
Since the Europa wing is very well designed and up to 1450 pounds, has a re
asonable laminar flow and nearly perfect elliptic wing lift distribution, s
o aerodynamic gimmicks like wing fences, winglets, and VGs. I have not fou
nd it necessary to fly with the wings in the raw or just primed and sealed.
The stall of the Europa is slightly less abrupt than a typical series 6 a
irfoil due to excellent leading edge contour. The best stall taming is wit
h the POH recommended stall strips as it adds great pre-stall warning feel
prior to the actual break. You will find modifying the wing shape to impro
ve flow will be an exercise yielding nothing. I=92ve done tuft tests, and
the wing tends to have a nice span wise root to tip stall progression provi
ding the wings are built the same and square of course. The stall of an un
modified wing begins separation at the root, the downwash over the stab dec
reases, the 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 str
ip allows a complete aft stick stall in most aircraft with the stick full b
ack and a gentle nose down rumble and shake. Don=92t let the nose wader as
it will rumble off opposite to the ball. Flaps down depends on the flap r
igging. The rumble begins only just prior to the stall and the nose drops
like any other large flapped conventional tractor aircraft. Adding VGs mad
e for an aircraft with excellent control but it sank like a rock at 40 KTS
with no low speed warning. Like Buzz Lightyear, I was, =93Falling With St
yle=94.
Many pilots have never flown a light aircraft with the center of mass so ne
ar 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
left just at the stall break even at idle power! This results in a left wi
ng drop as one would expect. The stall strips give excellent feel approach
ing 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, an
d smooth, and you will be rewarded.
Get the family into the build, but don=92t be Captain Bligh, let them have
fun and help (well for an hour or two when you need an extra set of hands).
Remember, =93Ain=92t nobody happy unless Momma is happy=94!
Best Regards,
Bud Yerly
Custom Flight Creations, Inc.
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________________________________
From: owner-europa-list-server@matronics.com<mailto:owner-europa-list-serve
r@matronics.com> <owner-europa-list-server@matronics.com<mailto:owner-europ
a-list-server@matronics.com>> on behalf of n7188u <chmgarb@gmail.com<mailto
:chmgarb@gmail.com>>
Sent: Tuesday, August 13, 2019 12:06:26 PM
t@matronics.com<mailto:europa-list@matronics.com>>
Subject: Europa-List: Re: of interest
rb@gmail.com>>
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 b
uilder 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
canard!). But my EZ flies great, very docile and the canard stalls at 58 kn
ts so no complains. yes, it will pitch down in rain (or not take off in rai
n and 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
it would be challenging to ensure the entire span is accurate or do you ch
eck at some discrete span points and then ensure the thing is fairly smooth
in between?
Regards,
Chris.
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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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