Hi Bud=2C
Thanks for your input again. It will be interesting to see what Europa will
come up with. I especially like your attachments.At the moment I am still
learning to fly this thing properly=2C and approach/landing without any air
brake. I am getting very close to the adjacent cornfield=2C then the fence
=2C and I am still touching down way too far down the runway. When a goarou
nd is called for=2C I just open the throttle a little bit and I am off agai
n. No flaps=2C prop or trim to worry about.I don't really have the official
approval (Special CofA) yet to fly the motorglider=2C but hope to get it s
oon.On the airbrake issue=2C I am going to start with putting in a couple o
f holes in each airbrake=2C drilled horizontally in the max open position
=2C and re-enforced with a ring of flox.As you said=2C in the worst case it
is easy to fill them in again or put tape over it.
Karl
From: budyerly@msn.com
Subject: Re: Europa-List: MG Airbrake question
Date: Sat=2C 28 Aug 2010 20:48:51 -0400
Karl=2C
I normally get 57 degrees and can tweak 60 but usually don't bother for the
last 3 degrees.
See the notes from my shop instructions attached.
I have not minded the pull effort=2C as they stay at 50% for landing
normally. Above 85 knots it is a heck of a pull past 50%. John
Bolyard and I have discussed putting holes in his airbrake trailing edge to
decrease the deployment effort (as in the Dauntless) or lengthening the
leading edge and fitting holes to prevent rapid pressure build up or they w
ill
flop wildly open. Unfortunately it will be manual research and trial
and error on my part until the factory planes are finished and
tested... NASA=2C or NACA more accurately=2C and the Air Ministry documents
(see one example above in .pdf) are far and few between on air brake
analysis as dive or airbrake research was proprietary data of manufacturers
who
used hydraulics to move their airbrake. Our airbrake is a copy of a
Slingsby design which was quite successful=2C but something went wrong in t
he
translation.
Just a note to the others=2C the MG wings (about 34 sets) were sold only by
the original company to the US/North American market ( I think the last set
was produced in 2004) but unable to be flown in Europe until
recently. Today=2C Europa is ready to begin new MG
wing production certified under JAR-VLA and CS 22 requirements which make
them stronger and saleable world wide. It took Dave Stanbridge to make
this happen. Now the factory has two MGs being constructed and will be
evaluated for these kind of fixes. First a computerized aerodynamic
evaluation was made=2C followed by a detailed structural test=2C currently
the rigging and building is being evaluated=2C which will be followed by
flight test and airbrake fixes will surely follow.
Doesn't help your situation now I'm afraid. The airbrakes are not
dangerous as is but are very inconvenient to use without pumping up the
muscles. You can tell a MG pilot by the size of his right bicep.
I know we all are going as fast as time and money permit.
Bud
----- Original Message -----
From: Karl Heindl
To: europa-list@matronics.com
Sent: Saturday=2C August 28=2C 2010 6:50
PM
Subject: Europa-List: MG Airbrake
question
Hi motorglider guys.
Has anyone made any changes to their airbrakes ? I find they requires a
lot of force to hold them in the fully open position. The air pressure on
the
bottom half far exceeds that on the top.
Because of that it is also impossible to get the maximum deflection of 60
degrees. I mounted an angle indicator=2C and it shows about 45-50=2C whic
h
severely degrades their performance.
I don't understand why nothing was ever done about this. They have been
producing these wings for about 11 years now.
The obvious solution to me is to reduce the area of the bottom half=2C
either by putting in holes=2C or trimming back the trailing edge.
These brakes are not really necessary with the engine running=2C but are
essential when I get to making dead stick landings.
Karl
href="http://www.matronics.com/Navigator?Europa-List";>http://www.matronhr
ef="http://forums.matronics.com";>http://forums.matronics.com
href="http://www.matronics.com/contribution";>http://www.matronics.com/c
|