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------ Start of attached email. Subject: Flaperons in reflex position ------
Hi all
I would appreciate any ( real world ) input from any of the flying rebels as
to the increase in cruise performance & top speed they are getting with the
flaperons set in the 5deg. reflex position from the 0 deg. position. I built
my rebel with fixed ailerons and flaps. ( flaps go from 0 to 40 deg. with the
flap handle on the floor between the seats ) I have 70 hours on the plane and
have been very happy with it's handling however if there is enough increase
in performance it would be fairly easy to incorporate the reflex position
into the system.

Secondly, has anyone done any experimenting or installed a simple speed
fairing over the tail spring and lower tail strut attach fitting. I have
streamlined the lift struts but the rest of this area looks like it creates a
lot of drag.

Steve Sloan 536R




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------ End of attached email ------

Hi Steve !

With 10 years of Rebel flying, in many different configurations
and engines, I can tell you that the reflex IS worth the effort.

I've found that one notch of reflex (6 degrees), gives about a
3 mph increase in cruise, and, if you have more than about 120 hp.,
a SECOND notch, giving 12 degrees, will add ANOTHER 3 mph !

The other big advantage of using negative flapperon is that it
gets rid of the excess lift at high speeds (the speed increase comes
from reducing the drag caused by the excess lift) which has a VERY
NICE side benefit - it makes the Rebel even more stable !! It reduces
any tendency to want to bounce around in turbulence, making it ride
like a much larger aircraft !!

I'm TERRIFIED to hear that you are using 40 degrees of flap !!
The Rebel was designed and tested for a maximum of 18 degrees !!!
There is a very real possibility of you tearing something off !!!!!!
Please check this out with the factory !

Don't know of anyone fairing the tailwheel - this was popular
in the 1920's & 30's, and might help a bit. The biggest single drag
reduction comes from cleaning up the landing gear - there's 10 mph
to be had by putting streamlined fairings on the bungee & top inside
gear legs, if it's done right. Another biggie that many folks miss
is to put a top fairing on the gap between aileron sections - there
is a tremendous vortex coming out of that gap !! Just a piece of
.020 or .025 aluminum will do the trick, but make sure it goes
well forward to wrap the leading edge of the aileron, and is
well secured with screws. It is almost impossible to fair the
bottom of this gap neatly, because of the hinge position - if you
just add a cover, you'll create a pocket (good for lots of drag !).

I suppose it might be worth trying streamlined fairings for
the tail struts. FWIW, 1/16" Lexan can be bent cold in a brake to
make very nice fairings. It's much easier to work than aluminum,
won't crack, and you can see through it to inspect the surface.
Apparently, it can be painted easily, too.

.....bobp

------------------------------orig.-------------------------------------------
At 07:14 PM 10/13/00 EDT, you wrote:

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Date: Fri, 13 Oct 2000 19:09:50 EDT
Subject: Flaperons in reflex position
To: Murphy-rebel@dscol.com
MIME-Version: 1.0
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Hi all
I would appreciate any ( real world ) input from any of the flying rebels as
to the increase in cruise performance & top speed they are getting with the
flaperons set in the 5deg. reflex position from the 0 deg. position. I built
my rebel with fixed ailerons and flaps. ( flaps go from 0 to 40 deg. with the
flap handle on the floor between the seats ) I have 70 hours on the plane and
have been very happy with it's handling however if there is enough increase
in performance it would be fairly easy to incorporate the reflex position
into the system.

Secondly, has anyone done any experimenting or installed a simple speed
fairing over the tail spring and lower tail strut attach fitting. I have
streamlined the lift struts but the rest of this area looks like it creates a
lot of drag.

Steve Sloan 536R

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Your following message has been delivered to the 163 members of
the list murphy-rebel@dcsol.com at 21:13:21 on 13 Oct 2000.
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That was my first reaction too!!!! SO I went out to the hanger and measured
my personal Rebels Flaperon deflection. With my flaperons fully down
(cheating at 24 degrees for a little extra stol performance!) and full left
(or right stick) the flaperons actually do go down a full 40 degrees. That
is of course if you are strong enough to pull full left or right stick in
flight, when the flaperons are down full! I find the only way to actually
steer with the flaperons down full is to use the rudder!

As for the reflex position, it definitely does increase the cruise speed and
cut some lift (drag) so you don't get tossed around as much on turbulent
days! I do find that the aircraft does lose some longitudinal stability
though, when flying in the reflex position, and that took a little time to
get use to.

Regards,
Wayne G. O'Shea
www.irishfield.on.ca

----- Original Message -----
From: "Bob Patterson" <bob.patterson@canrem.com>
To: "Murphy Rebel Builders List" <murphy-rebel@dcsol.com>
Sent: Friday, October 13, 2000 7:52 PM
Subject: Re: Fwd: Flaperons in reflex position

I'm TERRIFIED to hear that you are using 40 degrees of flap !!
The Rebel was designed and tested for a maximum of 18 degrees !!!
There is a very real possibility of you tearing something off !!!!!!
Please check this out with the factory !

*-----------------------------------------------------------------------------------*
The Murphy Rebel Builders List is for the discussion
between builders and owners of Murphy Rebel aircraft.
Archives located at:
http://www.dcsol.com/murphy-rebel/lists/default.htm
*-----------------------------------------------------------------------------------*




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