Dick,

I think that winglets would improve roll stability, and L/D, climb
performance and high alt. performance.

Jan Carlsson

www.jcpropellerdesign.com


"Dick" skrev i meddelandet
m...
Thanks for everyones input.

Our group was discussing flying in VFR only (no IMC or IFR) and wing
leveler
only with respect to roll sensitivity of lightly wing loaded, short wing
spanned experimentals.

Trying to make summer flying in chop somewhat easier. We didn't plan on
turning over controls to the device and would still keep a light grip on
the
stick; just wouldn't have to constantly play the stick.

Although we had the impression that a heavier plane would be more stable
in
chop and require less than continual input by stick, that wasn't much of
an
option G.

Although not discussed among us, I wonder if
an increased dihedral result is possible without actually increasing it
physically..

Still would appreciate a little discussion that I can pass on for the next
non-flying day.

Thanks, Dick


"Morgans" wrote in message
...

"Montblack" wrote

Automotive world is using electronic stability-control (ESC) systems
with
documented success.

I'm guessing some variant of this is what you'll eventually cobble
together
in your garage.

More than likely, they are using piezzo electric rate sensors for the
direction information. They are relatively cheap, and do well at
sensing
rapid changes. They have been used for a while in the RC airplane
world,
as
a stability aid, with good success, also. Any really stable electronic
gyro
system in the commercial auto-pilots world, are much more expensive, and
as
far as I know, not available to the public.

Problem is, piezzo sensors have a fairly fast "drift." which makes the
leveling ability good only for a few seconds. If you handed over
control
to
one of these units, within 30 seconds, you would be upside down, and the
unit would think everything is still OK.

In the RC world, if the plane makes a sudden move to go upside down, it
senses the sudden move and if the sticks have not commanded the sudden
move,
it will move the control surfaces to stay right side up. It counts on
you
keeping it somewhat upright, and recalibrates itself often - based on
your
MarkII eyeballs telling the plane to fly level.

Same thing with the car unit in the links. It knows that you are going
straight, or following curves. (still reasonably slow changes compared
to
sudden loss of control) It continually reminds itself that it is going
straight, and re-sets itself. Only when a real sudden move is made,
does
it
correctly sense that it is not going straight and the steering wheel
wants
the car to go straight. The computer then makes corrections to keep the
car
straight.

If a plane wing leveler were based only on these units, and the plane
started banking very slowly, the sensor would not realize it. That is
the
drift. It would re-set as level, then the plane banks another slow
degree,
and the unit re-sets, and the plane banks...you get the picture.

I believe the concoction that had some success, was a GPS wingtip
differential altitude sensor. It used these rate sensors in unison to
help
backup the control movements and make the controls smooth. The units
re-set using the GPS info as the reality of what was level. You have to
use
something (MarkII eyeballs or GPS) doing this.

Good luck to the OP, figuring out a homemade wing leveler. It is a
tough
problem.
--
Jim in NC