REFLECTOR: Aileron Rigging (Reflexing)

[John Dibble]

I think decreasing the main wing lift will cause the main wing to sink 
relative to the canard, increasing the AOA and require the elevator be 
further up to keep flying level.  For my plane that would mean more drag 
since my elevator is up at cruise anyway.

John

On 4/26/2012 10:57 AM, Lawrence Epstein wrote:
> I am not convinced that the concept of reflexed ailerons reducing 
> /total /drag applies to canard aircraft.
>
> Part of the drag reduction is, as previously mentioned, decreasing the 
> AOA of the wing, therefore decreasing lift and therefore drag. The 
> difference is, in a conventional (aft tail/elevators) this would 
> require /less /lift from the elevators (pushing the tail down to 
> compensate for decreased lift) and /decreasing /the drag for the 
> elevator/rear "wing" as well. This is the same reason conventional 
> airplanes fly faster with aft CG.
>
> In a canard aircraft, decreasing the overall lift of the main wing 
> would require deflecting the elevators /down/, thereby /increasing 
> /the lift of the canard and increasing the drag created by the 
> /forward /wing.
>
> I'm not saying that the net wouldn't be less drag, just that it would 
> need to be determined (experimentally or if someone knows how to do 
> the calculations).
>
> Larry Epstein
>
> On Thu, Apr 26, 2012 at 11:40 AM, John Dibble <aminetech at bluefrog.com 
> <mailto:aminetech at bluefrog.com>> wrote:
>
>     Without knowing it, I think I've already done the testing for
>     you.  When I bought my plane the ailerons were 1/4" up.  I flew
>     that way several years with no problems.  However I had nothing to
>     compare with.  Then after the discussion several months ago, I
>     changed mine to 1/16" up.  That resulted in a more sluggish
>     response, but more stable tracking.  I think I picked up a few
>     knots, which is contrary to what your article is saying.  I think
>     Larry Coen's comments that a neutral position (when in flight)
>     will give the least drag is the best explanation.  I see no
>     concerns if you want to experiment  and position the ailerons up. 
>     It's more responsive, which I like .  However I prefer the
>     stability (and greater speed?) more.
>
>     John
>
>     On 4/26/2012 9:58 AM, Ron VelocityXLFG wrote:
>>     http://www.angelfire.com/on/dragonflyaircraft/reflexing.html
>>     <http://www.angelfire.com/on/dragonflyaircraft/reflexing.html>
>>     I know there are people with way more understanding of this than
>>     me . I only entertain the idea
>>     because the web sit speaks of gaining 10- 60 knots in theory .
>>     Reflexing the ailerons
>>     would be a fairly easy  modification .  If you could gain this
>>     kind of speed with the same HP
>>     and set the system up so as to remove the reflex of the ailerons
>>     as the plane slows down why not
>>     give it a try.
>>     Yes deep stall is very possible and maybe the whole reason not
>>     to  do this but what if you could
>>     rig the system to remove the reflex in the system quickly and
>>     would also automatically removed
>>     the reflex  if the plane is under some predetermined speed. With
>>     a gain of 10 knots with the same
>>     HP sounds real enticing.
>>     No I am not trying this just entertaining the idea. I do not own
>>     a Parachute so I will only entertain the idea
>>     for now. Has any one looked into this and would like to share.
>>     Ron
>

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