How to Control a Rogallo-Winged Craft?

[FlyingW]

I want to build a Rogallo-winged plane with electric power.

I have seen two types: One had a regular type of fuselage with rudder and elevator fixed beneath the wing.

The other had a motor and landing gear suspended beneath the wing; servos tilted the assembly presumably to shift the weight to make turns.

In the tilting version, would the equivalent of elevator, or up and down be achived by tilting the fuse back and forth?

Please advise. Thanks,

Paul

[BMatthews]

If the rogallo wing is mounted higher than the true 3 dimensional CG then simply angling the wing up and down will be the same as shifting the CG back and forth and make it climb and dive much like a hang glider. Turning could probably be accomplished by leaving the center spine alone and pulling down on the spine on one side and letting up on the other to effectively tilt the wing and again simulate the CG moving from side to side much like a hang glider pilot does.

[fhhuber506771]

Yes, up elevator would be pushing the nose of the wing away from the weight the wing is "supporting." What you are doing is controling the aircraft by shifting CG. If the plane is in stable level flight and you move the CG back the nose will go up. move the weight to a side, and the aircraft turns to that side.

[Sparky Paul]

Due to the difficulty of pushing and pulling, the way hang-glider pilots control pitch on their machines, I suspect the powered versions don't have a pitch control at all, other than powering up or down to climb/descend.
Even on those things, power makes you go up or down.

[fhhuber506771]

depends on the model. I have seen 4 channel 1/6 scale ultralights based on the Ragallo wing, with 2 servos mounted inside a "GI Joe" for scale CG shift control...

[Julez]

Hi!

I control mine with rudder and elevator. Is somehow more precise than the CG technique and better for Aerobatics :D

http://www.sielnet.de/~sn0121/sonstiges/postings/superskyflex/

[FlyingW]

Rogallo Flyers,

It is going to be rudder and elevator on mine. Shown up side down in the picture.

Thanks,

Paul

[Sparky Paul]

You'll be a lot happier with those aerodynamic controls. :)

[FlyingW]

Gents,

I flew her succesfully this afternoon. One charateristic she had was that she would get into these modes where the wings would flutter and she would pitch down and lose altitude. To recover, I added up elevator until the wings filled and she climbed again.

Nose heavy maybe? More positive incidence maybe?

May I have your opinions please. Thanks,

Paul

[Sparky Paul]

The flight envelope will be quite restricted relative to a conventional plane.
Too much speed or too little speed can do what you noticed.
ISTR the sail flutter is termed "Luffing" in the hang-glider community.
Similar to a sailboat that loses the wind when trying to sail too close to the wind. The sail stalls and flutters. The cure is turn away a bit from that direction to get the sail full again.

[kirkpul]

10 degrees incidence is pretty standard for rogallos.

Given you have lots of downthrust, you should be able to get a good cg by suspending your plane with your hands from the cross spars. A good cg will be where, with 10 degrees incidence, your boom will be horizontal or a little bit nose down.

[JRuggiero]

FlyingW,

The Gymallo series of Rogallo-wing airplanes have conventional elevator and rudder sized about what you have on your model. Having flown three Gymallos, I found the controls make for easy flying. Clumsy pilot though I am, I have yet to experience the sail collapse that you and others describe, even with lots of pitch up.

Jim R

[FlyingW]

Jim et al,

I flew her again a few times and have some new experiences:

I found that when I throttled back and let her slow down and glide more she was less susceptible to wing flutter.

On one landing (I need to hand launch and then catch her because of my constrained flying site), I missed and she hit a tree and then fell a few feet to the ground. The front of the fuselage broke behind the motor mount. An easy fix, and while doing it I took the opportunity to add some down thrust (I had none in the original configuration). This helped smoothen things out a bit with the power on.

In general she can fly very slowly and seems less knocked around by turbulence than conventional planes of similar size and weight.

Paul

[kirkpul]

Congratulations, and thanks for the flight report.

Agree, not being knocked around as much by turbulence as most other planes is a major plus for rogallo wing planes.

Used to fly with about 5-10 degrees downtilt in boom and neutral or slight down thrust. Flew well, quite stable including under wot, but wanted to loop inside and outside more easily and climb on less throttle.

So, changed to about 4 degrees upthrust and a tiny maybe 1 degree downtilt in boom when suspended by cross spars.

Result - loops inside pretty easily, helped by the upthrust and little to no boom downtilt...outside loops happen, especially if under no throttle, by going down, then up to stall then hold full down...the down then up then down is to get some momentum for outside loops.

Configured this way, on 3s 1200 li ion, axi 2212/34, gws dd 1280, this 18 oz. auw arrow boom rogallo with 3', 4 equal size spars sail climbs on 40% throttle or less...more throttle requires down elev to prevent soar stall.

[praymond]

Hey sounds like my mini kite plane. on a 3c battery it dosen't loop. it pivots arounf the center spar-- scarry but haven't broken the wing yet! Also have a 30" larger one with a class 400 bl on it Like this design, lots of fun slow or fast.