how to reduce weathervaning?

[Bob Chiang]

Hi all,

I am building an aerial photo plane and have only recently recognized the problem of weathervaning. I am currently flying AP with a Slow Stick that is susceptible to weather vaning. Depending on the wind direction with respect to the photo subject, it can be hard to orient the camera towards the subject.

I've already built the new fuselage as a tractor with high wing. Since I want to be able to fly relatively slowly I'm planning a low wing loading. Since I want it to be stable, I'm building a polyhedral wing with rudder control. It seems these characteristics will both make it susceptible to weather vaning.

Are there other characteristics that will help? Smaller vertical tail? More side area ahead of the CG?

Is weathervaning one of the reasons to build a pusher with pod fuselage and twin boom tail?

Thanks in advance,
-Bob

[Sparky Paul]

Here's the basics..
http://avstop.com/AC/FlightTraingHandbook/DriftandGroundTrackControl.html
Getting the fuselage (camera) aligned with the desired ground track requires add ing controls to offset the drift.
Usually this means aileron AND rudder.

[BMatthews]

Hi all,
....Are there other characteristics that will help? Smaller vertical tail? More side area ahead of the CG?

Is weathervaning one of the reasons to build a pusher with pod fuselage and twin boom tail?

Thanks in advance,
-Bob

I think Paul has your answer. There's no such thing as weathervaning in a free flying model. I think you're just seeing the ground track drift effect and calling it weathervaning. And the configuration of the model won't change that.

If you're shooting stills just rotate and crop to striaghten them up. If you're doing video then it's going to be harder to adjust for the various wind conditions.

[raptor22]

If you make the plane faster, then it will need less crab angle to offset the drift.

[Sparky Paul]

Here's the problem...
Flying directly into the wind, with the target area not on that heading..
Flying the heading in a crosswind,
and how to compensate for the crosswind..

[hihptsi]

sparky you nailed it i would have to agree to properly control an aircraft with wind you need aleirons and rudders.you then do crabbing as sparky describes,if wind is coming off your right wing bank right slightly to push back into the wind to and compensate by kicking the Tail out the opposite direction with the rudder to the left you will then be flying where you need to and should have no problem in wind,us full scale guys do this Regularly to make cross wind landings pleasent :)

[Bob Chiang]

Thanks for the comments and explanations.

For aerial photography, I often fly at distances where it's difficult to tell if the wings are level. That's why I am building a polyhedral wing. In order to use ailerons to hold the plane level, and rudder to orient the camera, do people use some kind of gyro to control bank? Can it be turned off in flight so you're not stuck with flat skidding turns?

Has anybody experimented with pendulum control recently? ;)
-Bob
(showing my age)