Easyglider - flaps vs rudder

[Tim Crow]

I have a standard Easyglider4 and wondered if it would be more useful to have flaps rather than the rudder. I believe it would be easy enough to cut in-board flaps and use the rudder servo to operate them via cable/rods exiting through the fuselage sides. I'd fix the rudder and just fly aileron/elevator - on other large models with full house I rarely touch the rudder anyway, relying on differential ailerons throw to damp out the adverse yaw. Any thoughts? Would sink rate be improved by small amounts of flap when thermalling?

[Ron Gray]

You can apply small amounts of aileron to do the same thing, at least that’s what F3K do (no flaps).

[John T]

Hi Tim,

I don't have an Easyglider, but I've had a Radian Pro for a few years and that definitely thermals better with about 7 degrees of flap. However, I do find a touch of rudder as well as aileron starts a turn more smoothly.

[MattyB]

I don't think you will gain much with flaps on an EG4 to be honest - the section is not really dsigned to benefit from them. You might lose more through not being able to balance your thermal turns with rudder. If you are going to try them I would say keep the rudder - the increase in weight won't be hugely impactful on a model like this, and it will mean you don't have any adverse yaw issues.

Edited February 16, 2021 by MattyB

[Frank Skilbeck]

I agree with Matty, having an Easy Glider Pro, I don't think flaps will make any appreciable difference. Also setting up flaps to operate off the "rudder" servo in the fuselage would make rigging a pain and having flap servos in the wings would be a simpler option IMHO.

[leccyflyer]

I find when flat field flying with my Easyglider I use the rudder far more to make flat gentle turns than I would ever use flaps. I can't envisage a situation where I'd be prepared to lose my rudder for the sake of adding flaps.

[Jonathan M]

I'd leave the rudder well alone.  To do it properly you'd need a servo for each flap anyway, so they can be co-ordinated to work with the ailerons for smoother, lower-drag turns etc.

If you really want, you could always experiment with flight-modes to give you variable-camber just on the existing ailerons.  If that doesn't make enough difference, you could then extend each aileron closer towards the wing-roots (i.e. cut and hinge the foam and join to the existing aileron roots), thus approximating more closely to the almost full-span flaperons of a F3K.  You might only need a mm or two down to notice a real difference:  a three-way flight-mode switch would give you three positions: flush for 'normal', a bit down for 'slow-cruise' and a bit more down for 'thermal' (or use a slider for infinite variability), and you'd most likely then need individual elevator trims for each mode.

Even if you didn't change anything (which I personally wouldn't on a stock foamie like this), you'd benefit from teaching yourself to use the rudder for flatter turns in thermals (especially when lower down and scratching about for whatever rising air there might be!), using opposite-aileron (or opposite-flaperon as the case may be) to help balance out any rolling-tendency to keep the wings as level as possible to maximise the upward component of lift.

Edited February 16, 2021 by Jonathan M

[Tim Crow]

All good thoughts; I'll take the simple option first of mixing a rotary switch channel to give a touch of up ailerons when the strong spring thermals make getting down hard, and a touch of down ailerons when the forecast strong thermals don't materialise. I'm conscious down ailerons will promote tip stalls, so flaps would be better and also mìght be good for short landings but I agree it's probably not worth the complication on this model as my field is a decent size.

Edited February 17, 2021 by Tim Crow
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