|John Bisset||09/07/2020 22:57:24|
|226 forum posts|
One of my 'bought not built' models is an ST Salto. A super wee flier that climbs well and aerobats nicely - or would if I was a better pilot.
Landings however are really long flat affairs. The machine is so low drag that I have to approach really low. Two questions -
Has anyone modified one of these to add more drag? I wondered about trailing edge airbrakes, if I could find space in the cockpit fpr another servo.
Is it worth trying to sideslip to add drag. I have never tried that in a model, though it works well in the fullsize - or at least in the Libelle which has fairly poor airbrakes and is quite similar to the Salto. I am not sure I can balance aileron with rudder well enough in a model.
|Anthony Scott 2||09/07/2020 23:41:13|
|102 forum posts|
If you are using separate channels for each aileron try selecting "flaperon" & raise both ailerons approx 50%. Otherwise, side slipping it is!
|Richard Clark 2||10/07/2020 08:13:23|
|418 forum posts|
I agree with Anthony.
My old Multiplex Graffiti had the same problem. but when I set it up with 'flaperons' it came down at about a 45 degree angle . Though the fuselage was more or less horizontal.
A few points:
Don't set them, 'up' too much I suggest about 5mm to start with. You can always increase it. Check that with them up and the ailerons moved fully left and right you don't strain the hinges.
Make sure it's the same both sides. It probably will if the ailerons move evenly already.
You don't need them on a slider, a switch will do.
You might need to mix in a little up elevator when they go up.
TAKE CARE. Try the effect high up at the beginning.
Sideslips as an alternative.
All fine in theory but with a model it's difficult as it's very much a 'seat of the pants' affair to get it right and you don't have that with a model.
|John Lee||10/07/2020 09:29:48|
|764 forum posts|
I'm afraid these suggestions are not viable as this model has a single aileron servo pre-mounted in the fuselage and to add a second is pretty much impossible with the push rod geometry & lack of space.
I've added a separate control so that I can pop up the EDF pod without operating the motor to give some extra drag on the approach. It helps a bit but it's still a pretty flat glide.
|Denis Watkins||10/07/2020 10:11:51|
|4536 forum posts|
There are a few models like this John, that carry on past you if they can.
Let us talk about landing from the left, uniform, practiced, similar pattern, everytime.
The landing starts directly in front of you, model moving down wind to the left, just above eye height, not bending head back.
Evertime, parallel to the runway, in front of you straight and level with no gain in height.
With practice, using the throttle, I/C or electric, maintaining level flight in front of you travelling downwind
Now, loose height in the turn
Fly 2 corners of its easier, loosing height naturally in the turn, to the next turn towards you.
Maintain some power and adjust the throttle that the model maintains distance from the ground
Then, bring down the power that the glide is a gentle slow loss of height to the ground in front of you
Rehearse this in your head, then complete everytime.
Your aim is to have a landing sequence though each one is different due to wind speed and direction, you alter
|John Bisset||10/07/2020 12:47:16|
|226 forum posts|
Than ks John Lee, that is what I thought. The power pod does add a wee bit of drag - must look more deeply into my (Spektrum DX6) radio to set up a control for pop up, no power.
Thank you Dennis, very kind & useful. That is not far from what I normally aim for. With varying success, no crashes so far, touch wood.
I have to say that losing height in the turn when starting at 'just above eye height' only works readily for me if conditions are benign. Rather fraught otherwise. My normal flying site tends to have turbulence off trees and hangars, to add excitement. My personal preference is for a glide approach, hence some means of increasing drag would be handy. I admit that does come also from full size habit - I have never liked dragging in under power. (I also tend to default to the continuous curving turn to finals, again from full size practice. That picture sits well in ,y mind)
Also laziness, - good airbrakes or draggy flaps make landings easier and more fun. I do like to slow landings for a proper flare. Long flat low drag stuff doesn't look neat to me!
Not relevant to the Salto of course, but is 'crow braking' the use of both aileron and flaps simultaneously - ailerons both up and flaps down? I am intrigued at suggestions of the both ailerons up option for other sailplanes- presumably that needs some loads trimmed out at the tail ?
Edited By John Bisset on 10/07/2020 12:47:36
Edited By John Bisset on 10/07/2020 12:48:31
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