Crow braking with a DX8

[David Holland 2]

Good afternoon, gents. Tried slope soaring for the first time of the Great Orme last weekend and loved it. Flew a Max Thrust Lightning and a Wildthing, both were great fun and the Wildthing was really easy to land as it seems almost indestructible and could be "dumped" with impunity. The Lightning, however, was a bit more tricky and a lot less robust. At the moment the ailerons are on a Y-lead but I could easily put the two servos on seperate channels and, if I could figure how to do it, have both ailerons raise on approach to slow it down a bit. Can anyone help with the Tx programming to acheive this?

Thanks in advance, David

[Denis Watkins]

Look through these David, it is the same for most Tx

**LINK**

[Shaun Walsh]

I set up crow and camber on a BFG 1600 using a DX6 by following this video.

https://www.youtube.com/watch?v=Rzqqou9PjVQ

[Shaun Walsh]

Just checked and it looks like the Lightning doesn't have flaps so you won't be able to use a crow set up but can, as you said, use the ailerons as spoilerons.

[David Holland 2]

Thanks for the info, fellas, never thought to see if the question had been asked on the forum before. Shaun, you are correct, no flaps hence the spoileron/flaperon route. Got it set up now. One final thought, are upwardly deflected ailerons more effective at dumping lift than downward at increasing drag?

David

[PatMc]

David, spoilerons don't actually allow the model to slow down more than they would if not used, in fact they increase the stalling speed. However they do increase the descent rate and angle making it easier to land in a tight area. They also make the aileron function less effective, I always program for coupled ail + aprox 50% rudder (CAR) to switched in for the landing phase when I use them.

[Frank Skilbeck]

Not on Pats comment re aileron effectiveness, if you are normally flying with aileron differential then, if your Tx supports it, you should bring in aileron differential suppression as spoilers are deployed, this means that when both ailerons are raised the down going aileron has more travel than normal, restoring aileron function.

[PatMc]

Frank, IMO ail diff suppression only partialy restores aileron function, CAR is generally more effective. On a small aerobatic glider like the MT Lightning I wouldn't use ail diff anyway, it achieves little & slows the roll rate.

[David Holland 2]

Cor, I'm getting good at these mixes, l've now got 50% rudder programmed in with spoilerons deployed, thanks for the tip. I did think aileron effectiveness looked a bit compromised. My instinct is that I might need some up elevator mixed in with spoileron, what do you think? Thanks for the help,

David

[Steve Colman]

Posted by David Holland 2 on 01/10/2018 10:06:17:

My instinct is that I might need some up elevator mixed in with spoileron, what do you think? Thanks for the help,

David

Logical as it may seem David, it might not be so. When I activate spoilerons on my Solius down elevator needs to be mixed in. Do some tests up high before committing any landings.

[PatMc]

My experience has been the same as Steve's, on very model I've used spoilerons (without coupled flaps) the nose has risen as the spoilerons have been deployed. The good thing about this is that if the model is going to land short when they're deployed you still maintain flying speed if the ailerons are dropped back to normal in order to stretch the glide.

Edited By PatMc on 01/10/2018 11:26:12