How many servos?

[thurmma]

Quick question. On a 103" 3DHS Extra 330SC, can I get away with 1 7955TG in the wing for flying IMAC? I am having one heck of a time getting the 2 servos matched and just realized that there is a center slot for a single servo. If I was to run 1 7955tg at 6 volts, would this be enough? I am mainly worried about the possibility of flutter. I know it will have enough torque

 

[Kevin-Young]

I would suggest going with 2 or if you really want to use one servo then upgrade the servo to a version with some more torque. On all of the 35% airplanes we offer we strongly suggest 2 servos.

If you were sport flying the airplane one 7955TG may work but you would probably see a fair amount of blow back on the aileron so when you are flying faster your rolls would act slower. Also on the 3DHS planes they have a built up wing which is generally subject to more flex in the aileron so having 2 servos would help spread the load a lot better and keep things from flexing.

If you are having trouble matching your servos you may want to try something like the Futaba MSA-10 or JR matchbox as they can be great tools in matching servos.

 

[SleepyC]

Also the 3DHS planes notoriously have HUGE ailerons, so 2 will seriously help you out. Those suckers are like barn doors! But MAN do they work in post stall!

 

[thurmma]

They are HUGE there is no doubt about it

 

[bigblueswope]

How about splitting the ailerons?

 

[Jetpainter]

How about splitting the ailerons?

There you go, now that sounds like a great idea. I know Terry and several others swear by it.

I've flown a 35% Pilot Extra 330 SC with one 8711 on each aileron and the blowback was awful. The faster you went the slower it rolled.

 

[thurmma]

How about splitting the ailerons?

Never thought about that. Seems like it would be a bigger nightmare getting both sections to work in unison when you wanted it to work as an aileron and not flaps/ailerons.

 

[Pistolera]

Programming split ailerons is pretty easy. But to split them properly, you'll need to remove them to install endplates on the new edges and also for some additional hinges near the splits.

As for one servo, I ran two (each aileron) 7955TGs on mine (6v) and there was some blowback even then. Regardless of the power of the servo, i'd be more concerned with flex and flutter with just one. The middle slot is for thos who use 3 servos.....Joe Smith and some other ran 3.

 

[Terryscustom]

2 minimum!! IMAC or not that aileron makes up a fair percentage of your wing area......it's not just guiding you through the air it has air pressure lifting your plane the entire time it is up there.

 

[Pistolera]

Yep....that too!