Setting up tailerons

[frustratedpilot]

Hi guys,
When setting up tailerons in conjunction with main wing ailerons (e.g. F-14, F-18), do they move in the same direction or in opposite directions to make a turn?
For example, when making a left turn, the port aileron goes up and the starboard down. Does the port taileron go down or up in this turn? Please help, as I've confused myself! :confused:

[JetPlaneFlyer]

They would work in the same direction as the ailerons.
But I wonder; what is the reason for having tailerons AND ailerons :confused: Usually tailerons would be used where no ailerons were fitted (I think). Are you simply after mega fast roll rate?

Steve

[Texas Buzzard]

There may be a need for adding ailerons to a ship that is flying with taileron only. The case would be when the airplane is slow to roll (turn) with tailerons only.

I have one, a 28"w.s. F-22 that was very slow to roll for a turn at first. I think the reason was that the tailerons were located very near the centerline of the ship. Being close to the centerline was good for elevator but in the roll axis the leaverage of the roll input was weak. Hope I 'spained that right.

So it was easy to add true ailerons and connect them to the taileron servos. Now the roll rate is normal. Yes, each taileron moves in the same direction as each aileron moves. Up is up both for each taileron and each aileron. The roll rate was vastly improved. On the very first test flight I was really worried. The ship took 6 to 10 seconds to respond to turn input. Roll was extremely slow without ailerons. Yes the tailerons were too close to the centerline.

[JetPlaneFlyer]

My thought was more "why would you add tailerons to a model that already has ailerons?"
For most models the ailerons will be much more effective (because they are located further outboard) so adding tailerons may really not be of any benefit but it incurs the weight penalty of an extra servo.

Steve

[Brandano]

I think the F14 only uses aileron at minimum sweep, and on the F18 the ailerons are help to the roll, but are much more important as automatic flaps. On the Panavia Tornado there's no ailerons, it will however us spoilers to roll, especially at th minimum sweep. The tailerons on modern fighters are rather large surfaces, that can easily achieve 900 degrees per second rolls on their own. Naturally, that doesn't mean that here's no use for ailerons. They add redundancy, are more efficient in some flight regimes, allow you to adapt the camber of the wing to the plane's attitude... but tailerons+ailerons+canards and such are better left to integrated fly-by-wire jobbies with appositely studied flight control laws.

[frustratedpilot]

Thanks for all the submissions. I am building a Tamecat from plans, but would like to make it slightly less tame!!! :D Thanks again and I'll certainly bear in mind what you've said.

[BMatthews]

The Tamecat has a regular sport trainer planform with a slightly wider than normal fuselage. And it's only slighty wider than a regular sport model. Because of this you'll find that the tailerons won't have any really noticable effect. You'd be far better off to increase the width of the strip ailerons and use more throw.