Just thought of this the other day- don't know if it's been done, or really even how to implement it.

Basically- in the tail of the plane, parallel with the wing, install a small reversible ducted fan. Make it work with the rudder servo. Think this could open up a bunch of 3d maneuvers? Or if not, how about in combination with reversing the main motor driving the prop, only at low speeds of course...

about 10 years ago MAN had some pics of a fun-fly plane with a heli tail-rotor back on the boom. it was driven by the rear starter shaft of the .32 heli engine used on the nose of the plane.
IIRC it did not replace the tail but was used along with it.


dave

This idea has possibities, I think. I looked into putting servo-controlled vanes in the extreme end of a ducted fan model's air jet. Ducted fan models seldom have enough excess thrust for good 3D stuff, but most turbine powered jobs do, but they would need stainless steel or titanium vanes. Also looked into using an articulated rudder with two hinge lines, that can deflect 90 degrees for prop planes, but the servo torque requirement is a killer. On an experimental biplane model, I tried large rudders, slaved to the normal rudder control, at the rear of covered cabane struts with good results - incredibly tight knife edge loops and generally wild knife edge cavorting. Go for it.

The ducted fan might be an option what with the availability of powerfull and small motors and light battery packs. I see this built into the fuselage back with the tail. It would only need a few ounces of thrust to have a wild effect. The radio could be run off the BEC part of the ESC. And you'd have to find a boat or car ESC with polarity reversal. Either that or duct a heli tail rotor in there, run the motor full out all the time and control the pitch with a spare servo.

If you simply add more lateral area up front on the model- you can get knife edge flips . no gadgets req'd . Honest.
On my blue foam Spitball - it will do a knife edge flip in roughly a 5 ft dia circle. ( well sorta a circle -)
it actually appears to be in a couple of feet but that isn't possible.
The profile models with lots of lateral area- properly laid out ,are simply amazing in the pitch flailing stuff
also they snap roll with a vengance in any attitude / speed.- something the long tailed stuff does not usually do .