There have been many similar devices including the Futaba PA-1, PA-2, The old israli built BTA (Perhaps BTE my memory is short) The FMA auto pilot and the product included with the full Nexstar package. They all use various pitch/roll sensing methods. Some are single axis (roll) and some include pitch axis as well such as the BTE and perhaps the FMA that one I am not familiar with.

I beleve none of them use a special Rx. Also I think you will find all of them while they do work will require many flights by a skilled pilot to fine tune the gains for the desired effect and in almost every case when they are being used as a skills crutch this does not happen and the devices become a severe liability to the airplanes survival.

As for the argument that airplanes with dihedral is just he same thing. Not true, aerodynamic stability acheved by dihedral (roll) and hugh oversize stabilizers and creative decaledge (pitch) provide a totally 'passive' form of stability. Not so with the gimmicks which provide only 'active' stability with control imput.

This fighting of controls is totally counter productive for any student and defeats any real abiliy to aquire flying skills. Its a dead end gimmick in any flight training application.

There is however one application where they are of some use and that is true cross counry flying via chase car and the reason I experimented with the old BTE and PA-1.

John