I recently bought a used E-Flite F4F Wildcat - what a great plane. One of my first foamies. I took out the Spectrum safe equipped receiver and installed a Radiomaster without any stabilization. Now when I turn it on the rudder servo and the aileron servos are way out of adjustment (almost every time) and I have to check them every time. So is it all three servos that just aren't centering and I need to replace them or??