Removing Pitching from Tri-copter

Hi. I am working with a Tri-copter UAV with a tilting front mechanism and two rotors connected to the mechanism.

I am trying to research on a flight transition corridor of this UAV, which i require to tilt the front mechanism to obtain forward flight speeds.

Is it possible to program the UAV such that there is no pitching inputs on the UAV, however the tilting mechanism allows the UAV to fly forward.

I removed the pitching inputs using my Flight Controller Futaba T8J and flew it using ALTHOLD mode, the UAV loses altitude as tilting occurs.

Is there any better way around it?

Thank you.