S-tec 55x Installation Manual -

Final tuning must be done in the air. This involves setting the levels to ensure the aircraft doesn't "hunt" (oscillate) during altitude hold or navigation tracking.

Check for the programmer/computer, pitch and roll servos, and pressure transducer. S-tec 55x Installation Manual

Confirm you can manually overpower the servos with reasonable force. Final tuning must be done in the air

The programmer/computer is designed for a standard 6.25-inch radio rack. Position within easy reach of the pilot. pitch and roll servos

If you are integrating it with (like Garmin G5 or GI 275).

Use the correct tension specified in the S-TEC airframe-specific kit.