Originally Posted by
Jan Olieslagers
In which case one pushes the appropriate button on the transponder, and reports what the display shows... Problem solved, indeed.
No.
The altitude encoder transmits a reading based on 1013.2 hpa which is then converted by the radar display on the ground which has the current QNH fed into it and updated when necessary.
Last edited by chevvron; 11th Aug 2018 at 14:37.