Hello everyone,I

Hi,Never tried, but maybe you can add somewhere the pressure diff. in feet to one of the altimeters.I think 1 mbar is about 10 feet.So make a L:Var:1013.25 (A:ambient pressure,mbar) - 10 * (>L:alt diff,number)For the altimeter add:(A:Indicated Altitude,feet) (L:alt diff,number) +So there will be a difference in indication between the 2 altimeters.For your special case i think you can work it out.Hope it helps,Jan"Beatus Ille Procul Negotiis"

Correction,Instead of ambient- use sea level pressure; just tried and it works.Jan"Beatus Ille Procul Negotiis"

Hi,Thanks for the reply. The linear approximation for the pressure lapse rate only works for low altitudes, but I may still be able to use this method after making it properly (and probably unnecessarily) complicated.Lee B.