Crab, old boy stay in low alt! Which radar altimeter will have a accuracy of 50ft in 2000ft? The most i know have just at least an indication in such altitudes in 50ft steps, plus technical tolerance. And your heading hold is nuts. In 20 minutes i fly easy 5-10 miles groundtrack allways horizontal any time with fixed heading.
And a DGPS will give a much more correct altitude than a normal GPS.
