"Roy Smith" wrote in message
...
"Gary L. Drescher" wrote:
A hundredth-degree change in descent angle is
(barely) perceptible on the ASI or VSI.

I'd like to see a pilot or VSI which can notice the difference between
500 fpm and 502 fpm.

You're right, it would have been more accurate for me to say a *few*
hundredths of a degree. But that still justifies more than one decimal
place of precision. A few hundredths of a degree change of descent angle
moves the VSI needle almost as much as a one-degree heading change moves the
HI (and courses are routinely specified with single-degree precision).

--Gary