Steve Willner replied to Bill Owen:
>> The angle is correctly termed "altitude", and the distance
>> above sea level is the "elevation".
>> I suspect that "elevation" came to be used for the angle
>> in much the same way that "range" supplanted "distance" or
>> "prograde" supplanted "direct" -- the original aerospace
>> engineers of the 1950s weren't familiar with existing
>> astronomical terminology and invented their own.
> I'm wondering whether the military uses the opposite
> convention. The height an airplane flys at is "altitude"
> (distance), while artillery aiming uses "elevation" (angle)
> in some sources I've seen. Any artillery vets reading this?
I have no direct experience with any of this, but I've
*always* heard and read the term "elevation" used for
angle above the horizontal in artillery and surveying.
Similarly for the term "range" in artillery.
Consider an air traffic controller looking at a radar
display which gets its information about the altitude
of an aircraft from the elevation of the radar antenna.
(I think they don't work that way anymore, but they did
in the 1950s: A horzontally-scanning antenna for range
and a vertically-scanning antenna for elevation.)
-- Jeff, in Minneapolis