altitude

[maximus]

does a pilot flying an aeroplane at a approx height of 30,000 feet have to regulary adjust the altitude/height to componsate for the shape of the earth... ie; if he hit 30,000 feet and never adjusted his instruments would it gain height because of the earth being round and would it ultimatly shoot off into space?

[Space]

if he stays at the same altitude and doesn't adjust his instruments then he will go around the earth at that altitude.
Why would he go up to space? because he would go in a straight line? Keeping the same altitude doesn't mean going in straight line, especially when you use air pressure to measure altitude

[ajaxyhap]

Of course he doesn't need to keep adjusting the altitude- by using an altimeter the pilot stays 30000 feet above sea level, therefore flying in a continuous arc . How could an altimeter read 30000ft and let the pilot shoot off into space?

[Loosehead]

No, gravity effectively creates a flat earth (quiet Marge!) relative to the plane.

[maximus]

thanks guys im still a bit confused though . cheers loose that makes a bit of sense

[Clanad]

The instrument used for altitude reference is the altimeter (clever, no?).  Below and altitude of 18,000 feet it has a small barometric window that is reset often to the local barometric setting, i.e., the barometric pressure of the air locally.  Above 18,000 feet, all altimeters are set at a standard of 29.92 inches of mercury, at least in the U.S.  In European countries, another window referencing millibars is used. This assures all aircraft are at the same pressure altitude. With the advent of electric altimetry, most of the settings are automatic.  However, most transport aircraft still have, as a standby, an old reliable barometric altimeter... So, the aircraft would stay at your referenced 30,000 feet but only by reference to the air pressure.  This may or may not be 30,000 feet above the ground.  On instrument approaches in bad weather, a radar altimeter is used for exact heighth above ground, but these generally only work at 3,000 feet or so above the surface... By the way, Australia and some other countries have differences in terminology and altitudes at which settings are changed, but it's basically the same system...

[MargeB]

You're all wrong. The earth is flat (kags, back me up). If he points the nose too high he will shoot off. If he keeps going too long he'll fly off the edge anyway, so it's academic...

You know I speak sense.

[brachiopod]

Loosehead !! See what you started all over again !!!!

You don't even have to say 'Flat earth' three times for Marge to turn up !!

;o)

[Skids]

Barometric altimeters don't need adjusting but his gyroscopes will.  If he was to fly by the pitch gyroscope (without adjusting it) he would go in a dead straight line and head off into space.

[commoner]

....problem there Skids.........he would have to be doing 25,000 MPH to get into space and not too many planes can do that....Escape velocity and all that!..remember?  <G>

[maximus]

thank you skid that is precisly (cant spell) what i meant