Altimeter Question

On Apr 18, 1:29*am, Stefan wrote:
Larry Dighera schrieb:

*http://en.wikipedia.org/wiki/Mbar

Mbar would be a tad much. You certainly meant mbar.

* What does QNH stand for?
* Atmospheric Pressure (Q) at Nautical Height (aviation)

Bull****. QNH is *not* an acronym. It's one of over hundred Q-Codes
which were defined in the stone age of radio telephony. The letters were
randomly chosen, think of it as a numeration. Most of those Q-Codes are
forgotten today, but a few still live. In aviation, I mean in aviation
in all coutries except the USA, QNH, QFE and QNH are used to define
different altitude settings (roughly spoken).

QNH stands for the pressure you must tune in the kollmans window to have
the altimeter display the airport elevation when the airplane sits on
the ground. (As opposed to QFE, which ist the pressure to set for the
alitmeter to display zero on the ground and QNE, which is the altitude
which the alitmeter shows on the ground when it is set to standard
atmosphere.)

For those who believe in Wikipedia:http://en.wikipedia.org/wiki/Q-code

QNH means query Newquay Harbour which was the British reference for
sea level.
It should give the atmospheric pressure at that dtaum -but I doubt
that the met offices bother to check what the actual height of that
datum is...

Cheers

WingFlaps schrieb:

QNH means query Newquay Harbour which was the British reference for
sea level.
It should give the atmospheric pressure at that dtaum -but I doubt

You certainly can cite a source for this urban legend?

On Apr 18, 1:53*am, Stefan wrote:
WingFlaps schrieb:

QNH means query Newquay Harbour which was the British reference for
sea level.
It should give the atmospheric pressure at that dtaum -but I doubt

You certainly can cite a source for this urban legend?

Urban legend? O, it was not Newquay but Newlyn (both in cornwall). The
datum is sea level as set the British Admiralty back then so the
obvious Q code would have been QNH. Look up the history of the naval
tidal observatory if you don't believe it.

Cheers

On 2008-04-17, WingFlaps wrote:
Urban legend? O, it was not Newquay but Newlyn (both in cornwall). The
datum is sea level as set the British Admiralty back then so the
obvious Q code would have been QNH. Look up the history of the naval
tidal observatory if you don't believe it.

Source, please. The Q codes are just as Stefan said: randomly assigned.
They were chosen that way so as not to conflict with any nation's callsign
blocks (to this day, there are no callsigns assigned with Q as the first
letter). The apparent relationship between QNH and Newlyn Harbor is purely
coincidental.
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