Altimeter Question

On Apr 18, 2:20*am, terry wrote:
On Apr 17, 11:29*pm, 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

I wasnt aware you dont use the QNH term in the States. *So what do you
call the number you dial up to make the altimeter read airport
elevation?- Hide quoted text -


That's a good question as Eurocontrol recognises QNH as the correct
local barometric setting (they also state that it means Query: Newlyn
harbour). I thought the ICAO agreed with Eurocontrol on these things?

Cheers

WingFlaps schrieb:

That's a good question as Eurocontrol recognises QNH as the correct
local barometric setting (they also state that it means Query: Newlyn
harbour). I thought the ICAO agreed with Eurocontrol on these things?

Actually, it's the other way round: Eurocontrol adheres to the ICAO
phraseology.


From The ICAO Manual of Radiotelephony (ICAO Document 9432)

Glossary:
QNH: Altimeter sub-scale setting to obtain elevation when on the ground

Example:
Fastair 345, descend to 4000 feet, QNH 1005, transition level 50, expect
ILS approach runway 24

WingFlaps wrote:
On Apr 18, 2:20 am, terry wrote:

On Apr 17, 11:29 pm, 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

I wasnt aware you dont use the QNH term in the States. So what do you
call the number you dial up to make the altimeter read airport
elevation?- Hide quoted text -



That's a good question as Eurocontrol recognises QNH as the correct
local barometric setting (they also state that it means Query: Newlyn
harbour). I thought the ICAO agreed with Eurocontrol on these things?

Cheers


QNH is local barometric pressure reduced to mean sea level.

The local barometric pressure without altitude correction is QFE.

(At least here in the North-East corner of Eurocontrol area)

--

Tauno Voipio
tauno voipio (at) iki fi

terry wrote:
I wasnt aware you dont use the QNH term in the States. So what do you
call the number you dial up to make the altimeter read airport
elevation?


"Altimeter" or "altimeter setting". ATC always just says "altimeter".



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com

Terry,

So what do you
call the number you dial up to make the altimeter read airport
elevation?


altimeter setting. It is given in inches Hg, too, with 29.92 being
equivalent to 1013 hectoPascal. The Brits use another non-SI unit,
namely millibars, which is the same as hectoPasal.

--
Thomas Borchert (EDDH)

On 2008-04-17, terry wrote:
I wasnt aware you dont use the QNH term in the States. So what do you
call the number you dial up to make the altimeter read airport
elevation?

Altimeter or altimeter setting. For example, "Fairmont altimeter two niner
niner eight".

In radio procedure, using Q codes in speech is technically improper,
although it's done all the time (at least on the ham bands). The FAA, being
sticklers for proper procedure, would naturally include this bit. There are
no Q codes in use in aviation in the US any more, TTBOMK.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (FRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC (ordered 17 March, delivery 2 June)

In radio procedure, using Q codes in speech is technically improper,
although it's done all the time (at least on the ham bands). The FAA, being
sticklers for proper procedure, would naturally include this bit. There are
no Q codes in use in aviation in the US any more, TTBOMK.

So...what would you say instead of "Request QDM" in the U.S.? "Request
magnetic bearing to your station"? Sounds clumsy.

The most important Q-codes still in use here in Germany are probably QNH,
QFE, QDM, QDR.

Larry,

http://www.acronymfinder.com/acronym.aspx?rec={8F1A7DDE-89E8-11D4-8351-00C04FC2C2BF}
What does QNH stand for?
Atmospheric Pressure (Q) at Nautical Height (aviation)


That's hilarious!

--
Thomas Borchert (EDDH)

Thomas Borchert schrieb:

http://www.acronymfinder.com/acronym.aspx?rec={8F1A7DDE-89E8-11D4-8351-00C04FC2C2BF}
What does QNH stand for?
Atmospheric Pressure (Q) at Nautical Height (aviation)

That's hilarious!

Their second database entry is even more hilarious:
Queens Nautical Height.
:-)))

On Thu, 17 Apr 2008 12:57:57 GMT, Larry Dighera
wrote:

On Thu, 17 Apr 2008 02:20:46 -0700 (PDT), terry
wrote in
:

I am confused by this practice commercial nav question. ( at least I
am confused by the answer in the book which was b. but I think both a
and c are correct), but I appreciate some other opinions.

Day 1 Altimeter reads elevation of 1390 feet with 1013 HPa set on
subscale

http://en.wikipedia.org/wiki/Mbar
Atmospheric air pressure is often given in millibars where
"standard" sea level pressure is defined as 1013.25 mbar (hPa),
equal to 1.01325 bar. Despite millibars not being an SI unit, they
are still used locally in meteorology in some countries to
describe atmospheric pressure. The SI unit is the pascal (Pa),
with 1 mbar = 100 Pa = 1 hPa = 0.1 kPa. Meteorologists worldwide
have long measured air pressure in millibars. After the
introduction of SI units, others use hectopascals (which are
equivalent to millibars) so they could stick to the same numeric
scale. Similar pressures are given in kilopascals in practically
all other fields, where the hecto prefix is hardly ever used. In
particular, Canadian weather reports use kilopascals (which could
also be called centibars).


Torricelli started it all off. if you are the first guy in the world
with a barometer what do you call the measure of the atmospheric
pressure measured on that barometer. a bar(ometer). divide the value
into a thousand to give you some nice fine numbers to measure with and
you have the millibar.

pascal is just a johhny come lately in pressure measurements.

the poms worked out that 14.8lbs per square inch = 1 bar(ometer)

Stealth ( I'm with torricelli) Pilot