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, 2:40 am, Gig 601Xl Builder
wrote:
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

Nope. If you dial up the local barometric pressure the altimeter may
not read airfield elevation....

Cheers

GO away no fly boy.

On Apr 18, 4:06*am, Gig 601Xl Builder
wrote:
WingFlaps wrote:
On Apr 18, 2:40 am, Gig 601Xl Builder
wrote:
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

Nope. If you dial up the local barometric pressure the altimeter may
not read airfield elevation....

Cheers

GO away no fly boy.

I see you don't know. In fact an altimeter is calibrated to the
standard atmosphere so if the temp. is not standard it will not read
field elevation when local QNH is applied.

Pretty basic knowlege for a PPL, Oh I forgot, I'm not supposed to be a
pilot.

Cheers

On Apr 18, 3:58*am, Stefan wrote:
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

WTF are the Americans doing not using ICAO standards or is it just
Gig601 being wrong?

Cheers

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

Hi,

In article ,
Bertie the wrote:
They don't use any of the Q codes in the US. QNH is one of the few still
in use around the rest of the world, the rest are pretty much archaich.
You stil occasionally hear QFE in the UK, but no airlines I know of are
using it anymore since modern airplanes aren't designed around their use
(QFE settings on the altimeter **** up the computers since the computer
is anticipating a QHN setting to run a bunch of other devices in the
airplane, of which pressurisation is the most relevant) Very
occasionally you hear QSY which is "see you, I'm going to talk to
someone else" and QDM almost never nowadays, but it used to be
relatively common and it's Mag direction to a station. And even less
used QDR which is the Mag radial from a station. I think the Maritime
world might use a lot more of them still, though.

The UK PPL syllabus still teaches QNH, QFE (the military use it here, and
some civil airfields will give it in the initial response). QDM, QDR and QTE
(true bearing) are also taught. QDM is on the R/T 'practical' test
generally.

Andy

On Apr 18, 3:04*am, Bertie the Bunyip 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?

They don't use any of the Q codes in the US. QNH is one of the few still
in use around the rest of the world, the rest are pretty much archaich.

How come the US doesn't adopt ICAO? I thought it had to -isn't that
what ICAO is all about?

Cheers

WingFlaps schrieb:

I see you don't know. In fact an altimeter is calibrated to the
standard atmosphere so if the temp. is not standard it will not read
field elevation when local QNH is applied.

Wrong.

From The ICAO Manual of Radiotelephony (ICAO Document 9432) Glossary:
QNH: Altimeter sub-scale setting to obtain elevation when on the ground

So an altimeter set to local QNH will always read field elevation *by
definition*.

Pretty basic knowlege for a PPL

Indeed.

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