QNH (Questions Need Hanswers)

Technical questions, advice, sharing information etc (aircraft, engines, instruments, weather and such)
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Guzz
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QNH (Questions Need Hanswers)

Postby Guzz » Fri May 11, 2007 10:41 am

Can anyone give me a quick rundown of the following:

What does QNH stand for?
What effect does it have on the plane if it's high or low?
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Morph
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Postby Morph » Fri May 11, 2007 10:56 am

Query Nautical Height, i.e. the height above sea level. Here you set your altimeter to the known height an airfield has above sea level before take off. The altimeter will show altitude as AMSL (above mean sea level)

QFE is Query Field Elevation, Here you set your altimeter to 0ft while at the airfield. It will thus show altitude as AGL (Above Ground Level)
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Arnulf
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Postby Arnulf » Sun May 13, 2007 9:34 pm

If the QNH is high, your aerie will perform better than if it is low.
For Microlights the effect is probably negligable. For take-off peformance calculations in airliners the QNH is taken into consideration.

Regards,
Arnulf
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Morph
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Postby Morph » Sun May 13, 2007 11:02 pm

I dont think I was particularly clear on my previous post.

Before flying you set your altimeter to the known altitude of the airfield. the little gauge on the altimeter then gives you a reading in Millibars which represents the air pressure at that particular place. A higher aipressure indicates stable conditions and lower air pressure indicates unstable conditions and the possibility of a cold front. It is better to fly in higher pressure conditions.
Greg Perkins
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Guzz
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Postby Guzz » Mon May 14, 2007 12:29 pm

Aha! :idea: Got it!

Thanks chaps :D
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ZULU1
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All the Answers

Postby ZULU1 » Wed May 16, 2007 6:06 am

Take a look at this site, it has everything you need to know about "Q" codes and origins of same : http://www.kloth.net/radio/qcodes.php

except QUANTAS !!

eish Zulu1
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skydiver
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Postby skydiver » Mon May 21, 2007 8:03 am

It's QANTAS, not QUANTAS. It was originally a set of initials that stood for Queensland and Northern Territory Air Service. Started as a single airplane service in a small country town in Queensland in Australia. :)
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swiftprop
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Postby swiftprop » Fri Jul 27, 2007 7:14 pm

Many thanks Morph and Zulu1. This also makes it easier to remember. I have been asking people for years and no one has so far been able to say what they stand for except reference to the "Q"codes.
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Postby skyvan » Fri Jul 27, 2007 9:15 pm

Q ueers
A nd
N ancies
T rained
A s
S tewards

:twisted: :twisted: :twisted:
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John Young
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Better on a camel

Postby John Young » Sat Jul 28, 2007 4:41 am

S uch
A
B loody
E xperience
N ever
A gain

B end
O ver
A gain
C aptain

B etter
O n
A
C amel

L et
U s
F ook
T he
H ostess
A nd
N ot
S ay
A nything

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