Atimeter settings (correction)
 

How long has ATC used the terms "QNH" and "QFE" for altimeter settings, and how long has the UK used millibars for altimeter settings, was those terms used (and millibars) during WWII? I know the USA used inches of mercury and usually does not refer to the Q codes for altimeter settings, just "altimeters", does that mean above field or MSL?
Luke

Dunno the answers Luke but as a matter of interest (I see you are a new Ppruner) you can use the 'edit' function if you want to alter a post ;)

Luke
The "Q" codes date back to "HF" aka High Frequency radio transmission, aka Morse Code! Every tx was as short as poss [for obvious reasons]. Any "really" ancient STPO/WTO could give you a "full" translation.
From what I can remember, QNH Regional applied "Sea Level Atmospheric Pressure"
QFE Aerodrome Altitude Pressure
QGH Climb [in orbit] to cruising level above a/f
In short, [Regional] QNH means that ALL a/c "should" be on the same setting, and hopefully miss t'other one
QFE Your altimeter reads zero on the ground
"Standard" QNH 1013.2mb/29.92in is used for flying above the transition level [approx 4500ft] so that ALL a/c KNOW that they are separated by 1000ft on Airways, or even IFR in the "Bundu" :confused:
hope this helps
we aim to please, it keeps the cleaners happy

Luke, the USA "altimeter setting" is the QNH.

Hug,
"Barrocks!
QNH is "Regional Pressure Setting" either in "Inches" or "Milibars" :p
we aim to please, it keeps the cleaners happy

This thread already exists in the tech log forum