What does QNH mean?
(video coming VERY soon!)
QNH is a Q code that denotes the barometric pressure at sea level. You can see a QNH value in the ATIS for example, this is the current barometric pressure at the airport. Setting your QNH, or barometric pressure, correctly in your altimeter is important, otherwise you are not flying on the correct altitude, because the altimeter calculates altitude based on the air pressure of the environment. QNH is given in hectopascal, but in the US the notation of “altimeter” is more common which uses inch/mercury. More in the video above!