Difference Between QNH, QFE and QFF

This video explains concepts of QNH, QFE and QFF and their importance in altimetry and the study of pressure systems that affect weather. It also shows the methods by which their values are calculated with graphic examples.
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[@lihaotao4912]

Good video which is more detail than FAA website document.

[@weasel07]

Great video ! Outstandingly well done, close to perfectly explained

[@HamedNarimani]

perfect video so useful, i just realised the reason for cold temp correction during approach

[@RAFMuffler]

Thanks for this video! Pretty simple and nice explanation of complex things.

[@metaloper]

Perfect explanation! Thanks!

[@glennrodney7471]

Outstanding video!! Well done

[@renatoserzanink629]

Excellent explanation and video!! Congrats for the great work!! .. Just as a suggestion, the automatic "sniff" sound that comes up regularly should be less frequent.

[@farhanhaider5992]

Great explanation

[@hayrlsylabigideydik6191]

Great video! Thanks!

[@aviatube4419]

Great video, but there is a question. In last example, how you get QNH 1010 hpa, what pressure lapse rate did you use to get it?

[@kairetzu]

Very useful !!

[@aviationworld1142]

thanks for sharing

[@leonardoaraujo5520]

Thank you very much 🙏🏽🙏🏽

[@rachel03]

this has been very helpful. do you have any more videos for meteorology ?

[@chalitha22]

Thanks for the video!

[@kevindetolli]

where can I check QFF for weather stations?

[@raccoonair]

Very well done, related to meteorology, but for aviation purposes QFF is never used, QFE hardly, but provides height, relative to the airports elevation and will read 0 feet when landed, QNH the LOCAL pressure relative to sea level, providing altitude and the QNE relative to the standard plane of 29.92 inches/ 1013 hPa for Flight levels. Thanks for sharing though.

[@raccoonair]

@@Hans_Magnusson Yep, sorry. typo. I was already changing it 😀. Good stuff, nice animations... keep it up!

[@AviationTheory]

Hi Raccoon, you are right! This video is more focused on how these concepts are used in general meteorology rather than in practical altimetry procedures.
You can find more detailed information on how they are actually used in aviation in our video “Altimeter Setting Procedures and Altimetry”: th-cam.com/video/9VEVUVS7fbg/w-d-xo.html

[@raccoonair]

@@AviationTheory Thanks; Aviation meteo is by far the most involved topic within aviation training. Good to see it now from a meteorological viewpoint, other than its view from aviation perspective.

[@shanelodge391]

If you fly internationally you will encounter QFE, eg Russia.

[@raccoonair]

@@shanelodge391 Yes, I also know that the QFE is provided in clearances in the UK.

[@Uluc994]

How did we find 105 hPa pressure difference at 5:41? Shouldn't 3000 ft result in 100 hPa difference?

[@pilottadeus3748]

"Now calculating the QNH is not so simple since the correct vertical pressure gradient to be applied must be determined as a function of the standard temperature as we descend."
What exactly is meant with that sentence?

[@farxadalizade599]

hi, thanks for video. but i cant find qff=1005hpa in last calculation. if T=28, 273+28= 301, 301*96/2000= 14ft. 2000/14= 143 hpa?? what in my calculation is wrong?

[@s920356]

check 11:14
for 301*96/2000
you mean your QFE is 2000 hPa?

[@ragzpar]

It should be 301*96 divided by 940 and not divided by 2000. Divide by Qfe and not the field elevation.

[@manueladao8653]

Good. Just a question. Is the formula QNH=QFE+Alt(feets)/27 Correct?

[@VasiliyBoyko-nr9jb]

yes, if you use the standard values and below 20000ft, because upper FL200-400 1hPa equals to 50ft

[@meow121.5]

NOW