ATC phraseology

[pablodelmastro]

Hi everybody,
Lets say you are flying at FL290, you request to descend, and you are cleared to descend and maintain 3000 thousand feet.
When do you set the QNH or current altimeter setting?
When you are cleared to an altitude or when you cross the transition level?

[Dozza2k]

I was always told its when you are cleared to that altitude, unless they ask you to report passing another FL, then set QNH immediately after that

[No_Speed_Restriction]

dozza, if you were cleared to an altitude I would set the qnh and start descending. you can always cross reference to your standby altimeter if required.

[flying_elvis]

On descents, as soon as I'm given a new altimeter setting I read it back and set it. Otherwise, if I wait, I'll forget what it was.

I also leave the standby set to 2992 until the transition altitude/level.

"Measure with a micrometer, Mark it with a paint brush and cut it with an Axe!"

[5milesbaby]

in the UK we are told that you will set the QNH as soon as you are cleared to an altitude unless we request a passing of a FL. In that senario then we expect you to select QNH as soon as passing the requested FL.