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Setting QNH in the UK

Hi Everyone,

I recall that when on descent in the UK and cleared to an altitude from a flight level, we would set QNH, no matter what level we were at when cleared. Is this still the case? I can't find any reference to this. Or is QNH now set at the TL?

Thanks everyone for any guidance.

Regards.

What does your Ops manual say? Ours says you set QNH when cleared to an altitude. In reality it will make little difference as you rarely seem to get cleared to an altitude in the UK from more than a couple of thousand feet from transition.

From the Jepessen UK procedures publication:

Quote:

ALTIMETRY

Within controlled airspace a pilot should set one altimeter to the latest aerodrome QNH prior to take-off. While flying at, or below, the transition altitude vertical position will be expressed in terms of altitude based upon the aerodrome QNH. When cleared for climb to a flight level, vertical position will be expressed in terms of flight level, unless intermediate altitude reports have been specifically requested by ATC.

When an aircraft is descended from a flight level to an altitude preparatory to commencing approach for landing, ATC will pass the appropriate QNH. In addition, ATC will also pass the Transition Level in due time prior to reaching it during descent either by voice communications, ATIS broadcast or if available, data link. On vacating the flight level, the pilot will change to the aerodrome QNH unless further flight level vacating reports have been requested by ATC, in which case, the aerodrome QNH will be set following the final flight level vacating report. Thereafter, the pilot will continue to fly on the aerodrome QNH until established on final approach. When requested by the pilot or local procedures require, the appropriate QFE and aerodrome or threshold elevation shall also be given. When carrying out a radar approach, ATC will assume that an aircraft is using QNH on final approach and will include a reminder of the appropriate QNH setting in the RTF phraseology. If the pilot requests to undertake the approach using QFE, then ATC will pass the appropriate QFE and "height" will be substituted for "altitude" in the RTF phraseology. It should also noted that the OCH is always given with reference to the aerodrome or threshold elevation.

From the UK AIP, ENR 1.7 Altimeter Setting Procedures:

Quote:

5.3.1 When an aircraft is descended from a Flight Level to an Altitude preparatory to commencing approach for landing, ATC will pass the appropriate aerodrome QNH. In addition, ATC will also pass the Transition Level in due time prior to reaching it during descent either by voice communications, ATIS broadcast or if available, data link. On vacating the Flight Level, the pilot will change to the aerodrome QNH unless further Flight Level vacating reports have been requested by ATC, in which case, the aerodrome QNH will be set following the final Flight Level vacating report. Thereafter, the pilot will continue to fly on the aerodrome QNH until established on final approach. When requested by the pilot or local procedures require, the appropriate QFE and aerodrome or threshold elevation shall also be given.