The Aeronautical Code signals are radio signal codes. They are part of a larger set of Q Codes allocated by the ITU-R during the International Telecommunication and Radio Conferences in Atlantic City 1947 in Appendix 9 "Miscellaneous Abbreviations and Signals to be used in Radiocommunications", and documenten in the International Radio Regulations, Section I. Q Code.[1] The QAA–QNZ code range includes phrases applicable primarily to the aeronautical service, as defined by the International Civil Aviation Organisation.
First defined by ICAO (International Civil Aviation Organization) in ICAO Doc-6100-COM/504/1" "Communication Codes and Abbreviations. Q Code" published 1952.April.01[2] and today superseded by ICAO Doc-8400 "Procedures for Air Navigation Services, ICAO Abbreviations and Codes".[3] The majority of the Q codes published in ICAO Doc-6100 have slipped out of common use; for example today reports such as QAU ("I am about to jettison fuel") and QAZ ("I am flying in a storm") would be voice or computerized transmissions. But several remain part of the standard ICAO radiotelephony phraseology in aviation.
| The pressure set on the subscale of the altimeter so that the instrument indicates its height above the reference elevation being used [e.g. aerodrome elevation][4] | Runway in use 22 Left, QFE 990 hectopascals | ||
| Atmospheric pressure at a place, reduced to MSL using the actual temperature at the time of observation as the mean temperature. | |||
| During conditions of exceptionally low atmospheric pressure it is not possible to set QFE or QNH on some aircraft altimeters. In these circumstances an aerodrome or runway QNE can be requested. The QNE is the reading in feet on an altimeter withthe sub-scale set to 1013.2 hPa when the aircraft is at aerodrome or touchdownelevation.[5] | |||
| The pressure set on the subscale of the altimeter so that the instrument indicates its height above sea level (the altimeter will read runway elevation when the aircraft is on the runway). | Request Leeds QNH |
| QDM | Magnetic bearing to a station | (callsign) request QDM (callsign)[6] | |
| QDL | Series of bearings taken at regular intervals | ||
| QDR | Magnetic bearing from a station | (callsign) request QDR (callsign) | |
| QFU | Magnetic bearing of the runway in use | Runway 22 in use, QFU 220[7] | |
| QGE | Distance | (callsign) request QGE (callsign) | |
| QGH | Controlled Descent through Clouds (Royal Air Force use) | ||
| QTE | True bearing/track from a station | (callsign) request QTE (callsign) | |
| QTF | |||
| QUJ | True bearing/track to a station | (callsign) request QUJ (callsign) |
| QGH | controller-interpreted DF let-down procedure, on UHF or VHF[8] |
