Take-off alternate – an alternate airport at which an aircraft can land, if necessary, shortly after take-off when it is not possible to return to the airport of departure.
En-route alternate – an airport at which an aircraft would be able to land after experiencing an abnormal or emergency condition while en route.
ETOPS en-route alternate – a suitable and appropriate alternate airport at which an aircraft would be able to land after experiencing an engine shutdown or other abnormal or emergency condition while en route in an ETOPS operation.
Destination alternate – an alternate airport to which an aircraft may proceed should it become either impossible or inadvisable to land at the airport of intended landing.
Altitude Bust
Any deviation from an assigned altitude or flight level.
Equivalent Terms: Altitude Deviation, Level Bust, Altitude Acquisition Error Altimeter Reference Setting
The reference to which the barometric altimeter is set to indicate a defined altitude as required for the area of operations.
QNH – an altimeter setting derived from a station that will cause the barometric altimeter to indicate a height above mean sea level over that station.
QFE – an altimeter setting derived from a station that will cause the barometric altimeter to indicate the height above that station.
QNE – an altimeter setting at the ISA standard pressure of 1013.2 hPa or 29.92 in Hg. Anti-Icing
A precautionary process for protecting clean aircraft surfaces against the formation of ice and frost, and the accumulation of snow and slush for a limited period of time.
Approval (State or Authority) See State Approval.
Approved Agencies
Operators or AMOs that are approved by the applicable NAA and/or another operator to perform aircraft maintenance.
Approved Data
Approved Data consists of:
ƒ directly applicable Manufacturer's Manuals and procedural information;
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