above ground level

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above ground level (AGL)

The height of an aircraft above ground level. Also known as absolute altitude. It is measured by a radio, radar, or laser altimeter. When an aircraft is required to fly at a certain height above ground level, the AGL refers to its average height above terrain, not above certain high features and obstacles that may be in the area of operation. If the aircraft is to fly at a fixed height above all obstacles and features, then the height is above obstruction level (AOL), not above ground level. The former may be greater than or equal to the AGL. See above obstruction level.
References in periodicals archive ?
Push diem into a trench with just a bud or two above ground level or into a tall pot in open, gritty compost.
If the ground water level is below this then the bricks above ground level will become damp but they won't often be saturated.
They'll head up on on a 620ft long fabric walkway suspended on tensile cables 174ft above ground level to an observation platform at the summit.
The divers jumped form 6,000-8,000 feet above ground level before their parachutes opened and let them touch down at more than 200 kilometers per hour.
The structure of the airframe compressed into the principle impact crater so that the leading edges of the horizontal stabilizers were inches above ground level.
At 40 storeys high and 125 metres above ground level, West Tower, in Brook Street, will dwarf other landmark Liverpool developments such as the Anglican Cathedral at 100.
Train them to wires 30cm above ground level so that they grow in opposite directions.
The smaller block houses six studio flats, while the large, block has four storeys of communal flats (each for five to six people occupying an entire floor) set above ground level shop units.
Dalek hatches a cunning plan for getting above ground level
Untangle growth and remove up to one- third of the oldest flowered shoots to just above ground level.
No mention is made of the effects on people in Wales, when these aircraft fly over our homes at 500mph and 30 metres above ground level.