A level bust, also known as an altitude deviation, occurs when an aircraft fails to fly at the level for which it has been cleared. A level bust is defined by EUROCONTROL as: "Any unauthorised vertical deviation of more than 300 feet from an ATC flight clearance."
Contents
This may take one of three different forms:
- An aircraft in level flight climbs or descends without clearance
- An aircraft climbing or descending fails to level off accurately at the correct level (either passing through and continuing the climb or descent, or passing through and then returning to the correct level)
- An aircraft levelling off at the correct level or altitude, but with an incorrect altimeter setting
Causal factors
Accidents and serious incidents involving level bust
References
Level bust Wikipedia(Text) CC BY-SA