Startklarering

Startklarering, or start clearance, is an aviation term for the authorization from air traffic control that allows an aircraft to begin engine start procedures and related pre-takeoff actions. The clearance is typically issued by ground control or the control tower when the taxi route to the runway is known and it is safe to prepare for departure. It is part of the sequence of ground operations that leads to takeoff.

In practice, start clearance may be given before or as part of pushback and engine start, and it may specify restrictions or instructions such as which engines may be started, the order of starts, power settings, and timing to ensure adequate separation from other traffic. After completing the engine start and initial power checks, the crew will request taxi clearance to move toward the runway. When ready for departure, the controller then issues takeoff clearance.

Regional practice varies. Under ICAO standards, there is typically a specific instruction to start engines or a start-up clearance, but the exact wording and necessity can differ by country, airport, and operator. In some operations, engine starts occur after the aircraft has been cleared to taxi without a distinct start clearance.

Safety considerations include avoiding engine start activities near other aircraft or ground equipment, ensuring the area is free of foreign object debris (FOD), and complying with noise and airspace restrictions. Startklarering is one step in the coordinated process of getting an aircraft from stand to takeoff.