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PBT: Pushback/towing - Aircraft is moving in the gate, ramp, or parking area, assisted by a tow vehicle (tug).
This phase of flight includes the following sub-phases:
- Assisted, Engine(s) Not Operating
- Assisted, Engine(s) Start-up
- Assisted, Engine(s) Operating
- Assisted, Engine(s) Shut Down
- Unassisted movement in the gate or ramp area is included in the TAXI phase.
- Engine shutdown is from the start of the shutdown sequence until the engine(s) cease rotation