1. Electric Starter: This method is commonly used in smaller aircraft and generally involves two steps:
- Engage the Starter Motor: The starter motor is an electrical motor that is connected to the engine's gearbox or other suitable connection point. When powered, it rotates the engine shaft and provides initial motion to the engine.
- Fuel Introduction: Once the starter motor begins to turn the engine shaft, fuel is introduced into the combustion chamber through fuel injector nozzles. The rotating engine shaft creates airflow, which mixes with the introduced fuel.
2. Air Start: This method is commonly used in larger aircraft, where the available electrical power may be insufficient to start the engine. Air start involves the use of an external power source to provide high-pressure air, typically from a ground-based air start unit or an auxiliary power unit (APU) onboard the aircraft:
- External Air Supply: High-pressure air from the external source is connected to the engine's starter port or air inlet. The air is usually heated to improve its efficiency.
- Engine Rotation: The high-pressure air spins the engine's turbine blades, which in turn rotate the engine's shaft and initiate the engine's rotation.
- Fuel Introduction: Once the engine is rotating at a sufficient speed, fuel is introduced into the combustion chamber, which ignites and sustains the engine's operation.
It's worth noting that the specific procedures and equipment used for starting jet engines may vary depending on the aircraft type and the airline's operating procedures.
