In a Jabiru light sport aircraft engine, what drives the integral alternator?

The integral alternator in a Jabiru light sport aircraft engine is driven by a flywheel that is connected to the crankshaft. This design allows the alternator to generate electrical power as the engine operates, effectively ensuring that the engine has a continuous supply of electrical energy for various systems, such as lighting and avionics.

The connection to the crankshaft means that the alternator will spin at engine speed, providing reliable output proportional to the engine's performance. This integral configuration also offers mechanical simplicity and reduces the need for additional external generators or complex systems.

In contrast, the other options do not provide the necessary mechanical link to drive the alternator effectively. The fuel pump, for example, does not generate power; an external generator is not part of the internal design of the engine; and while the ignition coil is crucial for generating spark, it does not function to drive the alternator. Thus, the flywheel driven by the crankshaft is the correct mechanism for operating the integral alternator in this engine configuration.