In older reciprocating aircraft, where is the energy for cranking the engine stored?

The correct answer is that the energy for cranking the engine in older reciprocating aircraft is stored in the flywheel. The flywheel serves as a mechanical device that stores kinetic energy. It plays an essential role during the engine's cranking process by providing the necessary rotational force to start the engine.

When the engine is initially cranked, the flywheel's stored energy helps to overcome the inertia of the engine components, allowing for a smoother and more efficient start. The flywheel’s ability to maintain consistent rotational speed also aids in stabilizing the engine's operation once it has started.

In older reciprocating aircraft, this approach contrasts with some modern systems, where starter batteries might directly provide electrical energy for cranking. However, in the context of older aircraft, the flywheel's role becomes crucial for the mechanics of starting the engine.