When does Battery 1 assist with engine start?

Battery 1 assists with engine start at 10% Ng or 10 seconds after starter activation because this is designed to provide additional power during the critical phases of starting the engine. When the starter is engaged, the engine requires sufficient electrical power to turn over effectively. The activation of Battery 1 at this point ensures that there is adequate electrical availability to sustain the starting process, particularly as the engine is coming up to its idle speed.

The requirement for Battery 1 to engage at a specific Ng level or after a set time ensures a controlled and reliable engine start sequence. This approach minimizes the risk of the engine failing to start properly due to inadequate voltage supply during the initial stages, thus enhancing the safety and reliability of the operation. The timed or Ng-dependent activation allows for optimal performance and efficiency of the starting system, ensuring that the engine reaches the necessary operational parameters smoothly.