What is the maximum time allowed for dry motoring sequences?

The maximum time allowed for dry motoring sequences is 30 seconds. This parameter is designed to ensure safe operational practices during engine start procedures. Dry motoring is utilized to verify the engine's operational condition by rotating the engine without fuel or ignition, allowing the pilot to check various systems before an actual start.

Keeping the dry motoring period to a maximum of 30 seconds helps to avoid excessive wear and heat buildup in the engine components, particularly in the starter and associated systems. Compliance with this time limit ensures that the engine remains in a safe operational state while also preserving the integrity of the starter and related equipment.

It's important to adhere to these limits to maintain aircraft safety and performance standards, which is why the 30-second duration is established as the maximum.