The engine start sequence is explained, highlighting the actions taken by the First Officer and Captain, including necessary ...

Jet engines can't just start with the push of a button. We explain what jets need to get them going, and why there needs to be more than one option.

An Air Start Unit (ASU) is a pneumatic starting system. Most jets use an Auxiliary Power Unit (APU) but the ASU is an essential backup if it's not working.