APU Tank #2 Valve Logic Incorrect

[Joshua757_YT]

According to L1011 CBT:

"The fuel supply for the APU is taken by a taping in the #2 Engine Feed Pipe downstream of the Engine #2 Tank Valve. Because of this, if the Engine #2 tank valve is closed, the APU will be inoperative"

However, I found its possible to start the APU without the tank 2 switch latched in.

Hope this helps.

Cheers,

Joshua757

[IniJamir]

On 4/4/2026 at 10:43 AM, Joshua757_YT said:

According to L1011 CBT:

"The fuel supply for the APU is taken by a taping in the #2 Engine Feed Pipe downstream of the Engine #2 Tank Valve. Because of this, if the Engine #2 tank valve is closed, the APU will be inoperative"

However, I found its possible to start the APU without the tank 2 switch latched in.

Hope this helps.

Cheers,

Joshua757

Hello, this is a known issue that we already have logged. Thank you 🙂