Hi all!

I've been trying without success to use the cutback option in the FMC.

When I get to the T/O ref page it allows me to select custom altitudes for other options (restore/cutback/reduction, etc.) but the option Cutback ON/OFF is unresponsive.

By clicking on the corresponding LSK nothing happens.

I thought it was a conflict with the altitudes I selected and tried to change them around with no success.

Is it something else? maybe thrust reduction interfering?

Can anybody point me in the right direction?

Cheers,

Sounds like there's a misunderstanding of what it is/does:

Check out page 0.00.29 of the Introduction Manual. CUTBACK is explained there.

Is everything complete in the previous pages of the Take off Ref and PERF INIT ? No empty squares? It won't work if the speeds V1 VR V2 etc are not selected?

 

This can sometimes get reset if you select another runway or change the wind in the TAKE OFF REF.

Ah ha! That must be it. Since cutback is on the take off page 2, which I select before entering the to speeds to imput the rwy wind I must have tried to activate it before selecting the v speeds! Thank you so much!