ATS fail and can’t re engage

[piperpilot99]

During climb, ATS fails and I can’t re engage it. Have tried TOGA/ auto throttle disconnect etc but nothing works. Any suggestions please?

[rjb4000]

Could you post a screenshot of your PFD/MFD when the failure is occurring?

[piperpilot99]

Sure

[rjb4000]

You need to have an N1 target for ATS to operate. Select PERF on the FMC to select an N1 target mode. 

[piperpilot99]

19 minutes ago, rjb4000 said:

You need to have an N1 target for ATS to operate. Select PERF on the FMC to select an N1 target mode. 

Thanks for this but please can you give me a little more info on how N1 target mode is selected?

[danhenri]

Thrust Limit page of PERF menu : select N1 thrust on the left side of the screen. Before landing, don't forget to select a N1 target (90 for example) on the right. It becomes blue when activated.

Edited April 9, 2022 by danhenri

[Pils]

1 hour ago, piperpilot99 said:

Thanks for this but please can you give me a little more info on how N1 target mode is selected?

ATS needs an N1 thrust limit. It doesn’t care which preset one (or a custom one in TGT), that’s up to you.

[Pils]

21 minutes ago, danhenri said:

Thrust Limit page of PERF menu : select N1 thrust on the left side of the screen. Before landing, don't forget to select a N1 target (90 for example) on the right. It becomes blue when activated.

TO is still acceptable for landing.

[danhenri]

Thanks "Pils", but on approach, the TO field is always blank when I set the N1 target. How may I get the TO preset again ?

[Pils]

9 minutes ago, danhenri said:

Thanks "Pils", but on approach, the TO field is always blank when I set the N1 target. How may I get the TO preset again ?

It should be populated below 15,000 ft. The safest choice is a manually set TGT (e.g. 90%) as it can never be invalidated, unlike the others which are based on finite lookup tables. The thrust limit only comes into play for a go-around.

[piperpilot99]

Thank you I’ll try that!

[danhenri]

15 hours ago, Pils said:

It should be populated below 15,000 ft. The safest choice is a manually set TGT (e.g. 90%) as it can never be invalidated, unlike the others which are based on finite lookup tables. The thrust limit only comes into play for a go-around.

Thanks for your answer.

Have a nice sunday.