Why would the AP not engage?

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Capitanfuturo
Posts: 317
Joined: 06 Nov 2013, 14:20
Location: Huizen, The Netherlands

Why would the AP not engage?

Post by Capitanfuturo » 18 Dec 2016, 11:33

For a while I get a sporadic situation that after take off and after having engaged VNAV and LNAV the AP does not want to engage,
I use the MCP EL version from CPFlight, however I do not think that it's hardware related.

Are there specific conditions where, in real life or simulated, the AP would not engage?
Maybe I do something wrong in my procedure flow but the other problem is that it does not always happen,
on the same flight plan it may happens 3 times out of 10 and when it happens I just cannot pin point what I did wrong.

Any suggestions for me?

Thanks
Nic

saabpilot
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Re: Why would the AP not engage?

Post by saabpilot » 18 Dec 2016, 11:47

A common "problem" :)

You need to have the aircraft fully trimmed out so there is no need for forward or backward pressure on the yoke.
If there is a negative or positive pressure sensed the A/P will not engage.
Thus when calibrating the yoke you need to establish a "dead zone" around the centered position.

Bjorn
Last edited by saabpilot on 20 Dec 2016, 12:31, edited 1 time in total.
I7 7700K@4.5, Nvidia 1070, 4x Esprimo I5 mini PC, Optoma HD proj, P3D v4.3, ORBX, RAAS Pro, ProATC-X, Buttkicker, CPF Pro MCP/EFIS, RSP motor TQ, OC v3 CDU, FDS Elite CDU
website = http://www.boeing737sim.se

Capitanfuturo
Posts: 317
Joined: 06 Nov 2013, 14:20
Location: Huizen, The Netherlands

Re: Why would the AP not engage?

Post by Capitanfuturo » 18 Dec 2016, 11:56

saabpilot wrote:A common "problem" :)

You need to have the aircraft fully trimmed out so there is no pressure on the yoke when centered.
If there is a negative or positive pressure sensed the A/P will not engage.
Thus when calibrating the yoke you need to establish a "dead zone" around the centered position.

Bjorn

This sounds like a very possible scenario, I know that when I take off I am a bit of an amateur and I fly all over the place with that yoke :-)

Do you know if for the ACE Yoke, is there a specific place to set the dead zone or can I just do it from the control panel of the windows PC?

Thanks
Nic

saabpilot
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Joined: 08 Jan 2011, 16:03
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Re: Why would the AP not engage?

Post by saabpilot » 18 Dec 2016, 12:01

I have a Ace yoke too, but have not calibrated it for years, very stable :)
But I believe you can verify the center dead zone in the Plasma 2 app (My Ace yoke has a Plasma 2 card) or Windows calibration.
I7 7700K@4.5, Nvidia 1070, 4x Esprimo I5 mini PC, Optoma HD proj, P3D v4.3, ORBX, RAAS Pro, ProATC-X, Buttkicker, CPF Pro MCP/EFIS, RSP motor TQ, OC v3 CDU, FDS Elite CDU
website = http://www.boeing737sim.se

river9999uk
Posts: 157
Joined: 16 Jan 2015, 15:24
Location: EGTE

Re: Why would the AP not engage?

Post by river9999uk » 19 Dec 2016, 12:12

As these guys have said let go of the yoke and then engage and it should work....that's what I do anyway :D

easy737
Posts: 1
Joined: 05 May 2017, 08:50
Location: Italy

Re: Why would the AP not engage?

Post by easy737 » 05 May 2017, 09:01

Thx for this Info !

I have the same problem ! LOL

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