What happens when you disconnect the autopilot?
Joined: Oct 2009
Posts: 1,270
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From: UK
Hi PENKO,
About the same as the Airbus Rudder. You know how much deflection is required by the "feel" of your displaced feet.
How much aileron deflection can you "feel" is being applied in Normal Law?
In Alternate Law, you can "feel" how much aileron is required by you side stick deflection.
Well, how much feel do you have in a 737 with its hydraulics and artificial feel?
How much aileron deflection can you "feel" is being applied in Normal Law?
In Alternate Law, you can "feel" how much aileron is required by you side stick deflection.
Joined: Mar 2005
Posts: 1,338
Likes: 1
From: Uh... Where was I?
In alternate law in roll, the feel is always the same for the same sidestick angle, irrespective of speed or anything else. No feedback at all. There is a relation between angle and roll rate, still, wich varies with circumstances, unlike in normal law. But I don't regard that as a way to feel.
Last edited by Microburst2002; 9th December 2012 at 14:34.
Joined: Dec 2007
Posts: 156
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From: Montreal
What happens when you disconnect the autopilot?
I guess this depends on the AP system and can vary a great deal.
My question would have been " Can the manual trim settings be changed with the AP engaged ?"
If so; disconnecting the AP in flight may cause minor to major changes in attitude, depending on trim settings.
If not, there should be only minor attitude changes initially.
A great deal also depends on the natural design in flight stability of the aircraft and the C/G
In any case, pilots should be "hands on" when changing the AP setting
just in case something has, nevertheless, hit the fan !.
My question would have been " Can the manual trim settings be changed with the AP engaged ?"
If so; disconnecting the AP in flight may cause minor to major changes in attitude, depending on trim settings.
If not, there should be only minor attitude changes initially.
A great deal also depends on the natural design in flight stability of the aircraft and the C/G
In any case, pilots should be "hands on" when changing the AP setting
just in case something has, nevertheless, hit the fan !.
Joined: Feb 2012
Posts: 14
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From: Germany
@Bloggs
"Say what? What is "neutral"??"
I guess he is referring to the trimmed 0 point of the control wheel's roll / aileron axis. Aileron trim can be used to offset this datum, but the AP will never use aileron trim and you should never touch it while the AP is engaged, as otherwise, as you disconnect the AP, the control wheel will 'jump' to this new datum and initiate a roll!
"Say what? What is "neutral"??"
I guess he is referring to the trimmed 0 point of the control wheel's roll / aileron axis. Aileron trim can be used to offset this datum, but the AP will never use aileron trim and you should never touch it while the AP is engaged, as otherwise, as you disconnect the AP, the control wheel will 'jump' to this new datum and initiate a roll!
Plumbum Pendular
Joined: Aug 1999
Posts: 1,117
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From: Avionics Bay
Can I suggest that you guys RTFQ!!
The question was about Airbuses, deliberate disengagement of the AP and I read it that the OP was not suggesting that there were any failures.
Therefore, at the risk of sounding arrogant, my answer is the only relevant one on this thread!
The question was about Airbuses, deliberate disengagement of the AP and I read it that the OP was not suggesting that there were any failures.
Therefore, at the risk of sounding arrogant, my answer is the only relevant one on this thread!
Joined: Jun 2002
Posts: 286
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From: Vega Constellation
Here's my 2 cents.
I fly the A320, and the 1G value is calibrated, not matching actual local acceleration. Typically, the force of gravity would be measured less than 1G near the equator, and I don't know the value one would read sitting at the poles, since I did not go there. In subtropical latitudes (East and South East Asia), the g displayed on the FMGC is less than 1, EVEN ON THE GROUND. Could it be due to slingshot effect as we get closer to the equator?
Typical values in flight always showed me less than 1G, so assuming that the Airbus books are correct and precise, disconnecting the AP would indeed revert to maintaining 1G instead of ALT, thus causing a very slight but noticeable climb.
If this does not happen on 330/340, maybe this minor flaw was corrected by software, but I don't have any experience on those types.
Should not be much of an issue anyways, how long do you want to have the aircraft flying hand off without an autopilot?
Flex
I fly the A320, and the 1G value is calibrated, not matching actual local acceleration. Typically, the force of gravity would be measured less than 1G near the equator, and I don't know the value one would read sitting at the poles, since I did not go there. In subtropical latitudes (East and South East Asia), the g displayed on the FMGC is less than 1, EVEN ON THE GROUND. Could it be due to slingshot effect as we get closer to the equator?
Typical values in flight always showed me less than 1G, so assuming that the Airbus books are correct and precise, disconnecting the AP would indeed revert to maintaining 1G instead of ALT, thus causing a very slight but noticeable climb.
If this does not happen on 330/340, maybe this minor flaw was corrected by software, but I don't have any experience on those types.
Should not be much of an issue anyways, how long do you want to have the aircraft flying hand off without an autopilot?
Flex
