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Manually overriding autothrust

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Manually overriding autothrust

Old 1st Oct 2013, 21:48
  #61 (permalink)  
 
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Hi DozyWannabe,
When A/THR is disengaged (or automatically disengages) then the thrust remains at the last setting prior to disconnect.
Only if "Thrust Lock" was activated.

The only way you'll end up in the situation you're describing is.....Or if they were in the climb detent at disconnect, you'd have to "jiggle" the levers and leave them in the climb detent/region - not recommended procedure in any aircraft, including "your" Boeing!
"Jiggling" is not necessary. Simply disengage auto thrust using the "instinctive disconnect buttons" on the T/Ls and you'd have set Climb Power.
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Old 1st Oct 2013, 22:21
  #62 (permalink)  
 
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You're right, rrr - I got myself muddled with A/THR disconnect via the FCU switch (which will, I believe, result in Thrust Lock activation). The "instinctive" switches require the levers to be set before disconnect.
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Old 2nd Oct 2013, 02:01
  #63 (permalink)  
 
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Originally Posted by dozy
When A/THR is disengaged (or automatically disengages) then the thrust remains at the last setting prior to disconnect.
Negative, at A/THR disconnect thrust could increase to climb thrust from idle prior to disconnect.

The only way you'll end up in the situation you're describing is if you move the thrust levers to the climb detent after disconnecting.
Absolutely not. The situation described by Capn Bloggs is totally accurate.

Originally Posted by Altcrznav
I was going off of vilas' post. He shows a 2011 date for the bulletin.
The bulletin as posted by vilas is an amendment of the original bulletin.
After 15 years on the bus I am still surprised you have never been aware of such procedure as the Flight Crew Bulletins are part of the FCOM.
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Old 2nd Oct 2013, 02:44
  #64 (permalink)  
 
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CONF iture,rudderrudderrat
1. If ATHR is disengaged from ID button thrust needles will catch up with the doghnut where ever they are. To CLB if levers are in CLB. That is why you set it prior to disconnect.
2. If ATHR is disconnected from FCU, thrust will freeze in the present with thrust lock and ECAM warning.
3. If ATHR fails it will freeze with Thrust lock and ECAM.
The FOB in question is very old. ACNav is unable to digest it.
All this will invite another comment from bubbers44. That is his priviledge but it is not possible to conduct type rating through this channel.
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Old 2nd Oct 2013, 13:22
  #65 (permalink)  
 
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Originally Posted by vilas
If ATHR is disconnected from FCU, thrust will freeze in the present with thrust lock and ECAM warning.
Not necessarily, the THRUST LOCK function would not activate when the thrust levers are out of the CL detent.
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Old 2nd Oct 2013, 13:51
  #66 (permalink)  
 
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Vilas,
2. If ATHR is disconnected from FCU, thrust will freeze in the present with thrust lock and ECAM warning.
3. If ATHR fails it will freeze with Thrust lock and ECAM.
Not necessarily, See 22,30,90: Thrust Lock Function

"The Thrust Lock function is activated when the thrust levers are in the CL detent (or the MCT detent with one engine out), and:-
The flight crew pushes the A/THR pb on the FCU, or -
The A/THR disconnects due to a failure.

The thrust is locked at its level prior to disconnection. Moving the thrust levers out of CL or MCT suppresses the thrust lock and gives the flight crew manual control with the thrust levers."

I prefer the FCOM explanation thanks.
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Old 3rd Oct 2013, 02:50
  #67 (permalink)  
 
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CONF iture, RRR
In my reply I had assumed normal position of thrust levers in auto position which is in CLB. However if for some reason the thrust levers are not in CLB while stil in active auto thrust then thrust lock won't activate and thrust will remain at the present position when disconnected.
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Old 3rd Oct 2013, 10:18
  #68 (permalink)  
 
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All this will invite another comment from bubbers44.
Me first. No wonder those beggars over the Atlantic didn't know what was going on... Is that an aeroplane you guys are flying or something the professor in "Back to the Future" made??
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Old 3rd Oct 2013, 12:21
  #69 (permalink)  
 
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Originally Posted by Vilas
However if for some reason the thrust levers are not in CLB while stil in active auto thrust then thrust lock won't activate and thrust will remain at the present position when disconnected.
Not necessarily - Thrust could also increase depending where the THR LVRS have been left.


Originally Posted by Capn Bloggs
Is that an aeroplane you guys are flying or something the professor in "Back to the Future" made??
To get a good and complete knowledge on the A/THR, the system requires a fair amount of regular home work and experiments on the sim or the line.
Nothing like the Boeing you know where the thrust is generally where the thrust lever is ... but was it too simplistic for Airbus ?
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Old 3rd Oct 2013, 21:03
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Just watched Back To The Future again last week. Great flick. You may be right.
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Old 3rd Oct 2013, 21:48
  #71 (permalink)  
 
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Guess I 'll stick to a Boeing.
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Old 4th Oct 2013, 00:11
  #72 (permalink)  
 
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Good choice!
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Old 4th Oct 2013, 02:26
  #73 (permalink)  
 
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I must admit to a bit of misunderstanding regarding AT and bumping it into MCT.
While enroute, I bumped the levers out of CLB and into MCT thinking I'd lose AT as well and I didn't. The EPR started climbing, obviously, and putting them back into the CLB detent returned everything to normal.

It was as dramatic a shift in automation levels - more of a hybrid change! but it was easily returned to the previous level.

Always learning on the Bus.
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Old 4th Oct 2013, 13:31
  #74 (permalink)  
 
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Originally Posted by Altcrznav
Always learning on the Bus.
Exactly - A lot to be learned and practiced to not forget - Already not easy for us flying the thing to understand and remember everything, so I am at lost when some with NO experience on the bus or even on a flight deck show up and pretend to explain how works the A/THR ...
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Old 4th Oct 2013, 20:46
  #75 (permalink)  
 
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For the record, I was working off an old set of notes which were possibly incomplete - they didn't mention the CL/MCT detent in combination with the FCU A/THR button. I made a mistake, I put my hands up to it - no big deal.

So correct procedure has the pilot match the "doughnut" to the current thrust level before using the instinctive disconnect button - doesn't seem particularly onerous to me. The FCU button allows for a way to manually ensure that Thrust Lock mode is activated, which seems like a sensible thing to provide.
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Old 5th Oct 2013, 00:52
  #76 (permalink)  
 
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Originally Posted by dozy
For the record, I was working off an old set of notes which were possibly incomplete
As you obviously don't have the tools, no more the knowledge or the experience to comment on how is working the A/THR on the bus, just quit on doing it. You create more disinfo than anything else.

The FCU button allows for a way to manually ensure that Thrust Lock mode is activated, which seems like a sensible thing to provide.
Another piece of your disinfo as no one is looking forward to activate the Thrust Lock function. That's something you want to suppress, not to activate.
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Old 5th Oct 2013, 01:02
  #77 (permalink)  
 
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Originally Posted by CONF iture View Post
Another piece of your disinfo as no one is looking forward to activate the Thrust Lock function. That's something you want to suppress, not to activate.
Oh really?

Originally Posted by CONF iture View Post
We use [the FCU A/THR button] every time we want to arm or activate again the A/THR following a voluntary disconnection. No ABNORMAL situation involved.
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Old 5th Oct 2013, 01:29
  #78 (permalink)  
 
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Dozy, you're so confused in your 'knowledge' that you don't even realize the difference between engaging the A/THR and activating the Thrust Lock function
Keep showing your ignorance on this specific subject at your own pace.
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Old 5th Oct 2013, 01:40
  #79 (permalink)  
 
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As you yourself say, disengaging A/THR using the FCU button with the thrust lever in the CL or MCT detent will trigger the Thrust Lock function, and in that post you claimed to use the FCU panel button "all the time". So if engaging Thrust Lock is to be avoided, why would you do that rather than use the "instinctive disconnect" buttons?
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Old 5th Oct 2013, 01:53
  #80 (permalink)  
 
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Originally Posted by dozy
As you yourself say, disengaging A/THR using the FCU button with the thrust lever in the CL or MCT detent will trigger the Thrust Lock function, and in that post you claimed to use the FCU panel button "all the time". So if engaging Thrust Lock is to be avoided, why would you do that rather than use the "instinctive disconnect" buttons?
Exact same reply for you dozy.
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