Retard-Throttel back to idle?
Thread Starter
Joined: Oct 2007
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From: In OY-VKH
Retard-Throttel back to idle?
Hi,
When landing the bus and on final ,of course you hear the GPWS
and (50ft?) before touchdown the ''retard'' sound is going on...
So this 'retard'' means that you must power back to idle before touchdown
to make a good touchdown?
Sorry for my comfusing , but want to be sure
//Robin
When landing the bus and on final ,of course you hear the GPWS
and (50ft?) before touchdown the ''retard'' sound is going on...
So this 'retard'' means that you must power back to idle before touchdown
to make a good touchdown?
Sorry for my comfusing , but want to be sure
//Robin
Joined: May 2005
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From: All over the place
Robini
I have been taught that "retard" call out on normal approach is a guidance call out (a reminder), in reality if you dont at least begin to retard power you will end up floating down the runway past the touch down point, as the autothrust will come in and try to maintain Vapp. It is different if it is an autoland, in this case the retard call out is an instruction. And yes i am currently flying an Airbus. Hope this helps.
Regards, Mondeoman
Regards, Mondeoman
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From: Miami
Mondeoman:
You are half right, indeed the RETARD auto-callout is a reminder that you should be at idle by the time you hear it.
The most important thing to know is as you said, that auto-thrust will be active and chasing the target speed (either selected or managed) until the thust levers are manually selected to idle; even if you are flaring, this will lead to unwanted acceleration and power increase. Pilots are supposed to use the same airmanship as any other airplane to retard the thrust levers, not wait for instructions.
Where you are wrong is that the same applies to auto landings retard is not an order it is a reminder that you should be at idle, only with the added protection that the power will automatically come to idle if the thrust levers are not retarded.
barke:
It doesn't work this way on Airbus FBW because of the logic of the auto thrust, you must bring the thrust levers to idle for touch down, otherwise the speed will increase during your flare to maintain selected or managed speed.
G
You are half right, indeed the RETARD auto-callout is a reminder that you should be at idle by the time you hear it.
The most important thing to know is as you said, that auto-thrust will be active and chasing the target speed (either selected or managed) until the thust levers are manually selected to idle; even if you are flaring, this will lead to unwanted acceleration and power increase. Pilots are supposed to use the same airmanship as any other airplane to retard the thrust levers, not wait for instructions.
Where you are wrong is that the same applies to auto landings retard is not an order it is a reminder that you should be at idle, only with the added protection that the power will automatically come to idle if the thrust levers are not retarded.
barke:
It doesn't work this way on Airbus FBW because of the logic of the auto thrust, you must bring the thrust levers to idle for touch down, otherwise the speed will increase during your flare to maintain selected or managed speed.
G
Joined: Feb 2005
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From: flyover country USA
One of the first lessons a pilot learns (or should learn) is: To climb, increase throttle. To descend, reduce throttle. It's so obvious to an experienced pilot that we forget to spell it out to the newcomer. 
The Cooler King
Joined: Feb 2004
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From: Europe
Assuming our Swedish based friend is using a flightsim, why bombard the poor kid with data that he won't need for another few years yet.
In short, the answer is "Yes" put the throttles to IDLE mate!
In short, the answer is "Yes" put the throttles to IDLE mate!
Joined: Apr 2002
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From: Put out to graze
Visual approach/landing:
You shouldn't hear the RETARD - if you do it is to tell you that you should of selected idle power. I select idle at 30ft and never hear RETARD. Works well. If it is not done by 20ft then you get RETARD. It is a reminder to allow speed to decrease below Vapp and not go into speed reversionary mode at the flare!!
Automatic landing:
You do hear the retard call at 20ft, it is an instruction. The engines have already commanded THR IDLE by now but for same reasons as above, you have to physically select Thrust Levers to IDLE.
Remember on the 'bus, the TL's are switches not throttles connected by cables to the donks.
You shouldn't hear the RETARD - if you do it is to tell you that you should of selected idle power. I select idle at 30ft and never hear RETARD. Works well. If it is not done by 20ft then you get RETARD. It is a reminder to allow speed to decrease below Vapp and not go into speed reversionary mode at the flare!!
Automatic landing:
You do hear the retard call at 20ft, it is an instruction. The engines have already commanded THR IDLE by now but for same reasons as above, you have to physically select Thrust Levers to IDLE.
Remember on the 'bus, the TL's are switches not throttles connected by cables to the donks.
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From: Planet Earth
You shouldn't hear the RETARD
Please allow me to disagree with your generalized statement, there is no one way to do things, what works for you may not work in all situations. On a regular basis I operate with substantial tail winds, now add to that an A321 at 74 tones, chopping the power above 30 FT is not an option.
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From: Hong Kong
when you close the throttles to IDLE after the RETARD call-out, does this automatically deactivate the Autothrust?
does the RETARD call still come if you are manually controlling thrust during final approach? or will it come nonetheless, due to the GPWS?
does the RETARD call still come if you are manually controlling thrust during final approach? or will it come nonetheless, due to the GPWS?
Joined: Apr 2002
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From: Put out to graze
does the RETARD call still come if you are manually controlling thrust during final approach? or will it come nonetheless, due to the GPWS?
Dream land, fair point although you have rather dramatised my statement by saying 'chopping the power above 30ft is not an option'; not quite what I said, eh?
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From: Planet Earth
kick the tires, sorry to put words in your mouth, just don't want anyone to do anything automatically at a certain height, weight, wind conditions, and density altitude play a big role. Happy landings, D.L.