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Robini
5th May 2008, 13:20
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

Dream Land
5th May 2008, 13:31
Doesn't MS come with directions? :E

wileydog3
5th May 2008, 13:32
It is simply a voice command and you can follow it or not. It is not necessary to be in idle at touchdown but if properly configured, etc, it makes sense.

boofhead
5th May 2008, 16:17
I thought it was a comment on the pilots' intelligence?

dixi188
5th May 2008, 17:50
It is important to have the throttles (Power Levers) at idle on touchdown so that the Ground Spoilers will deploy. Also so that Reverse can be selected.
Hope this helps.

forget
7th May 2008, 11:53
Robini

Join Date: Oct 2007
Location: Gothenburg,Sweden
Age: 15
Posts: 73

Reasonable question. :) Deserves reasonable answers.

Mondeoman
7th May 2008, 12:44
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 :)

guiones
7th May 2008, 13:01
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

barit1
8th May 2008, 00:16
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. :ouch:

Pilot Pete
8th May 2008, 08:11
I think you will find there are slightly more force vectors involved, which don't necessarily mean your statement is completely true.;)

PP

Farrell
8th May 2008, 08:39
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!

ironbutt57
8th May 2008, 09:12
Thrust Levers..to idle

kick the tires
8th May 2008, 09:45
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.

Dream Land
8th May 2008, 10:06
You shouldn't hear the RETARD :eek: 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.

holdmetight
8th May 2008, 13:32
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?

FLX/MCT
8th May 2008, 13:47
A/T always disconnects when you pull the levers to idle...

"Retard" sounds independently of the A/T status. It starts 20ft RA during a manual landing and at 10ft RA during landing with AP

student88
8th May 2008, 14:36
FLX/MCT, quite possibly the youngest Airbus pilot ever! :ok:

FLEX/MCT
8th May 2008, 15:38
Dammit I spend ages thinking of a cool Airbus related username and choose one that some 16 year old kid has used first!!! Looks like I am the RETARD now.

F/M

kick the tires
8th May 2008, 16:20
does the RETARD call still come if you are manually controlling thrust during final approach? or will it come nonetheless, due to the GPWS?

RETARD has absolutley nothing to do with GPWS or EGPWS.


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? :=

Dream Land
8th May 2008, 16:41
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.

potkettleblack
8th May 2008, 19:40
Robini there are a couple of fundamental reasons for the "retard" auto callout on the Airbus.

Firstly it comes down to the whole philosophy of the airbus FBW series. When we take off the thrust levers are moved from the idle (or slightly ahead of this if taxiing under power) into either the TOGA or FLX detents. TOGA gives you all the available thrust for take off although is not used that often. FLX is used in order to reduce engine wear. Once airborne and passing your thrust reduction altitude which is usually around 1500agl then the thrust levers are manually moved from TOGA or FLX back into the CLB detent. The autothrust will be active by now and will manage the required thrust settings based on pilot inputs. The important point to note here is that you DO NOT touch the thrust levers again until landing. The thrust levers also DO NOT move in flight, they remain in the same position unlike on boeing aircraft where they will be moving and provide a visual clue that some pilots like to see to get a "feel" for what the aircraft is doing. Therefore the retard callout is a reminder that you need to pull the thrust levers back to idle and more than likely select an amount of reverse thrust - can be idle or full as required.

Secondly, as has been well described if you do not take the thrust levers back to the idle detent then the autothrust will chase your speed and the autobrakes and ground spoilers will not deploy. This has been shown with tragic results in the recent TAM accident.

In summary if you are in a stablised approach then our FCOM's say to flare at 30' and the auto callout will come in at 20'. The flare is no different to flying a small aircraft with the pilot looking out the window far ahead down the runway judging the flare height, using your peripheral vision to give you a cue and using the autocallouts as further guidance. Of course autolands are different but I won't go into those as it will confuse matters.

Hope this helps.

FLX/MCT
8th May 2008, 21:34
Well.... I wish I was a pilot yet. But what not is will become, I hope, student88!

Oh FLEX/MCT you have a really cool username:}. Let's say my one contains a spelling mistake (the missing "E" in flex) so that your's is better. But pleeeease don't call me a kid, although the age where I might wish to be called a kid might come faster than I am able to think now :O

blablabla
8th May 2008, 22:27
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. :ouch:

This is exactly the way not to fly an aircraft if your taught by somebody who knows what they are talking about. In order to climb in my aircraft i`ll pull or move the control colum backwards and in order to descend i move the control colum forward.
I use the thrust levers to control and maintain the desired speed.

Are you one of those yanky doodle dandy crop dusting pilots who when they get below the glide on an ILS crank the Thrust levers forward to balloon back up onto the glide and when your speed drops you push the nose of the aircraft down to regain the correct speed.....absolute amatuer

WindSheer
8th May 2008, 22:56
I am not an airbus pilot...

But I was always under the impression that once the a/c has left approach mode and gone into land mode, the engines will idle automatically regardless of whether the levers are 'in or out'???
I was also under the assumption that the a/c will go through the autoland motions on the PFD whether the autopilot is in or not...hence thrust idle at 30ish feet?

I could be talkin out of my bum cheeks though!!

Captain Marvel
8th May 2008, 23:57
Windsheer,

On the A330, RETARD mode is only automatic with an autoland. It commands Iidle thrust during the flare (from 40'RA). The "RETARD" callout comes at 10'RA and is an order to close the thrust levers to confirm thrust reduction.

When manually flying, the callout is a reminder at 20'RA, thrust will not automatically retard.

The FCOM is clear on the sequence, in an autoland, check the FMA/ATHR for IDLE at approx 30'RA and after the "RETARD" callout at 10'RA, move the levers to idle.

In a manual landing, at 20'RA, move the levers to idle if not already done.

CONF iture
9th May 2008, 00:37
I thought after a few reminders, 2 or 3 (?) the guy was talking louder … !?
It does not look so (from 2:10 in that nice video (http://www.youtube.com/watch?v=TgquZ5_A5t0))

… About 2000 feet runway … left behind, but what a kiss Boss !


On the side, some pretend following PF inputs through that little nervous Side Stick Indicator … Not for me, no thank you.

Golf Alpha Whisky
9th May 2008, 14:59
Potkettleblack - thank you for an informative and educational answer without the need for sarcasm. :ok: