View Full Version : What happens.... ... in A320 ?

9th Jun 2007, 20:44
Note : In an automatic landing, the system generates a "RETARD" callout at 10 feet radioaltitude (RA), which prompts the pilot to move the thrust levers to IDLE in order to confirm thrust reduction

Always appreciate all you guys kind replies.....

While reading FCOM, ... What happens if I do not set THRUST idle in
AUTO LANDing even after touchdown ????

Tight Slot
9th Jun 2007, 20:45
Still lands ok but then you won't be able to pull reverse on the roll out

9th Jun 2007, 21:04
You will want to fasten your seatbelt and harness VERY tight.. going off the end of the runway around 140kts is not going to be fun.

9th Jun 2007, 21:34
Hi...if memory serves correctly..if you do not retard the thrust levers at the 'RETARD'call..the FMS will command the A/THRUST to maintain Vref+wind correction..as you try to flare the aircraft for landing,the thrust will increase to maintain speed resulting in a mess you do not need at this stage

Henry VIII
9th Jun 2007, 21:40
My memories say that the ATHR set idle thrust regardless of the position of thrust levers.
BUT... without thrust levers zeroed the spoilers will not deploy automatically... and without spoilers deployed autobrakes will not be activated.
So you land perfectly, but without autobrakes !

Take care :ok:

9th Jun 2007, 22:53
I'm surprised a Fairy can read AND write. :E

9th Jun 2007, 22:54
I always thought it was a statement not a command callout.


9th Jun 2007, 23:11
The callout is a reminder - it is to say that you should have retarded the thrust levers by now - you dullard !
Here we get into engine differences.
V2500 - loads of residual thrust, different flap setting, tends to float :uhoh:
CFM, little residual thrust, power comes off briskly, autolands much better :ok:
So......... V2500 be careful, CFM - relax, it won't be a problem !

9th Jun 2007, 23:15
RETARD is neither a statement nor a command, it's a reminder.

In autoland, the A/THRUST will automatically command idle at FLARE, whether you retard the thrustlevers or not. However, in this case the A/T won't disconnect, so if you press the disconnect buttons with the thrust levers still in CL detent, you'll have some fun!

10th Jun 2007, 00:15
I disagree. During an autoland the RETARD callout at 10'RA is very much a command. The thrust should have already started to reduce to idle from around 30'RA and IDLE should annunciate on the FMA from 30'RA. Think about a CATIIIB autoland with no DH (no visual references required), you have no visual cue when to retard. It is a totally automated approach and the system is telling you when to retard in preparation for the autobraking following touchdown

Some confusion can exist when executing a non-autoland (manual) landing without both autopilots engaged. Here the RETARD call is at 20'RA and is more of a reminder and not a command. Depending on your speed they may have already been brought back to idle as this prompt is made.

During autoland if the THR LVRS are not brought back the aircraft will land just fine and at idle thrust, but as Henry VIII says with no spoilers and therefore no autobrakes. Manual braking without spoilers would work OK although I would never want to try this theory.

Dream Land
10th Jun 2007, 02:46
Here the RETARD call is at 20'RA and is more of a reminder and not a command. Depending on your speed they may have already been brought back to idle as this prompt is made.
Actually 10 ft as mentioned by SRover40.

Dan Winterland
10th Jun 2007, 05:44
From FCOM 1.22.30 p65:

'The RETARD mode is only available during automatic landing (AP engaged in LAND mode). At approximately 40' RA, the RETARD mode engages and remains engaged after touchdown. The A/THR commands IDLE thrust during the flare, and the FMA and enginge warning display IDLE. If the autopilot is disengaged during the flare before touchdown, the speed mode replaces the RETARD mode and the plot has to manually reduce thrust.

Note: In an automatic landing, the system generats a RETARD callout at 10' RA which prompts the pilot to move the thrust levers to IDLE in order to confirm thrust reduction. In a manual landing conditions, the system generates this callout at 20' RA as a reminder.'

Dream Land
10th Jun 2007, 05:54
Kite, sorry, I now see that you were referring correctly to a manual landing, apologies.

10th Jun 2007, 12:13
Is that what that callout means? I thought it was some sort of new fangled Airbus wizardry which automatically called the B1 engineer out of the crewroom to do the turnround
At the company I am currently with the B2 staff attend the transits. B1 called for serious defects only.

10th Jun 2007, 13:35
We've got most of it I think. With 'Land' annunciated and an A/P in, the FMGC will command the thrust to Idle and 'Thr Idle' will be annunciated on the FMA. A 'Retard' calll will be made as a reminder at 10' Radalt. If you don't, it will keep shouting 'Retard' at you (with some justification), there will be no spoiler deployment and therefore no Autobrake and, as someone said earlier, you had better tighten your harness because the speed will stabilise at about 100KIAS (A319) and you are going ploughing!!

Cheers all,