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320p
6th Mar 2008, 14:45
Hi

Incase of overweight landing,QRH shows that,"In all cases,if landing configuration is different from FLAP FULL,use 1+F for go around"

Any particular reason for this being different from normal Go Around procedure ?

Thanks

Bruce Waddington
6th Mar 2008, 18:41
Hello 320P

The following is from our QRH checklist for overweight landing.

"– FULL is preferred for optimized landing performance.


If the aircraft weight is above the maximum weight for landing in CONF FULL (given in the table below), use CONF 3 for landing.

In all cases, if landing configuration is different from CONF FULL, use
CONF 1+F for go-around (select FLAP lever to 1). This will ensure the required go-around performance is achieved."

So, it's all about the go-around performance . If you are under the max weight for flap FULL then the go-around performance considerations will be met in Config 3. If you are over that weight you must go to Flap 1 to ensure the go-around performance considerations are met.

best regards,

Bruce Waddington

Slasher
7th Mar 2008, 10:51
Question for ya Brucie! :E

Why is it 1+F after a GA and not just 1 (ie less the 'F' bit),
considerin that when Config 1 is selected from clean, theres
no F.

I mean why does Airboos have a configuration diference with
the clean-to-Flap 1 goose as compared to the GA gander? :confused:

WaterMeths
7th Mar 2008, 11:41
Yep

In the go-around case the speed has been below 210 knots and so the config will be 1+F.

The logic is that the 1+F is not available in flight unless flaps 2,3 or FULL has been selected previously.

Cheers

WM

Bruce Waddington
7th Mar 2008, 19:38
Hi Slasher,

Good question !

I 'suspect' (read don't know for sure) that the reason for only giving you Slat 1 in Config 1 on the approach is that you can extend the slats 15 kts sooner on a 319/320 and 10 kts sooner on the 321 than if the Config 1 selection gave you 1+F.

And of course this drops the Vls and lets you get the speedbrakes out sooner if you need them. :-))

best regards,

Bruce Waddington

edited to remove superfluous stuff

320p
8th Mar 2008, 07:39
Hi Bruce

Like you mentioned it would be related to go- around performance,however My FCOM 3 and QRH does not specifically mention "This will ensure the required go-around performance is achieved".

This doubt basically related to the relative angular deflection of flap/slat.
From Config 3 to 2,Slat does not move(and only flaps move).Wouldn.t that be preferable initially at high GW. vis a vis Config 3 to 1 where in both Flaps and Slat move.

Thanks

Clandestino
8th Mar 2008, 21:53
A320 will never be approach climb gradient limited in config2 overweight G/A.

But 321 sometimes will and therefore require 1+F for go-around.

To keep it on the safe side, Airbus made 1+F overweight go-around procedure mandatory across entire rage of its narrowbodies.

Source: my training manual.

It's a bit unnerving to move flaps from 3 to 1 and suddenly see Vls move above your current speed but, with both donkeys alive and kicking, you quickly get above it (at least in the sim).

Bruce Waddington
9th Mar 2008, 05:00
Clandestino,

You write, "Source: my training manual.'

Would that be your company training manual or the Airbus Flight Crew Training Manual ?

Could you please post the applicable section ?

best regards,

Bruce

212man
9th Mar 2008, 05:43
This is from the Cathay 30/340 FCTM (They might want to add leaving the gear down, in case it's considered a fly past :E)

Automatic landing has been demonstrated up to the weights specified in FCOM 3.01.32. CONF FULL is the preferred landing configuration provided that the approach climb gradient criteria can be achieved using CONF 3 for the go-around. At high weights and temperatures, a CONF 3 approach is required to satisfy go-around criteria (QRH Maximum Weight For Go-Around in CONF 3 table refers). In all cases, if the landing configuration is different from CONF FULL, select Flaps 1 (CONF 1+F) at initiation of the go-around. The approach climb gradient criteria is never limiting in CONF 1+F. To ensure that maximum thrust is available in the event of a go-around, select the packs off, or use the APU as the bleed source.
If a go-around is performed using CONF 1+F, VLS CONF 1+F may be higher than VLS CONF 3 + 5 kt (VAPP). In this case, follow the SRS order, which will accelerate the aircraft up to the displayed VLS. VLS CONF 1 +F equates to 1.23 VS1g whereas the minimum speed for go-around required by regulation is 1.13VS1g. Consequently, this requirement is always satisfied.

Clandestino
9th Mar 2008, 22:16
Bruce, this is from company's training manual, though parts of it might be copy-pasted from AB's. I'll post it when I dig it out, but AFAIR it's quite similar to the one posted by 212 man.

Cityliner
9th Mar 2008, 23:02
It is just to standardise the A320 Fam operation!
Flaps one is mandatory on the A321 when performing a Go around above MLAW!
Reason is the Climb Gradient