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air_cowboy
22nd May 2009, 05:33
what is the best technique for Flap 3 landings on the A320?

Is tailstrike probability increased?

Robini
24th May 2009, 10:00
First of all A320 isn't a plane you normaly should be worried about when it comes
to tailstrike. Bigger bus models may have that ''problem'' but only when takeoff or landing at farely high speeds.

Flaps increase doesn't make that the chanses of tailstrike getting higher, just to increase
the lift coefficient - and thereby possible to land at lower speeds.

In this case when Flaps 3 landings are not so often used as Flaps full you may just keep a higher speed to not stall it. But of course airplanes at higher speeds is much moore controlable than the planes att low speeds, be careful to not overpull it.

FlyUK
24th May 2009, 10:11
Sorry Robini, totally disagree.

Flap3 on the 320 makes a HUGE difference to the pitch attitude at landing. The Vref increase is about 4 knots, but you will have about 7ish degrees nose up as opposed to 4 in flap full. Personally don't find it as stable on the approach, but company SOP is F3 unless F full is required.

The 320 IS much more of an issue in the flare with F3 than the 321 in F3. Don't try to hold it off. I find closing the thrust levers at 25R and a tiny little flare about 15R will see you right. If you use a Flap full flare with F3 you will float along at 8 feet! :ok:

Iceman49
24th May 2009, 17:30
FlyUK, is the F3 SOP for fuel consevation, and if so, what sort of fuel savings do you realize? Thanks.

guiones
24th May 2009, 19:28
Robini:

Refrain from such ignorant posts, read and learn from experienced pilots. Anyone that has been even close to an A320 series A/C knows you got everything backwards; have a little respect for yourself and stick to what you really know, if any in aviation from your posts.

G

Max Angle
24th May 2009, 20:45
what sort of fuel savings do you realize? Thanks

We were told it is about 7kg a sector, our lot looked at it and decided it was not worth doing when you took account of perhaps a few more go-arounds due not stable and the increased tail strike risk.

Zippy Monster
24th May 2009, 20:56
I fly the 319 and to be honest, my technique isn't much different whether using Flap 3 or full. The only difference I find is the slightly higher nose attitude and the fact the aeroplane feels a little more "slippery", so to speak.

In terms of flare, I still close the thrust levers around the same point, i.e. around the "30" auto call-out (plus or minus a bit depending on head/tailwind conditions of the day); for Flap 3 I find I flare ever so slightly later and obviously a little bit less due to the attitude already being higher. Other than that, I find there's little difference between the two.

I can't really speak for the A320 or 321 but with the higher weight I suspect there might be a bit of a difference? I note the poster above who mentions the huge difference in attitude between F3 and F full on the A320.

Lemurian
25th May 2009, 12:37
The 320 IS much more of an issue in the flare with F3 than the 321 in F3. Don't try to hold it off. I find closing the thrust levers at 25R and a tiny little flare about 15R will see you right. If you use a Flap full flare with F3 you will float along at 8 feet!
That's also my experience.
As a matter of fact, the A321 wing trailing edge is different from the rest of the family -Airbus has added a few inches to the chord, therefore on the flap dimensions. The result is a somewhat "flatter" attitude during the approach than on a 320.

martuus
28th May 2009, 12:18
In my company, there are 3 of A320s and 7 of A319s, I did not often use Flap 3 landing unless appllied noise restriction in BKK airport.
Pesonel Tech. is little late in thrust reduction ( thrust is not much to keep Vapp ) and my flare is changing pitch not as much as Flap full ( attitude already high so margin for tail strike is not much ).
Every time I do Flap 3 landing, I have to prepare my configuration earlier than Flap full coz' speed not reduce nicely when do ILS Decel. App.

Jimmy Do Little
29th May 2009, 17:03
what sort of fuel savings do you realize? it's closer to 75 kgs saved per landing.

Meikleour
29th May 2009, 19:34
On the CFM A319 that I fly the stabilised Flap FULL/Vapp total fuel flow is normally 30-32kgs/min. and Flap3/Vapp gives 26-28kgs/min.

With decellerated approach techniques normally one is only fully spooled up from 1000ft. AAL. - so the question remains - where does your 75kgs /landing come from?!!

Max Angle
29th May 2009, 23:03
Those figures tie in very nicely with the 7-8kg that our tech. guys worked out we would save, 75kgs is complete nonsense.

PantLoad
30th May 2009, 13:50
Please refer to QRH 2.18A....Unreliable Speed Indication / ADR Check Proc

This will give you a pretty good idea of pitch angles on approach. Figure
adding four degrees for a nice flare, and I think you'll find, with wings level, you still have almost 2 degrees to spare (assuming struts compressed....struts extended, you have almost 4 degrees to spare).
FCOM 3.03.22 P3 shows how these margins are reduced with increased bank angle.

In theory, you can scrape metal with FLAPS 3, a significant bank angle at touchdown, and improper flare. However, by following
SOP, a FLAPS 3 landing should not force a meeting and subsequent carpet dance in the chief pilot's office.

Fly safe,

PantLoad

dartagnan
30th May 2009, 16:00
but company SOP is F3 unless F full is required.
these companies will be sued if accident happen. Normal configuration is Full flaps for landing.

SOP must be full flaps unless F3 is required. that's the correct procedure. Not the reverse. I think some airlines think they save money, less flaps=less drag=less fuel...

ok, but you get less lift=more power to get same amount of lift=more fuel

I doubt you save money with F3.

same thing with N1 taxi to your gate:

1 engine taxi =less power= less fuel(airline thinking!)
ok,...but 1 engine=more power on the engine=more rudder and steering to turn due to asymmetric thrust = more fuel(airbus thinking)....

conclusion: to save real money, follow airbus procedures:ok:.
if an airline was saving money with their "new" procedure, all airlines would do the same.
They don't, so when I hear of a new SOP procedure, we can just laugh at it!

guiones
30th May 2009, 21:51
Dartagnan:

Flap 3 landing and 1 engine taxi ARE Airbus procedures.

The option exists for the operator and Capt and it is on the FCOM's.

1 engine taxi is not only fuel savings, but also brakes and engine life.

G

TyroPicard
31st May 2009, 10:03
dartagnan..
I think some airlines think they save money, less flaps=less drag=less fuel...
Correct..
ok, but you get less lift=more power to get same amount of lift=more fuel
Complete rubbish!