I’ve been travelling to Vietnam a few times a year over the last few years, and I’ve always noticed that on all my domestic flights (A320s and (A321s) the flaps are retracted to only their takeoff position at the conclusion of the previous flight. I haven’t noticed this anywhere else in the world. Does anyone have any insights as to why this is the case? Does it really save that much time for the next flight?

What was the temperature outside? If it's hot (30C - 40C depending on operator) the crew will not fully retract the slats in order to prevent errant air bleed fault messages.

Airbus SOP to have flaps at 1 above 30 deg C

Definitely always over 30 outside. Thanks for the answers!

That's interesting as I can think of countless times this wasn't followed. AA in PHX all summer long comes to mind.

Is this up to the carrier to follow?

I would think this must be a preferred technique as opposed to SOP.

barney captain wrote:

That's interesting as I can think of countless times this wasn't followed. AA in PHX all summer long comes to mind.

Is this up to the carrier to follow?

I would think this must be a preferred technique as opposed to SOP.

It's in the normal standard operating procedures for after landing, but the relevant passage says "may", not "shall" or "must", so I suppose you are correct in calling it "preferred technique".

"On ground, hot weather conditions may cause overheating to be detected around the bleed ducts in the wings, resulting in “AIR L (R) WING LEAK” warnings. Such warnings may be avoided during transit by keeping slats in CONF 1, when OAT is above 30 °C."

barney captain wrote:

That's interesting as I can think of countless times this wasn't followed. AA in PHX all summer long comes to mind.

Is this up to the carrier to follow?

I would think this must be a preferred technique as opposed to SOP.

Yes it is up to the carrier, it may result in higher maintenance costs if not followed.

zeke wrote:

Yes it is up to the carrier, it may result in higher maintenance costs if not followed.

And yet AA does not do it (at least in PHX) and nor did US before them. US operated the single largest Airbus fleet in the world when they merged with AA. There are few, if any, carriers in the world who know more about the operation of the Airbus A320 family than AA. And they do not follow this recommendation.

And now I am curious as to why that is. Aren't you?

DocLightning wrote:

zeke wrote:

Yes it is up to the carrier, it may result in higher maintenance costs if not followed.

And yet AA does not do it (at least in PHX) and nor did US before them. US operated the single largest Airbus fleet in the world when they merged with AA. There are few, if any, carriers in the world who know more about the operation of the Airbus A320 family than AA. And they do not follow this recommendation.

And now I am curious as to why that is. Aren't you?

That's interesting - all three airlines that I've worked for so far follow this procedure (you have one or two Captains that think they know better, but that is non standard)...I never encountered the bleed leak message but I guess it would happen once in a while if we didn't follow this procedure...
Maybe the reason is related to ground handling though. Some fuel truck drivers refuse to connect if the flaps are not retracted (I guess they are worried about hitting the extended Slats while positioning themselves under/near the wing) - in this case we just fire up the hydraulics again and retract the flaps...

Interesting indeed. I've seen many airlines of various nationalities follow that procedure in various parts of the world - but can't think of one US carrier I've seen do it.

I always assumed it was just a technique of saving a full cycle on the flaps by retracting them to the take-off setting (usually One I believe).

We used to leave the flaps at flaps 1 when the oat was >30c. Then after an aircraft mod was installed to the entire fleet our procedure was changed to leave the flaps at flaps 1 when the oat is >40c.

I remember the flaps being in conf 1 after landing being not an uncommon occurrence. Since the change it was rare for us to leave the flaps in conf 1 after landing.

Perhaps humidity plays a factor in the VN vs AA manual... Vietnam being hot and humid while PHX is hot and dry?

So, in effect, the temp probes think the anti-icing is on when it's not? And by dropping slats etc to first stage it gives the probes a bit of a breeze?

Not that anti-icing is on, but to prevent the two Bleed Monitoring Computers from thinking there is a bleed leak.

DocLightning wrote:

zeke wrote:

Yes it is up to the carrier, it may result in higher maintenance costs if not followed.

And yet AA does not do it (at least in PHX) and nor did US before them. US operated the single largest Airbus fleet in the world when they merged with AA. There are few, if any, carriers in the world who know more about the operation of the Airbus A320 family than AA. And they do not follow this recommendation.

And now I am curious as to why that is. Aren't you?

Well, Doc, I've never questioned your sanity before, and I'm not about to now. But I can definitely tell you I've seen this done by AA at PHX more times than I could count, and US/HP before them.
You could, the last time I was through there some time ago, see dozens of A319s and A320s lined up at the terminal with slats down.

I understand there's been a mod (as there should be... poor Fifi A320s, can't handle warm climates without their fire bells going off? For shame!), and this may not be necessary any more.

AA737-823 wrote:

Well, Doc, I've never questioned your sanity before, and I'm not about to now.

That makes me want to question your sanity.

AA737-823 wrote:

But I can definitely tell you I've seen this done by AA at PHX more times than I could count, and US/HP before them.
You could, the last time I was through there some time ago, see dozens of A319s and A320s lined up at the terminal with slats down.

Perhaps you're right. Living near SFO and OAK, there's rarely a reason for me to fly to PHX unless I am visiting my uncle.