PDA

View Full Version : A320 flaps 2 retracting to flaps 1+f for holding


Orange future
22nd Nov 2016, 00:37
Apparently some guys in our outfit arrive in the hold clean, select flaps 1 then 2 then retract to flaps 1+f in order to hold with a reduced deck angle.

I kinda like not doing things in the bus unless fcom specifically permits it.

Can anybody see any pitfalls in this practice?

khorton
22nd Nov 2016, 00:51
The extended flaps will have higher drag and thus require higher fuel flow. Which published data are they using to determine the expected fuel flow in the hold? Are these guys carrying more holding fuel than everyone else?

Lantirn
22nd Nov 2016, 02:20
Some guys like to do whatever comes to their head. It's amazing in an industry like aviation with SOPs and some will find their way to do something new. I think it's human nature. More fuel burn and one day he'll need it. But I know , he takes also some tons of extra fuel without a single reason, it's safer. I know this character. Those 30 mins are calculated with conf 1.

Common sense means common sense but, what a disaster for a pilot which is born without perception. Even more, without willing to listen...Oh la la

vilas
22nd Nov 2016, 02:28
You are right in not following non standard procedure.In Conf1+F Flap lowers body angle for lift off but in air it saves fuel by giving you only slat in flap1. By trying to hold in F+1 they defeat the smart design of airbus. Company should pull them up for wasting fuel.

Sidestick_n_Rudder
22nd Nov 2016, 07:24
Why use flaps for holding at all? The only reason I see is if max hold speed is higher than minimum clea. Rather unlikely in A320. Heavy A321, or A333 - maybe

misd-agin
22nd Nov 2016, 13:18
Flaps out? Normally you're fast enough to hold clean.
And flaps out holding if there were icing conditions is a bad idea.

PENKO
22nd Nov 2016, 13:51
Apparently some guys in our outfit arrive in the hold clean, select flaps 1 then 2 then retract to flaps 1+f in order to hold with a reduced deck angle.
Who cares about the deck angle?
I have been a passenger in countless holds and not once, not once did I think 'geez, what's up with the deck angle'.
Or is there something else wrong with the deck angle?

Lantirn
22nd Nov 2016, 14:42
Like some guys get hysterical with the expedite button as I clean up and I anticipate course reversal from ATC. It's funny they prefer to select speed even if it's gonna be green dot.

"What's wrong with the pitch", love it.

As one of my fav TRE says, some have to seriously consider changing job. It's too stressy for them. 😂

Nick 1
22nd Nov 2016, 15:01
Cabin of modern lo-co are so packed that , even going vertical , no one will notice any deck angle change .....

Fursty Ferret
22nd Nov 2016, 15:57
Those 30 mins are calculated with conf 1.

Are they? ;-)

Lantirn
22nd Nov 2016, 17:17
I don't know if you fly CFM, but for IAE yes.

Reference DSC 22 20 50 10 28

EGPFlyer
22nd Nov 2016, 18:25
Its calculated at CONF 1 in our CFM A320s as well.

PENKO
22nd Nov 2016, 19:03
But your legal flight plan fuel final reserve figure is not.

Chris Scott
22nd Nov 2016, 19:07
Quote from Sidestick_n_Rudder:
"Why use flaps for holding at all? The only reason I see is if max hold speed is higher than minimum clea[n]."

Think you meant "if minimum-clean is higher than maximum holding speed"?

Quote from PENKO:
"Who cares about the deck angle?"

A non-event when seated. But, at the end of a flight, the cabin crew might find the holding pitch with Flaps 1 (slats only) of about +8 degrees tiresome when using trolleys to clear the meal service, or whatever. Possibly worth a mention to the SCCM?

PENKO
22nd Nov 2016, 19:16
Fair point Chris, but usually any meal service should be long finished by the time you enter the hold. There are just too many pitfalls of flying around with flaps and slats extended (icing and G-load limitations, screw up factor, fuel penalty etc.) to justify a slightly shallower deck angle.

hikoushi
22nd Nov 2016, 19:48
One time had a CA brief me on the fly that he wanted to slow down and select this configuration. This was in the 330 on a (VERY) long final approach to PEK while level at intercept altitude (been a while, don't remember what the altitudes / meters whatever are over there but it was for the center runway, 36R IIRC). First I had heard of the technique so just asked "why?" and he said "want to slow down to stay below 210 but keep a lower deck angle". So asked "wouldn't flaps 2 work better?" to which he said "burns more fuel". So I asked "....wouldn't staying clean another like, 45 seconds be a lot easier? I mean your green dot is not too much more than 210 I really doubt they care?"

He slowed normally and wound up going with Flaps 2.

Wasn't trying to be a jerk or anything, just never heard anyone ask for that and truly did not get why he wanted to do that at that particular moment. Didn't realize it was "a thing"!

Chris Scott
22nd Nov 2016, 20:49
Hi PENKO,

Maybe your sectors are longer or your cabin crew more efficient? ;)

FWIW, I would never advocate holding with 1+F, and even Flaps 1 (slats only) is hardly ever necessary. ATC rarely refuses a request for a slightly higher holding speed.

BTW, I now realise that the +8 deck-angle I mentioned in my post was rubbish at clean holding speed - sorry. IIRC, +8 is about right for Flaps 1 at "S" speed. At clean holding speed it's around 5 degrees.

Orange future,

Are these guys using 1+F when they should be using Flaps 1, or when they could be clean?

Orange future
23rd Nov 2016, 04:36
Using flaps 1+f instead of flaps 1.

Chris Scott
23rd Nov 2016, 10:19
Thanks, Orange future,

If they are trying to avoid the (roughly) +8 pitch using Flaps 1 (slats only) at "S" speed, it seems to me there are two better options than extending the flaps:
(1) fly faster than "S" speed;
(2) request a slightly higher holding speed than the normal prescribed limit to enable them to stay clean.

I would prefer (2). In my DC-10 days, we often used to ask for a higher holding speed to avoid slat extension, and it was rarely refused. As PENKO says, extending high-lift devices earlier than necessary is not a good idea in icing conditions.