Flap retraction on landing?
 

Hi all,

Just saw a clip of a B747-400 crew retracting flaps on landing never seen this done before on any type.

This was a full stop landing and not a touch and go. Only thing I can think of is perhaps due to the characteristics of the landing airport i.e some sort of limitation or restriction (Runway length, obstacle or terrain).

Unfortunately I dont know which airport they were landing on.

Anybody got the actual reason for this? Or better still anybody fly into airports were this technique is used by your SOPs, does not have to be 747.

Many Thanks.... prune away...

Aka

Unintentional perhaps?

The only airplane where this was recommended, that I can recall off-hand, was the F.27/FH227, but then, flaps were to be retracted to the 16 degree position, to enable maximum effective wheel braking, for landing on very short runways.

No large jets that I know of...seems strange to me.

"Unintentional perhaps?"

I'd be amazed if it was unintentional, the B747-400 has a restrictive flap lever gate which prevents you accidentally selecting flaps up in one smooth movement. It's at least a two or three stage process and not in the SOPs I use.

Where did you see the clip? Is there a link?

Maybe it could've been a training flight an they were taxying back for a further takeoff and hence retracting the flaps to the TO position.

Regards,
BH.

I know of a couple of incidents where the F/O (flap operator - literally) has fought with the flap/slat lever of a B717 and retracted slats instead of just selecting Flap 0.

Despite the struggle to achieve this, I'd be most surprised if any of the F/O (flap operators) actually meant to do what they did, ergo, unintentional.

Does AKAfresh mean that the flaps were retracted on or very shortly after touchdown, or, during the landing roll?

The -400 automatically retracts the outboard 2/3s of its slats with selection of reverse, maybe that was what you saw.

Ok folks thanks for the input but just to clear some things up....

Definitely not unintentional simply from the way the FO moves his hand.

Also the retraction was to a medium flap setting ie not to ZERO (i dont know the flap settings for the 747... movement of flap lever eg flap 35 to flap 15) and was done upon inital touchdown not the ground roll. I think 411A has got it here!


"Right Way Up" - This was not an automated movement but a physical movement of the lever by the FO's hand. The only thing I can see moving by itself was the spoiler lever upon touchdown, but this is normal.

With regards to "Bullethead's" comment about training flight.... good point but it was a night flight so i doubt it.


Anyone done this in practice as per your SOPs?

Aka

Look, rather than flog this to death, what 'clip' are you talking about? Which airline/country/nationality/operator, because what you are insisting took place would not happen in any normal operation. It would not be a touch and go because the auto-spoilers operated. The only other option is some sort of contaminated runway to prevent flap damage from debris, but for a 747 it seems very unlikely. I have never heard of this, so let's have some details please!

The only aircraft I have ever flown or heard of that it was approved/recommended to retract the flaps immediately after touchdown was the Sabre 40/60/80 series aircraft. This was for better braking efficiency.

This would not be SOP's, unless this particular airline has good reason to deviate from Boeing's recommended technique. Perhaps you can give further details as to where the "clip" originates and which airline is involved?

How about you providing the URL of the clip you saw?

Link
 

ok ppl.... here it is

Having looked at it again looks like flaps were set to ZERO... but ill let the 747 guys comment on that.

http://www.youtube.com/watch?v=oSeqy...eature=related

Aka

He's doing no more than retracting from full flap to next position to full. Why, I don't know, but a full retraction of flap goes far higher than his arm went. Maybe a particular airline SOP for some reason, but they are not fully retracted.

So the link is up what do you think?

Aka

A peculiar SOP. Just about unique, and should be stopped. Maybe someone upstairs thought they should reduce flap vibration during reverse power by retracting one position.

I suspect that it is that particular airline's SOP to configure the aircraft for a baulk landing; not a Boeing procedure. I agree that it should be stopped.

well i have a slow internet connection, but if in that video, leading edge flaps (slats) are retracted, then its normal. Upon engaging thrust reversers, LE Flaps go up. This has to do something with the aerodynamic braking sort of thing. Will ask my dad about it and let you knw the exact reason.

No, this was filmed from the flight deck and it was the actual flap lever that was moved.

No, this feature is to protect the slats and the LE anti-ice equipment from being damaged by FOD which may be "blown up" by the reverse thrust.

Flap retraction on initial touchdown?
 

Has anyone heard of this practice being used when you land with a tailwind?


YouTube - ANA Boeing 747-400 Cockpit view for Landing

No. It appears to be an ANA specific procedure, possibly to "prepare for" a balked/rejected landing as someone else pointed out.

HOWEVER, even that rationale is misguided, because a landing should NOT be rejected after the reversers are deployed. The FO did not retract the flaps (looks like to 20) until after the Captain selected Reverse Thrust.