Only one winglet still flying?

From a handling perspective I guess it may just be perceivable in a 744 but you would never notice it in an A330/340 due to the flight control logic. Friends who have flown 747’s with a 5th pod have told ne they could feel that but it wasn’t as noticeable as you would think. Therefore I would assume a 744 with a winglet missing would be fairly minimal in effect.

As far as I understand it…

This situation is only likely to occur after some form of ground handling incident and the the aircraft is required for operations until a replacement or repairs can be carried out. There is little perceivable asymetric handling effect (none in a FBW Airbus) of having one missing however there is a small performance reduction. The manufacturers have to provide an extensive set of performance data with certain items of equipment missing so, bearing in mind you would have to be incredibly unlucky (stupid?) to dink two wingtips at the same time and removing a serviceable winglet doesn’t really help you, there is no real point in doing the approval for this situation.

Thanks for the explanation Wys. Another question… even if flying with one winglet does it create an imbalance in wind drag at all? Or is it just ignorable?

I bet the airlines can only buy a set of two, instead of just buying one :p

😀

I too guess the only reason for not being allowed to fly with both winglets missing is that airframers want to sell winglets.

I bet the airlines can only buy a set of two, instead of just buying one :p

The 747 winglets are held on by three big bolts a couple of bonding leads and a few access panels. To remove/refit one is not a big job it’s just a big awkward lump to “manhandle” on and off. It’s OK in a warm hangar,with an overhead crane and proper access staging (where I did one once!) but outside, in a breeze, off a manlift its another story!! I suspect that is another reason why they don’t remove the matching one.
As wysiwyg says both aircraft’s MEL’s say that one may be missing but not both. They have a short differal time, ten days too. When I refitted one the talk then was more about wing fatigue than fuel burn. I also think that if you dinged the second one “down the line” I am sure you would get a one off differal to get you home.

Rgds Cking

Kabir… I know the 743 doesn’t have winglets, but I was so surprised the 744/A330/A340 can’t fly with both winglets missing I really had no idea whatsoever what the reason might be, so I was just thinking of random reasons, however little sense they made!

Thanks for your explanation, Wysiwyg. Interesting stuff.

Paul

As far as I understand it…

This situation is only likely to occur after some form of ground handling incident and the the aircraft is required for operations until a replacement or repairs can be carried out. There is little perceivable asymetric handling effect (none in a FBW Airbus) of having one missing however there is a small performance reduction. The manufacturers have to provide an extensive set of performance data with certain items of equipment missing so, bearing in mind you would have to be incredibly unlucky (stupid?) to dink two wingtips at the same time and removing a serviceable winglet doesn’t really help you, there is no real point in doing the approval for this situation.

I’d never have imagined that to be the case! Is that for a specific technical reason or does it simply make the aircraft too uneconomical to fly?

Paul

thats an interesting note wys… i doubt its because it turns the aircraft uneconomical Paul, the 743 is around the same specs to that of a 747, so i doubt any economics would invoved. I would think vortices would play a major role in a 744/a340 not bing able to take off without both winglets, although i am stumped how one winglet can be effective without its partner on the other wing, as only one winglet would work, by re-orienting the winglet lift vector forward, thus cancelling parts of the drag.

The other possibility can be in the wing design, as if one winglet is there it can shed its work load by running the plane on specific speeds?

744 and 330/340 can fly with one missing but not both.

I’d never have imagined that to be the case! Is that for a specific technical reason or does it simply make the aircraft too uneconomical to fly?

Paul

744 and 330/340 can fly with one missing but not both.

It obviously doesn’t make the wing asymmetric at all

Have to remember that winglets are only there for fuel preservation, so in-flight i doubt if one is missing it will create any drag problems.

Someone at Air China really needs to attend “Speed Taping 101”!

One of BMIs A330s cliped a lampost at MAN the other week i belive and lost a winglet still flying.

is it just me or are there A330s cursed one of them allways seems to broke. Much the same can be said for Aer lingus i hear there having allot of trouble with there A330s at the moment theres been a world MD-11 covering for one thats been stuck in boston for a week.