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ShedsRus
26th Dec 2007, 20:05
Ax an ex light aricraft engineer and semi professional SLF (I work to pay the fares) I would like an experts answer to:
Amsterdam,boxing day, KLM 330 minus R/H winglet - L/H in situ. A/C being readied for commercial flight. The winglet looked as it it had been removed engineeringly rather than side swiped - there being no speed tape around that area.

Questions: What, if any, degradation of performance is there?
If it was off on a flight is just one winglet OK as per the MEL?

I often see A330's, more than other a/c, with bits of speed tape in various places (wing leading edges seems a speciality). This is obviously an offically approved 'keep it flying' temporary/more than temporary repair. What sort of size/time restrictions are on these sticky patches.

Thanks to anyone taking the time to unglue my little grey cells and seasons greeting to all

Hand Solo
26th Dec 2007, 20:15
I don't know about the A330 but on both types I've flown other Airbus and Boeing types with winglets and on each there was something like a 1% fuel burn penalty for a missing winglet. I can't remember if the Airbus could despatch with both winglets missing but is restricted to one absent winglet only. I'm not sure of the exact time limit on the MEL but I reckon it's at least ten days as ours aircraft tended to hang around for a while before the winglet was replaced.

ShedsRus
26th Dec 2007, 20:24
HS - thanks for the rapid reply. If the penalty is that low what benefits do the winglets give to performance, fuel economy etc.

Winglets, on other Airbus models, appear much smaller than the 330 (that may just be my one dicky eye that gives that impression) so by that reasoning(?) the penalty would be greater on a 330 than other models.

Probably talking b*****ks but the grey cells are still porridge.

Still nice to get such a quick response.

Hand Solo
26th Dec 2007, 20:42
A 1% fuel penalty would be significant over the course of a year, especially at todays fuel prices! I suspect one of the reasons the winglets are smaller on the small Airbusses is that the wings tend to be optimised for where the aircraft will spend most of it's time. An A330 will spend a lot of time in the cruise, hence if a winglet can reduce burn in the cruise it's worth a lot. A short range aircraft like an A319 will be up and down all day long with the wing optimised for that regime. I had heard that the winglets were originally added to the 320 series to reduce wing flutter. One must also consider that while the 330 winglets look much bigger then the 320, the 330 also has a much bigger wing so the proportionate effects could be much the same.

Down Three Greens
27th Dec 2007, 09:30
The information you require is normally contained in the Configuration Deviation List of the Flight Manual. The A330's is as follows:-

(m) One may be missing provided hole is covered.
Increase fuel consumption by 1 %.
Reduce the takeoff and approach climb
performance limiting weight by 2.5 %.
Reduce the one engine inoperative ceiling by
250 ft.

There is no time limit on CDl ITEMS but...

GENERAL

The configuration deviation list belongs to chapter 2 LIMITATIONS ol this flight manual. Flight with certain secondary airframe missing parts is possible, as indicated in this kst Any part not included in this list must be considered as necessary.
It is important to repair the airplane at the first airport where repairs or replacements may reasonably be made, since additional malfunctions may require the aircraft to be taken out of service. A Letter (m) against an item indicates that some maintenance action is necessary to permit flight with these parts missing. Refer to he related Section of the Maintenance Manual for this information,

LIMITATiONS
No more then one part or one combination of part of one system may be missing Parts of different systems may be simultaneously missing, unless otherwise specified with this list. When a missing part introduces additional limitation this limitation is indicated in the Remarks and/or exceptions column. This limitation comes in addition to limitations of chapter 2 of Flight Manual. It must be clearly indicated by a placard on the captains instrument panel

PERFORMANCE
Perfomance penalties are cumulative unless specific penalties for particular combinations of missing parts are indicated. These take off, en route and landing penalties apply to the most limiting corresponding weight.

Hope this helps.

DTG

ShedsRus
28th Dec 2007, 16:37
DTG. Many thanks for the reading from the manual. It ticks all my boxes and I thank you and HS for taking the time to give such a detailed response.

Have a good 2008