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20Legend
8th Feb 2008, 09:37
Was looking at this pic (http://www.airliners.net/photo/Japan-Airlines--/Boeing-747-446F-SCD/1325293/M/ </photo/Japan-Airlines--/Boeing-747-446F-SCD/1325293/M/>)

Its a cargo aircraft so no doubt flying full laden a lot of the time. Has the paint been stripped to save on weight and fuel costs? If so what typical saving per flight are likely to be achieved?

WHBM
8th Feb 2008, 09:56
American Airlines have never painted their aircraft since metal fuselages came along in the 1930s, apart from the A300 which requires a special coating. It does save weight, cost, and the downtime when repainting, there seems to be a bit of extra maintenance in return. A few others (as here) do the same. It seems to be sufficiently minor that it's down to the corporate identity whether to go for it or not.

FCS Explorer
8th Feb 2008, 10:20
it takes (roughly) 100kg to paint a 737
and
roughly 10kg fuel to carry an extra 100kg weight on a 4 hour flight
or maybe 2,5kg each hour for the paint.
these numbers/calculation will not stand a proper scientific crosscheck, but i think they give some idea....

20Legend
8th Feb 2008, 11:02
This one (http://www.airliners.net/photo/Cathay-Pacific-Airways/Boeing-747-444(BCF)/1323568/M/) is a BCF, so I presume CX stripped the paint from the previous user and just didn't bother painting fully

GOLF_BRAVO_ZULU
8th Feb 2008, 11:09
Is that the weight of solids remaining after application or the weight of paint with solvents and carrier?

perkin
8th Feb 2008, 11:58
Solids remaining after. I understand all aircraft are accurately weighed both before and after a paint job...

spannersatcx
8th Feb 2008, 12:06
This one is a BCF, so I presume CX stripped the paint from the previous user and just didn't bother painting fully

It is a CX pax converted a/c. Although not a lot is saved per flt in the short term a study was conducted and the savings over a 5 year period were quite significant. runs into $00,000's.

Spanner Turner
8th Feb 2008, 14:12
Is that the weight of solids remaining after application or the weight of paint with solvents and carrier?


Aircraft (large Boeings anyway) are painted with polyurethane paint, in effect they are coated in plastic which on a 747 adds up to 'quite a bit' - a few hundred kilo's. Its a two part mixture and cures via chemical reaction between parts A and B. Not via the evaporation of solvents so only a minute amount of weight is 'lost' from the paint mixture during the curing process (Judging by the awful smell in the hangar during painting at least a little of the mix ends up in the atmosphere/lungs)

:ok:

20Legend
8th Feb 2008, 16:53
so maybe saves them a bit then, but more of a corp thing by the sounds of it

PierceAviation
9th Feb 2008, 04:41
American Airlines have never painted their aircraft since metal fuselages came along in the 1930s, apart from the A300 which requires a special coating. It does save weight, cost, and the downtime when repainting, there seems to be a bit of extra maintenance in return. A few others (as here) do the same. It seems to be sufficiently minor that it's down to the corporate identity whether to go for it or not.

AA uses a special polish that is made for them from a shop in Georgia. I had to cal this shop to find out what I could use to strip the polish off when I was the project manager on a couple DC-9's they sold. The shop would not tell me the chemical make up but did tell me what would cut the polish. So the man-hours spent keeping the aircraft polished does hurt on the return of investment of not carrying the extra weight.

Solids remaining after. I understand all aircraft are accurately weighed both before and after a paint job...

Not always...there are mathematical methods that can be utilized to determine the new weight. Depending on the paint scheme, the old paint thickness is measured...usually 4 to 8ml thick. Then the new paint thickness is measured and mathematically the weight is found and the difference is add to, or subtracted to the Basic Weight of the aircraft.

Regards,
Greg