I just wonder...

[janzman]

...Its just a thought but we all know how car manufacturers try to make their cars as light as possible in order to be more fuel efficient,get more mpg and generally be more beneficial to the environment.Now given that a 5lt tin of domestic 'dulux' emulsion weighs about 6kg I wonder how much paint is needed to respray a commercial airliner such as a Boeing 747-400 and, more pertinent, how much does that paint weigh.I recall American Airlines didnt paint their fleet ,just a clear laquer over the bare metal,how much more fuel efficient would that be....like I said just a random thought for an otherwise lazy Sunday afternoon.

[Skids]

Aircraft paint is usually lightweight acrylic based and sprayed on in the thinnest layer possible and doesn't require laquer.
However, aircraft paint jobs do get touched-up as it is erroded away or removed by some other means. It is important with aircraft to maintain their centre of gravity and to this end they are weighed when they are brand new and are continually weighed through their lives. It is not unknown for aircraft to be overweight simply due to the amount of touch-up paint applied over the years.

[janzman]

Im not suggesting aircraft are overweight ,I just wonder, if they were lighter would they be more fuel efficient.By Googling 'commercial aircraft painting' a whole list of specialist companies is displayed.When a plane is sold from from airline to another it needs a full respray and livery.Airlines operating in the middle east for example need respraying on a regular basis due to the abrasive properties of sand.
I do appreciate aircraft paint is in no way similar to dulux,my analogy was for illustration purposes only. :-)

[wildwood]

It may be that the thousands of rivets and joints on one plane are smoothed out with paint and so reduced drag, offsetting to weight of paint.

There are however ways to reduce pollution as outline here...

http://www.reliablepl...aft-painting-process-

[dundurn]

I seem to remember this very topic being covered in New Scientist many moons ago. BEA had adopted a livery where the underside of each aircraft was painted red. Someone worked out what this weighed and the opportunity cost in potential freight traffic and conversely the extra fuel cost. I believe a fully painted 747 is carrying between 1000 and 1200 lbs of paint.
On the other hand - unpainted aircraft need to have anti-corrosive treatments and paainted aircraft are giant advertisements - you pays your money and you takes your choice - beancounters somewhere will have worked out the cost benefit swings and roundabouts.

[rov1200]

A planes weight is very important in design which is why the new Boeing Dreamliner is gaining world acclaim. The fuselage is made of composites. However some believe there could be future problems because a lightning strike would not disipate along the fuselage as in metal structures. It has passed the certificate of air worthiness so the problem is well known about.

The theory of lightning hitting an object has been well demonstated with the "Maxwell's cage" experiment readily available on internet lookups.

[jomifl]

Faraday's cage surely?