I think that the quality of the paint wasn't that good. Every aircraft needs to have a torough check every X years (I think 5 years), then they come back repainted.
It is just an upper layer and isn't dangerous but it sure isn't nice. This reminds me of all the Air France dirty aircraft:
It is very strange that only on the aircrafts top the paint is gone. And not around the cockpit were is more friction of the air? Or use they other paint on the top than on the rest?
I saw this very plane two days ago: the situation has become even worse. I thought that the plane was white on top of the fuselage.
Do they really have to wait a D check to re-paint it? Can't it be done at a C check (last C check was April 2003, long after the picture in the first message of this thread was made).
I think it's because of the sun and ot enough paint.
When a Airplane is flying at for example FL340, the are not much clouds there right? So he has full sun.
Do they really have to wait a D check to re-paint it? Can't it be done at a C check (last C check was April 2003, long after the picture in the first message of this thread was made).
No they don't need to do that on a D-check, but they don't wanna waste too much money
Perhaps it's just a cheap paint and the color pigments are not mineral but organic and decompose in the harsh conditions of FL340. So the paint still protects the aircraft, but does not retain its color. This would explain them not putting a new red layer 8O
During my job, I asked the same question to some employees of BGS (because they do the handling of VEX).
Some of them told me that the red disappeared after using a wrong product with de-icing. I don't know what to believe, is it possible?
Glider,
As a chemist I can tell you that it is quite possible. The deicing products are also strong solvents. But serious paint manufacturers know that and they have special aircraft paints that can resist to those solvents.
If you want to see tatty, shabby looking aircraft, then look no further than the Fokker jet fleet of KLM. I've never seen one of those which looked remotely clean (puts Air France in the shade!) The tail fins on those aircraft are literally black sometimes.
Sabena and Sobelair - gone but never forgotten.
Louise
Low cost paint 
