Mika,

My 32 year old, 2000 hour (most of that in Finland, a few years in Sweden)
B4 is still in good condition. It spends 7 months outside and the winter in
a non-weatherproof, canvas covered trailer.

The repair manual has a section on corrosion protection detailing the
various methods used during manufacture. It also lists different types of
corrosion, their causes and symptoms as well as how to repair affected
areas.

There are plenty of old Cessnas still flying. I think that looking after the
paint, a good annual inspection and careful pre-flight inspections will pick
up any problems early and keep my glider flying for many years.

More information, manuals and spare parts available from:
http://www.ewms.ch/

Edward.