Thanks. I assmued that the lifespan was pretty long no matter what you did
to them. Since I use the out tanks so infrequently, I will probably coat
them with some preservative.

Mike
MU-2

"Newps" wrote in message
...
I had bladders on my 182 and now have them on my Bonanza. Obviously the
best is to leave them full. I never had full tanks unless I was going a
long way, just wasn't going to put up with the decrease in performance
lugging around all that weight. What really hurts the bladders is to be
left outside in the baking sun, second is the temp change associated with
being outside. If there is any condensation as night falls now you have
water on the top of the bladder. This doesn't help bladder life. The next
best thing to keeping them full is an insulated hangar so there's no sun
damage and the change in temp is slow. New bladders now a days last about
30 years, not keeping them full using the above methods will reduce that to
25, so go for it. I didn't coat the bladders with anything.



Mike Rapoport wrote:

I have a Helio Courier with four fuel cells holding 30 gallons each. My
typical flight uses ~35 gallons so I would like to leave the outer (aux)
tanks empty most of the time. I understand that leaving them empty will
reduce their life expectancy. How much should I expect the life
expectancy to be reduced? It there a proceedure to coat the inside of
the bladders with something that would preserve them? Thanks!

Mike
MU-2