Aircraft inner tubes were traditionally manufactured from a natural rubber
compound.
A tire inner tube is made by taking a length of extruded "rubber" tube which
is then joined into its circular form by joining it's ends together. This
joining process is generally referred to as splicing.
Natural rubber readily bonds to itself and therefore produced the strongest
"splice".
However, as one writer correctly informed, natural rubber is somewhat porous
and results in a slow loss of air.
In the 1970's a new oil based polymer know as butyl was introduced to the
tire industry.
Butyl is non-porous and solved the problem of air loss but was very
difficult to splice into inner tubes so was only adopted for road vehicle
tubes for many years. Aircraft tubes continued to be made from natural
rubber until relatively recently.
Goodyear were an early user of butyl for inner tubes using the trade name
"Air Seal"
Therefore you have a choice, natural rubber tubes may be less prone to
failure but continually lose air or butyl tubes which may fail earlier but
you will not need airing up very often.
Me ........ I use butyl ....... Why ............ Because I designed the
machines which are now used to splice butyl inner tubes.

Roy - N5804F



"J. Severyn" wrote in message
...
Jay,
I fill mine every few months and they lose 5-8 psi over the 2 months,
which is not too bad.

Check the valve every time after you inflate. I mean check it with a daub
of saliva or a spray bottle of water (soapy water even better yet). I'll
bet the valve is not closing completely. I have had many brand new
aircraft tubes with valves that seat intermittently. Many times I just
flick the center pin of the core after finding it leaking.....and the
bubbling stops.
John Severyn
@KLVK

"Jay Honeck" wrote in message
newsZ5Pe.62789$084.53119@attbi_s22...
One of our least favorite jobs (thanks to our "Fancy Pants" with their
stupid, under-sized access doors) is airing up the tires on our
Pathfinder.
snip

How often do you guys have to fill your tires?
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"