The Visitor wrote:
No oxygen in the nitrogen, (or moisture). Under great pressues the
partial pressure of oxygen makes it highly reactive to rubber seals.
High pressure tires are also filles with nitrogen. However in light
aircraft I have found at least on shop using air in oleos. The say
nitrogen is too expensive as the struts are so leaky. ???

xerxes wrote:

Probably a silly question, but what are the pros and cons of air Vs
Nitrogen filling of the oleo struts. Just how much of a problem would
be the humidity be if they are filled with air. Given the
environmental temperatures would probably never get below freezing
Its for a Cherokee 235. Also pressure Mains at 500psi and nose
300psi.. are these figures reasonably accurate.

Thanks in advance



If the struts are leaking, then they probably need a rebuild. make sure
the shop rebuilding them uses the correct seals (Cherokees use a
quad-ring, not an O-ring. However there are many shops that use an O
ring). Also, make sure the struts are not pitted, as that will tear the
seals in short order. It took me several iterations of rebuilds, but I
finally have struts that don't leak. Also, air will leak faster than
nitrogen if you do have a small leak, plus it will break down the seals.