Changing inner tubes
 

I recently found an inner tube from 1974 in a permit aircraft that I bought, which was flying up until 2012:

https://farm6.staticflickr.com/5682/...nner_tube_1974

I have to admit the inner tube seems to be in reasonable condition. But do you typically change them more frequently than this? If so, then how do you decide when to change them?

(I do have an inspector whom I trust, and the inner tube has already been renewed. I'm just curious to see whether there's any spectrum of opinion on the matter).

Was it fitted to the aircraft?

According to the file below, it says that tubes should not be refitted. If the tyre was replaced, then I imagine fitting a new tyre would require the fitting of a new tube.


https://www.google.com.au/url?sa=t&r...z6AwuA&cad=rja

I see Dunlop recommend that if the inner tube is stored before fitment, it should be inspected yearly. Also, if it wasn't stored in the manufacturers box, it should be powdered.

I don't know if you can compare aircraft tyres with car tyres, but considering regular car steel belt radial tyres should be changed every 5~6 years (irrespective of tread wear, I might think twice about fitting something this old.

Yes, it was fitted to the aircraft. The other inner tube was from 2006, but I'm not sure when the tyre was changed. I'll see if there are any dates on them.

AFAIK, that recommendation for car tires is due to potential progressive UV damage (sidewall checking) to the tire due to prolonged exposure to the sun. If the car is kept in a garage, and the tires otherwise well cared for (e.g., the car is used occasionally), they will last a LONG time.

The tube is not exposed to the sun, so unless it is otherwise damaged, it may well be in good, serviceable condition. OTOH, the tube, tire, and airplane mfgrs' recommendations should be followed where applicable.