12/24/2013 10:12 AM
I think the life expectancy depends on the intensity of the demands of the ownership. I've seen operations where the expectation was that the equipment inventory had to look and run like new equipment. I've seen operations where the key phrase was that "perception is reality" - out of sight, out of mind. They are making equipment better than they used to. Rust and paint are not as much of an issue as they used to be. Lubricants, fasteners, rubber parts and various wear parts have all seemed to improve. I believe the youngest SST was 20 years old when they flew it to the junk yard.