Disasters and Recovery

Repairing a 50-year old mechanical computing device can be difficult. Why would you expect that repairing a 100-year-old electromechanical device would be easy? Do you expect the universities to start turning out thousands of Wesley Crusher clones or something? Perhaps you're assuming that hard drive technology will be so advanced by 2099 that any twelve year old will be able to figure out that old 1999 stuff. But that's not a very reasonable assumption. Just because the technology gets more advanced doesn't mean that the older stuff becomes any simpler. If we're still using disk drives in 2099, they might bear so little resemblance to the ones we have now that few people will even remember the details of how the 1999 drives worked. (After all, few people *now* know the precise details of how the 1999 drives work.) You look at a disk drive and say, "Oh, that's simple, a disk spins and an actuator moves a magnetic head back and forth." But if it is so simple, why didn't they have 18G 3.5 inch drives 25 years ago? Just like any complex technology, there is an awful lot of detail that goes into making it work. And a lot of that detail isn't written down on paper *anywhere*. It's in the heads of the engineers. If we wanted to build Saturn V launch vehicles again, for instance, a lot of things would have to be relearned. Just because we have the engineering drawings does NOT mean that we fully understand it or know what it takes to make it work reliably.