Shortly before the Soviet Union fell I designed a grinding machine for one of the Soviet automotive companies to grind the ID
of the outer shaft for a Rzeppa joint. We built and shipped two of them; they were never installed in the plant to the best of my knowledge (since part of the contract was sending someone over to supervise the installation and run the machine off in the customer's plant, and we never sent anyone). As far as I know they are sitting in a warehouse somewhere still in their shipping crates. Hopefully these 737's will have a better fate.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler