Using a hitch as a recovery point is a perfectly acceptable practice as long as it is not one of those cheesy receivers that bolts to a bumper. While not ideal, it’s far safer to use a hitch pin ...

The SR-71 Mach 3 spy plane is built of titanium, with titanium nuts and bolts. The sockets also have to be made from titanium, because the nickel in standard sockets corrodes the titanium bolts.