The escapement gears on any typewriter are generally very small, yet very reliable.  Now the escapement mechanisms that surround it aren't so much--but the gear that meshes against the carriage rack almost never has problems.  But if you ship something UPS, no matter how carefully you pack it, there's a possibility that it'll break.

I honestly think they'd have had to drop it from a 3-story window to make this happen, but it happened.  A 1948 Royal KMM was shipped out in perfect condition, and arrived broken.  As shown in the picture, the escapement gear has a little chip in one tooth, and that caused the pinion pawl to flip, and that made the carriage unable to do anything but slide all the way to the right.

Obviously, a part like this has to come from another machine.  Getting it off isn't too terrible, but putting it back on can be kind of a chore.  Especially if you don't have tiny kid's fingers.

Well, it occured to me that I ought to record the method, so in the video below, I show you the easiest way to get the escapement wheel and gear back into place and working again.