Anecdotal, but... I was on a flight from Chicago to Raleigh a few years ago, and we were just starting to taxi out to the runway when the plane stopped and the

Anecdotal, but... I was on a flight from Chicago to Raleigh a few years ago, and we were just starting to taxi out to the runway when the plane stopped and the pilot got on the PA and said something like "Sorry folks, we have a maintenance indicator (kind of like a 'check engine' light) that has come on. We have to go back to the terminal and get maintenance to check things out." So we go back to the terminal, wait approximately 3 times longer than the expected lifetime of the universe (OK, that part might be an embellishment, but it felt like it at the time. The rest of this story is true though). Anyway, after a bit the pilot comes back on the PA and says something approximately like: "OK folks, a $FRIZGIBBIT on this plane is broken. Thankfully these planes have two $FRIZGIBBITs and are certified to fly with just one working, so we're going to go ahead and get underway and get you all to Raleigh." And that's just what they did. Frankly I was a bit nervous about the whole thing. I don't know what the hell a $FRIZGIBBIT is or what it does, and they say it's OK to fly with just one, but the way I figure it, somebody decided to put two in the first place for a reason. What if the remaining one breaks mid-flight?? Anyway, it all worked out in the end, or I wouldn't be here to tell this story, but the point is, planes do apparently fly on occasion with broken something-or-others.