I've read stuff here and elsewhere about a cane being an ideal defensive weapon for an airplane flight, since it is both an effective weapon and something you are allowed to take through airport security. However, I've never gotten one because I thought it would be difficult to justify carrying it. I'm not realy old enough, nor do I have a limp or any knee surgery scars to point to if the TSA folks ask me, "Do you need that to walk?"
Earlier this week, while I was waiting to board a flight (to California, unfortunately), it came to me. The perfect excuse to carry a cane, one which doesn't require faking a limp or dying my hair (more) gray. If anyone asks why I need it, just say, "When I sit for a long time, my knee stiffens up."
For me, at least, this has the added benfit of being true. My right knee does tend to get stiff if I sit for a long time, like a long airplane flight, though it's not enough to really need a cane. However, even if it's not true at all, it's the perfect excuse. Because the knee doesn't stiffen up until the end of the flight, it explains away the fact that I don't look like I need the cane when I go through airport security. On the other end of the flight, nobody is going to check to see if I need the cane when I'm leaving the secure area of the airport (they're only concerned about people going the other way).
Of course, the cane also has advantages when I have to visit someplace like California, Chicago, or Washington D.C. that requires me to leave my sidearm at home.
Now I just need to get a good, solid cane and some training in how to use it before my next flight.