I was using a 20 year old T-style bike pump to top off my car tires earlier this evening. I had been noticing the one way valve inside was getting flaky; often when I would pump I would feel the backpressure not just on the downstrokes as normal, but also on the upstroke as well.
As I was undoing the valve connection, I heard a loud noise. I turned around and the T handle had shot off the pump and hit the second story of the house 15 feet away with a loud whoosing and cracking noise. This is an old heavy duty model, and the wooden T handle weighs about a pound, so the launch momentum must have been incredible. It reminded me of the time I accidentally launched a stick of wood across the yard and into the ground when I was learning to use my router table; the launch and impact noises seemed instantaneous. No question this pump could have taken my eye out if I was in its path, and what's scary is that most of the time I was pumping with it my face was right in the firing line.
The pump is now in my garbage can, and I'm ordering the electric inflator I had my eye on:
Amazon.com: Black & Decker ASI300 Air Station Inflator: Home Improvement