See other failures under 000.html.
Broken crank. Cause of failure unknown. From http://upload.wikimedia.org/wikipedia/commons/9/96/Pedalarm_Bruch.jpg as of 2008/08.
Make/model and service history are unknown.
This is a close-up of a failure pattern typical of a crank where arm and spider connect with a sharp edge. Dark areas failed well before full failure; the "beach front" nearly-parallel lines show the direction of progressive failure with continued use; the silver part failed last and failed quickly.
Note also the inset picture shows severe eroding of the contact with the pedal axle.
The picture appears as part of the article http://en.wikipedia.org/wiki/Fatigue_(material).
See also FAIL-090.html.
