And then the trailer got loose....

My trailer cut loose on my commute home on Monday. I was traveling down a fast hill (was doing between 25 and 30mph when it happened) when I heard a loud bang. I'm not sure what caused it to come loose, but I think the rough roads may have jiggled it loose.

The safety strap did its job and kept the trailer with the bike. Unfortunately, the hitch caught in the spokes which then carried it up and over the hub to wedge between the rear wheel and the seat stay. The wheel initially locked into a skid, but started rolling again after everything bent out of shape. I was able to extricate the hitch from the wheel, loosen the brake, reconnect the hitch, then ride slowly home.

The two pictures show the damage to my bike. Notice that the left seat stay is bent and has a nice dent in it. Also notice that the whole rear wheel is offset to the right. All of the spokes on the left side of the wheel are either stripped or stretched (I haven't pulled apart the wheel to check).

But the trailer didn't get away scot free....

Notice that the hitch arm was bent as well as the seat stay on the bike. The white mark in the upper picture is where the spokes were repeatedly bashing the hitch arm. The break occured where two holes were drilled through the hitch arm. Why were these holes there? I have no idea. But they did make a weak spot that bent/broke in the crash. Perhaps it was a crumple zone by design?