This is what happens when the weight of the sled exceeeds the load bearing capacity of the ice. You'll have to ask Andrew what went through his mind when he stopped moving forward and started going down.
We were riding near New Ulm on the Minnesota River this past February (2000). As we rounded a bend, there was a large spot of freshly frozen water; we decided not to chance going across it and turned around. It so happened that the spot where Andrew chose to turn was on top of a drainage culvert inlet. The ice was thin and, well...
Thankfully, Sam (the guy to the far right of this picture) had packed along rope and come-alongs. He's had experiecne pulling sleds out of less than solid terrain. We tugged and cranked, but had a tough time pulling the Coug out of the drink. It turned out an edge of the culvert was caught under the rear tunnel of the sled. (That's Nick - wet boots and all - inspecting the skis.)
Boy, does he sure looked RELIEVED!
Finally! It only took 90 minutes to get her out. A few pulls on the rope to clear the crankcase and cylinders of pure MN River mudwater, a new set of spark plugs, and she started right up. I tell you, that Cougar is a TANK! (You'd believe me if you new what that machine has been through.)
If you'll note the hole to the left of the sled, that's where Nick showed everyone how to gracefully fall through the ice! You had to be there!