From the July 1997 Issue of Flying Magazine...

The crew of a trawler which sank in the Sea of Japan claimed the ship went down after being struck by a cow which fell out of the clear blue sky and went straight through the hull. No one believed their tale until, a few weeks later, confirmation came from Russia that the crew of one of its military cargo jets had stolen a cow they found wandering on a Siberian airfield and loaded it aboard for the flight home. While the airplane was cruising at 30,000 feet the terrified, unrestrained beast ran amok, so the crew lowered the cargo ramp and it jumped out.