Four sailors are lucky to be alive today after a terrifying encounter in the remote South Pacific, where a sperm whale cracked the hull of their yacht, ultimately sinking the vessel and forcing a harrowing fight for survival on the high seas. The dramatic incident occurred roughly 250 nautical miles north of Norfolk Island when the massive marine mammal suddenly struck the boat. According to the sailors, the violent impact was completely unexpected and immediately life-threatening. Video showed the boat barely above water: “There was sort of a loud thud. The whole boat was pushed sideways,” recounted crew member Jemma Cooper, who was thrown from the steering wheel. Initially confused by the terrifying crash, she soon spotted the culprits in the water. “We looked out to our port side, and there were six to eight, a pod of whales there,” she explained. Her husband, Jeremy Cooper, was sleeping below deck when the collision jolted him awake.…