After crossing the Mondi intersection inbound for an ILS RWY 5 approach, the captain felt that a proper descent was not possible due to a strong tailwind and their present altitude. They turned and proceeded outbound to lose altitude. The crew then established themselves again on the inbound course at an airspeed of approximately 120K. The copilot reported that around 300 ft "the bottom dropped out." The aircraft crashed onto the surface of a frozen cove and slid onto marshy terrain, stopping about 500 ft short of the runway. An NTSB weather summary shows that the following wind regimes existed when the aircraft made its approach: 5000 to 24000 ft ASL, wind 220/50; 2400 to 450 ft ASL, wind 180/30; 450 ft ASL to surface, wind 100/5. Using the above wind regimes and assuming an approach airspeed of 123K, the following ground speeds were computed: 5000 to 2400 ft ASL, 155K; 2400 to 450 ft ASL, 147K; 450 ft ASL to surface, 118K.