The Indian Airlines HS-748 took off from Bangalore to operate Flight IC557 to Mangalore, India. After the aircraft became airborne, Mangalore weather was passed to the aircraft indicating deterioration in weather with conditions below minima. The aircraft arrived near Mangalore uneventfully and ATC informed that it was raining and the visibility was 1000 metres. Therefore, the commander decided to hold the aircraft. A few minutes later, ATC informed that the visibility had improved to 2000 m and clouds were 4/8 at 700 ft. Thereafter, the aircraft was instructed to descend to 3550 ft. Having sighted the runway, the captain turned right to position the aircraft for a left-hand down wind leg of the runway. However, ATC cautioned that the south of the runway was full of low cloud. Therefore, the aircraft took a left-hand circuit for landing. The aircraft landed almost on the middle of the runway at high speed, under adverse weather conditions. The aircraft could not be stopped within the available field length. Its nose wheel was sheared off and the aircraft continued skidding forward and nosed over into a valley beyond the airport plateau and came to stop against two huge boulders on the steep rocky terrain. The aircraft was substantially damaged. Five passengers and two cabin crew received minor injuries. There was a fire under the left-hand engine/wing which was extinguished. PROBABLE CAUSE: “The pilot persisted in landing under deteriorating weather conditions resulting in unsteady approach and late touchdown at a high speed. The contributory factors were non-extension of flaps to ‘land’ position, resulting in increasing landing roll, and the choice of landing on down-sloping runway with a tail-component.”