Slamming impact accelerations analysis on small high speed passenger crafts

Abstract

Small high speed passenger crafts (HSC) are commonly known for their poor seakeeping qualities. These crafts are frequently exposed to large slamming impacts and these repetitive shocks may pose danger to passengers’ safety and health. In Malaysia, small high speed passenger crafts having lengths between 7 to 9 meters are mainly used to transport tourists between popular island destinations. Evaluation on impact and vibration for this type of craft was conducted by using accelerometers attached to several locations on craft’s deck. The test was conducted at speeds ranged between 20 to 30 knots and the highest peak accelerations were recorded. The highest acceleration record during the sea trial was recorded at 4.22 g and the average acceleration measure is 2.20 g. Apart from this test, evaluation on effectiveness of the current foam seat typically used in this craft were evaluated using Dynamic Response Index (DRI) and results have shown that the seat is less efficient when impact reaches more than 1g at speeds of more than 20 knots. It is concluded that safety measures such as the use of more efficient suspension seat and limiting the operational speed need to be taken into consideration.