Effect of a responsive skirt on air cushion vehicle seakeeping

The skirt system, which will be excited to make a response motion under the outer disturbance, is treated as a passive control system, and the longitudinal motion equations of ACV are derived according to the control principle. The influence of the skirt response in waves on ACVs seaworthiness is analyzed in the paper. Some results are gotten that the greater vertical deflexion of skirt will make the response of heave, pitch motion and acceleration of the craft decreased a lot, but the horizontal deflexion will go the opposite way. The natural frequency of skirt plays an important role in seaworthiness improvement, the adoption of lower frequency skirt can make the frequency band of craft motion response narrower effectively. The matching of skirt parameters of bow and stern has a certain effect too.