Page 10 - Theory and Design of Air Cushion Craft

Contents ix

8.2 Transverse motions of SES in beam seas (coupled roll and heave) 279
8.3 Longitudinal SES motions in waves 294
8.4 Longitudinal motions of an ACV in regular waves 308
8.5 Motion of ACV and SES in short-crested waves 322
8.6 Plough-in of SES in following waves 324
8.7 Factors affecting the seaworthiness of ACV/SES 328

9. Model experiments and scaling laws 342
9.1 Introduction 342
9.2 Scaling criteria for hovercraft models during static hovering tests 343
9.3 Scaling criteria for tests of hovercraft over water 348
9.4 Summary scaling criteria for hovercraft research, design and tests 352

10. Design methodology and performance estimation 353
10.1 Design methodology 353
10.2 Stability requirements and standards 355
10.3 Requirements for damaged stability 363
10.4 Requirements for seaworthiness 364
10.5 Requirements for habitability 365
10.6 Requirements for manoeuvrability 374
10.7 Obstacle clearance capability 376
11. Determination of principal dimensions of ACV/SES 377
11.1 The design process 377
11.2 Role parameters 378
11.3 Initial weight estimate 379
11.4 First approximation of ACV displacement (all-up weight),
and estimation of weight in various groups 384
11.5 Parameter checks for ACV/SES during design 397
11.6 Determination of hovercraft principal dimensions 399

12. Lift system design 405
12.1 Introduction 405
12.2 Determination of air flow rate, pressure and lift system power 407
12.3 Design of fan air inlet/outlet systems 413
12.4 Lift fan selection and design 420

13. Skirt design 433
13.1 Introduction 433
13.2 Skirt damage patterns 433
13.3 Skirt failure modes 435
13.4 Skirt loading 437
13.5 Contact forces 441
13.6 Selection of skirt material 442
13.7 Selection of skirt joints 447
13.8 Assembly and manufacturing technology for skirts 449
13.9 Skirt configuration design 451