EXPERIMENT ON THE HEAVE OSCILLATION OF A LIGHT AIR CUSHION VEHICLE OVER WATER

Experiments with the air cushion vehicle HEX-5 have shown that over a hard flat ground surface, and over the total weight range of from 5880 N to 12,460 N, this vehicle will not oscillate in heave. A second series of experiments showed that over water the vehicle becomes unstable and oscillates in heave at any lift airflow above 2 m**3/s, over the weight range tested: 7120 N to 10,680 N. The heave frequency is almost constant at 4.6 Hz, over the range of airflow and weight tested. However, it is believed that the frequency increases with decreased weight to some extent at the low airflows, converging to the constant value of 4.6 Hz at airflows of 3 m**3/s and above. The amount of data available is not sufficient to make this suggestion more than tentative. The heave amplitude and acceleration increase approximately linearly with lift airflow, rising from zero at 1.8 m**3/s flow to 0.011 m amplitude and 0.3 g acceleration at about 4.2 m**3/s airflow. The values of heave oscillation experienced on the craft are compared with a generally accepted scale of motion tolerance, and it is shown that the heave can reach quite intolerable values.

• Corporate Authors:

  Canadian Aeronautics and Space Institute

  77 Metcalfe Street
  Ottawa 4, ONo,   Canada 
• Authors:
  • Fowler, H S
• Publication Date: 1980-4

Media Info

• Pagination: p. 92-96
• Serial:
  • Canadian Aeronautics and Space Journal
  • Volume: 26
  • Issue Number: 2

Subject/Index Terms

• TRT Terms: Air cushion vehicles; Amplitude (Physics); Ship motion; Testing
• Uncontrolled Terms: Heaving
• Old TRIS Terms: Air cushion dynamics; Air cushion vehicle performance; Heave amplitude
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00331706
• Record Type: Publication
• Source Agency: Engineering Index
• Files: TRIS
• Created Date: May 21 1981 12:00AM