I'm trying to get a feel for the real life behavior of hover craft air cushions and the associated power consumption. To get a feel for relevant numbers, I'd like to know

  • actual pressure used to lift said hover craft
  • the clearance (average or range) between skirt and water/ground surface
  • the air loss through that clearance

One could treat the clearance as a simple slit, however the air flow under a hover craft is more complex that that due to the round shape of the skirt. In practical operation the craft will hover around an equlibirium where the pressure is "weight of hovercraft" / "area under skirt" and the clearance is higher or lower depending on airflow (or the airflow is higher or lower depending on clearance required). An empirical formula for the relationship between pressure, clearance, skirt length and air flow would be even better, but real life numbers for one situation are ok.

  • $\begingroup$ Have you checked out the ones that were in service from Dover? $\endgroup$
    – Solar Mike
    Apr 26, 2022 at 10:54
  • $\begingroup$ @SolarMike I've mostly hunted around wikipedia, but didnt find datasheets or the links to datasheets there $\endgroup$
    – mart
    Apr 26, 2022 at 13:16
  • $\begingroup$ See en.wikipedia.org/wiki/SR.N4 $\endgroup$
    – Solar Mike
    Apr 26, 2022 at 13:18
  • $\begingroup$ Google search term: "hovercraft design"... $\endgroup$
    – Solar Mike
    Apr 26, 2022 at 13:19
  • $\begingroup$ From the SR.N4 page I can find the the pressure must be near a range ob 1.8 - 2.4 kPa, depending on build, no info on air flow or clearance. But you are right that searching off wikipedia is a good idea. $\endgroup$
    – mart
    Apr 26, 2022 at 13:23

1 Answer 1


Although I cannot assist you with explicit formulas myself, I would like to make you aware of the book Theory and Design of Air Cushion Craft by Liang Yun, Alan Bliault, which is available (with limitations) on Google Books. In particular, I would suggest the chapters; [2] Air cushion theory and [12] Lift system design.

Sure, some pages are not included in the preview, but considering the overall quality of the book, I find this a small price to pay. Having had a look at it myself, I also believe it will be of great assistance, whatever expertise you currently possess in the field of air cushion vehicles.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.