View Full Version : aerodynamic lift/drag ratio


PetterM
03-28-2008, 09:40 AM
What is a typical aerodynamic lift/drag ratio for high-speed power mono hulls? I am tying to evaluate some results that do not quite make sense.

Mild Bill
04-15-2008, 06:22 PM
Conventional aerodynamic theory plus test results on lifting bodies (http://www.nasa.gov/centers/dryden/news/FactSheets/FS-011-DFRC.html) would suggest that the best aerodynamic L/D of a high-speed power mono hull could not be higher than 3 or 4, and is probably a lot lower.

It depends in large part on CDo, the coefficient of profile drag (the drag due to air flow over the body at zero lift). I don't see how even the most refined high-speed power mono hull could have a CDo equal to or lower than the CDo of a lifting body. If the mono hull CDo is actually much higher (which I suspect is true), any benefit that might be gained from ground effect would be pretty much nullified.

What are the results that do not quite make sense?

View Full Version : aerodynamic lift/drag ratio