[DaveBirkenstock]

Geeze, I'm at least 3 or 4 posts behind you guys...

I'll try to catch up: The main benefit of this is making a car, airfoil or fuselage more efficient. A typical sedan with a Cd of .34 can be made much more efficient at highway speeds if pressure thrust is used on it's aft end. Fully optimized, the modified car would have a Cd below 0.1, would burn less fuel and would mostly look like it does today.

I'm not sure I'm following the part about the car Cd being higher than the airfoil Cd. An airfoil can enjoy meaningful benefits, too, but because it is much cleaner to start with there is less room for improvement.

The amount of air that needs to be pulled into the car is fairly small & the burden put on the suction system is not too great as to destroy the benefit. There is a synergy at work, where the forward motion of the body, the suction power and the concave geometry prevent drag from forming and create an independent thrust force that all work in concert to make the vehicle more efficient than is possible without this synergy.

The suction system will always lose energy, the thrust force will come with the costs of the strongly adverse pressure gradient on the concave curve, but despite these real & unavoidable losses the whole is still greater than the sum of it's parts.

And because the needed hardware is very well understood and available 'off-the-shelf' the concept can be put directly to work on current production vehicles.

Lastly, the inverse rule of thumb works with all this, too (I think); if the suction pump creates a low pressure area inside the concave part near the aft end, then the outside of that shape will have high pressure (thrust). Right?

Please let me know if I missed a question or important point... or if I'm so tired I'm not making sense any more.

Thanks for your time and consideration... I'm going to bed