FairWeatherFlyer,
One of my pet gripes is that the auto industry treats aerodynamics as a styling inconvenience. Would i chose an otherwise similar car with 1/2 the Cd - yes. I suspect most others are the same. Apart from some pretty poor attempts at city cars no one has really made any effort to produce a tandem seating car with aerodynamics optimised for high speed commuting.
Lets do a simple calc: A K21 glider seats 2 in comfort, and will glide at 50KIAS (25.7m/s) at 34:1 lift:drag. It weighs 365kg, so lets allow 2 pilots and lots of "baggage", to bring the all up weight to 565kg. This means it requires a "power" of
25.7m/s x 565kg x 9.806m/s^2 / 34 = 4.188 kW or 5.61 BHP
My little diesel VW tops out it's little 64SHP (47.7kW) engine at Vh (
) cruising of 100mph. So at Vy (
) of 50KTS or 57.5mph requires
64HP x (57.5mph / 100mph)^3 = 12.2 BHP
It requires ~2 times the power to do the same job! It does not suffer induced drag from any wings, which any aerodynamicist will tell you well outweigh the fuselage drag. Basically the stylist did most of the aerodynamic calculations with a blunt crayon!
You can see why i get annoyed when the guage reads bingo...
Edit to say:
Thanks for the correction, D3 - one of my "Doh!" moments.
Fortunately the calc still shows my point.
If every car had half the Cd, which is a realistic target, then you could have a serious impact on the CO2 produced by the transport sector.