look at the space shuttle when its on the 747 carrier plane. They cover the engines with a pyramidal/conical thing to reduce aerodynamic drag by changing the shape of the back end. They do the same thing with rifle bullets, it called a "boattail".

With hatchback cars you can see it clearly. With container trucks and SUV's, you see that its NOT there. The back end of a 40 foot container truck and a SUV are relatively flat. For bullets, most handgun bullets have a flat base. I propose sticking something pyramidal or conical on the back of trucks/SUV's. Maybe hollow or made of foam so it doubles as an energy absorber in rear end collisions. For trucks its much easier to do. For SUV's its more difficult. You have to avoid covering the lights, liscence plate, and more importantly the back window by cutting or reshaping it or using transparent materials.
-- vmaldia, Aug 03 2006

(?) Tractor-trailer aerodynamic solutions http://www.roadstar...006/04/030a0604.asp
Lots of info on devices to save fuel on trucking. [wittyhoosier, Aug 05 2006]

(?) Roadrunner Superbird http://e-carzone.co...runnersuperbird.jpg
I remember being about ten years old and seeing one of these coming up the street - I was stunned. [normzone, Aug 05 2006]

The idea makes sense for articulated lorries, but not SUV's...mostly because of the drawbacks mentioned in the description.

I wonder how much the coefficient drag would actually be lowered on, say, a 45 foot container equipped with such an aero device.
-- ed, Aug 03 2006


I could see an aftermarket or small-volume application for this, for, say, companies that need to transport large motor homes across the country to their dealerships or owners. Bun.
-- RayfordSteele, Aug 03 2006


this is a good one, the simplest ideas are more readily accepted by the masses. Bun
-- auricom_mech, Aug 04 2006


THough it would have a benefit, keep in mind that 747s are traveling and 400mph or something and rifle Bullets are even faster. Under those conditions aerodynamic drag can be a really big issue. It is far less of a problem at 65mph.
-- jhomrighaus, Aug 04 2006


This is baked for semi trucks, lots of info in the link. [Brau]- the funny looking Roadrunner Superbird and Charger Daytona were basically outlawed from NASCAR because of their 'unfair' advantage of aerodynamics. I will grant though, that the Daytona wing is of little or no use on either a street vehicle or a truck.
-- wittyhoosier, Aug 05 2006


Well, with an SUV you don't have to worry about covering up the turn signals - they don't use them anyway.
-- normzone, Aug 05 2006



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