aerodynamics

Traded an 10000 lb. plus fifth wheel for a Jayco WhiteHawk that weighs about half as much. Took the WhiteHawk on an extended trip for the first time last month (320 mile trip to Fl. Panhandle mostly on Interstates). I was shocked the fuel mileage I was getting (3500 Ram diesel) was no better/slightly worse than towing the fifth wheel. Apparently the airflow over the truck cab, through the bed, and into the sloped nose of the TT produces quite a bit more drag. Fuel mileage to the Panhandle 10.6 mpg, trip home 11.6 mpg (driving on cruise @ 60mph except for about 60 miles driving on secondary roads both legs of the trip). So yes, a towable RV possesses the aero properties of a brick.

The aerodynamics of a trailer really does make a difference. I can't quote actual numbers here like others will since I don't know if you save 2 or 3 mpg or not. But I can tell you of my experience. I used to pull a 21 foot hybrid with my current truck. I changed to a 25 (actually 26) foot Airstream. Using the same truck, going the same places, packing the same equipment and traveling the same speed I found that my mileage did not change. Even though our current trailer is 5 ft longer and 2000 pounds heavier, we get the same mileage. The only other variable here was the shape of the trailer.

Some people question what a few hundred extra pounds will do to their mileage. The extra weight of the water or equipment is a minor issue when compared to the size and design of the frontal area of your trailer.

ROBERTSUNRUS wrote:

beemerphile1 wrote:
A little better than towing a barn behind you. :B Good aerodynamics and RVs don't really fit well in the same sentence.

:) Hi, some do!

:R

Yeah...popups!

beemerphile1 wrote:
A little better than towing a barn behind you. :B Good aerodynamics and RVs don't really fit well in the same sentence.

:) Hi, some do!

A little better than towing a barn behind you. :B Good aerodynamics and RVs don't really fit well in the same sentence.

Whatever TT you are towing, you are towing an 8 foot by 8 foot wall.

Is that model especially good or bad? I agree with @westend: Bog Standard. They all have all the aerodynamic advantages of a cinder block.

Bog standard.

Won't make much difference. Maybe 1 mpg. There isn't a trailer made that will have 3-4 mpg advantage. A large part of the problem is drag from the back end of the trailer...

B.O.

Compared to what?

Frontal area is frontal area- the smaller, the better. This trailer is aerodynamically "better" than something wider/taller, and "worse" than something narrower/shorter.

Trailers with similar areas but rounded corners may have slight aerodynamic gain, but as a practical matter such gains are only realized after many thousands of miles.

It’s a big brick being dragged behind you… good, fair or poor, you forgot no aerodynamics, that is needed to describe it’s aero efficiency…