Does trailer shape affect towing?

[dodr33]

Hey guys, we currently have a Rockwood 233s hybrid that has a fairly blunt front end...in everyone's experience did the towing change at all when they went from maybe and older square shaped trailer to something more aerodynamic?


Thanks!

[bikendan]

Of course. But unless it's aerodynamic, like an Airstream, you'll still have quite a bit of air resistance. Even a rounded nose does very little to improve anything.

[pgandw]

The shape of the trailer affects it 4 ways.

1. Space inside the trailer is less efficient with a more rounded shape. Even less with a boat.
2. The rounded shape will have less air resistance.
3. Cross-winds seem to have less impact on the more rounded shapes.
4. Probably the biggest difference - a more aerodynamic shape requires less tongue weight to prevent sway.

Compare a square-shaped travel trailer to a monohull boat on a trailer without a lot of superstructure. The boat can get away with as little as 5% tongue weight instead of 15% without causing sway. You seldom need or want a weight distributing hitch or anti-sway device with a boat. An Airstream is perhaps midway between the boat and a square TT.

Fred W
2019 Flagstaff T21TBHW A-frame
2008 Hyundai Entourage minivan
camping Colorado and adjacent states one weekend at a time
next trip: Black Hills - next week

[MtBiker]

WE tow our 15RB hybrid behind a full size Ram 2500 high roof van. Our trailer has almost the same frontal profile as the van does. This makes a huge difference.
We used to tow the same trailer with or F150 4x4 pickup which just hated going into the wind. Felt like pulling a huge sail.
The slope front on the van and the matching shape towed much better into the wind and we get 15.5mpg towing compared to 10.5 with the pickup.

[TitanMike]

When it comes to aerodynamics, the Sears-Haack body is considered as aerodynamic as it gets.

If your trailer looks like this:



then it should tow like a dream. Even Airstreams have a lot of drag, just less than most trailers that are big boxes with slightly rounded noses. Perhaps a Vibe is the most aerodynamic travel trailer on the market today.

FWIW, note from the Sears-Haack body picture, it's not just the nose that matters but the shape of the tail too. A rounded nose will let the air flow around it more easily but if the tail is squared off it just creates a big vacuum that cancels any gain.

[14apex]

...kinda related perspective: Our Casita was hands-down the easiest towing of several travel trailers we've owned over the years -- "slick" & rounded fiberglass, reasonably aerodynamic and light. That said, and as indicated above, the practical & useable space tends to shrink a bit as us campers began to age a bit . We loved and used the "Cassie" for a number of years, but sure do enjoy a much larger camper these days due to having a "big" walk-around bed, a real (non "wet") shower, a slide and lots of really useable space, equipment & storage. "Squarish", lower MPG and 6,000+ lbs. vs. the -3,000 and easy tow of the Casita is well worth it in our old(er) age.

[aceinspp]

Well I thought my V-Lite would do better in helping on wind residence. Nope did not happen. When I towed it with my dulley I saw no great improvement in mileage then I bought a 4 door crew cab 3/4 ton truck. Mileage improved some but not that much. I now tow a 5th wheel more aerodynamic and mpg improved a bit more. 5er weight a bit more thean the V-Lite did. So go figure. Later RJD

[tomkatb]

When testing trailer towing numbers for the SAE spec, they use an aerodynamically good trailer! So I have seen statements from manufacturers reference the area of the nose.

IT all matters. In a TV torque is what matters!

[Dustyhd]

Originally Posted by tomkatb

When testing trailer towing numbers for the SAE spec, they use an aerodynamically good trailer! So I have seen statements from manufacturers reference the area of the nose.

IT all matters. In a TV torque is what matters!

What they use for testing.

“With the exception of trailers defined by rows A and L above, trailers should all be cargo (‘box’) type with flat, vertical front wall and corner radii no more than 152.4 mm (6 in).“