Trailer sheds weight and cost—not style

DN Staff

August 7, 2000

7 Min Read
Trailer sheds weight and cost—not style

Dayton, Ohio -Picture an Airstream trailer, those sleek aluminum recreational vehicles that have crisscrossed America's roads for nearly 70 years. Look how the sun plays off the curved metal surfaces as it slices down the highway. Now picture its owners. Look how the sun plays off their graying hair as you pass them with barely a tap on the accelerator.

Like other recreational vehicle makers, Airstream now faces a demographic dilemma. Older folks towing large full-time trailers with large vehicles keep the company rolling along. Yet a huge untapped market of younger buyers awaits if only Airstream, a division of Thor Industries, can build smaller trailers that appeal to them. Airstream may have an answer to this quandary in a new line of trailers that are easier to tow, buy, and maintain. "We believe we've come up with something that will appeal to age groups from the Baby Boomers on down," says Rex Miner, Airstream's vice president of product development.

The new models represent an update of the "Bambi" trailers that Airstream introduced more than a half century ago-and partially revived in 1998 in a 19.5-ft version. The very latest Bambi, which debuts this month, isn't your Grandpa's trailer. More like a camper at 16 ft long and eight ft wide, this single-axle model has a tow weight of 3,500 lbs and weighs about 2,000 lbs when empty. "Anybody with a mini-van or large sedan can tow it," says Miner, who adds that it's actually shorter than most mini-vans. It will carry a price tag of under $20,000.

For those who designed it, the Bambi 16 represents a design problem at the intersection of marketing and engineering: How to appeal to younger consumers without changing Airstream's signature styling and aerodynamic performance? The company's engineers rose to the challenge with a design in which old meets new.

"Old" is embodied in Bambi's overall package. Airstream barely tinkered with the aerodynamic shape it has used for 70 years. "From the underbelly to the roof, there's not a flat surface anywhere," says Miner. The shape conforms well enough to existing Airstream models that the design team even used some of the same wind tunnel results from testing back in the 1970's. "The shape is virtually unchanged, so we believe those results are still valid," says Miner. Also unchanged is the Airstream monocoque, double-hulled aluminum construction-in which the wiring and insulation take up space between the walls. And the Bambi still uses the company's time-tested rubber torsion suspension system, which replaces the moving parts of a conventional shock absorber with stack of elastomeric bearings.

"New", meanwhile, appears in the many subtle changes that take weight and cost out of the Bambi 16 while making it less maintenance-intensive than larger trailers of the past.

Chassis developments. Starting from the ground up, Airstream's design team first came up with a new sectional frame for the Bambi 16. Made entirely from formed steel components joined by a fastening system from Huck Inc. (Waco, TX), this new frame represents a major departure from the welded structural steel construction Airstream uses on its other trailers. The Bambi 16 consists of three main sections-a center suspension section, a front section with an a-frame leading to the tow vehicle, and a rear section.

The new frame style, inspired by European trailer designs, offers some compelling advantages, according to Bob Foley, Airstream's director of engineering. For one thing, it weighs about 20% less than a welded frame of the same size. It also costs about 30% less. At the same time, he adds, it's every bit as strong. "We form the strength into the frame," he says, pointing to ribs and other integrated structural elements.

And because its sections are modular, larger two-axle Bambi models will be able to share frame elements with the Bambi 16. Creating a chassis for a larger double-axle model would require only an additional suspension section, Foley says.

For corrosion resistance, Airstream's engineers choose an e-coat process rather than the hot-dip-galvanizing used by European manufacturers. "We found cost problems with galvanizing," Foley explains. "But our frame supplier already had e-coat capabilities in house."

Cabin design. Airstream engineers identified even more weight and cost saving opportunities inside the cabin. "We took out a lot of overdesign" says Foley. And they did so by putting in more plastics.

Foley reports Airstream replaced metal galvanized parts with ones thermoformed from ABS and PE in areas that don't interfere with Airstream's signature aluminum styling. "We put the plastic in places you can't see it," Foley says, citing wheel wells, holding tanks and covers as the first parts to undergo conversion to plastics. While not in place yet, the company may also add a thermoformed shower surround to replace fiberglass. All the new plastic components forced Airstream engineers to embrace solid modeling on a larger scale than any past project. "Every new component was modeled in Mechanical Desk- top," Foley reports.

The new Bambi's small size also let the designer adopt a one-piece oriented strandboard floor, which replaced more costly tongue-and-groove flooring. "Getting the seams out gets the cost out," Foley says. Vinyl tiles in the new Bambi take the place of heavier carpet in past models.

Other aspects of the interior remain the same as previous Airstreams, though many of the appliances and systems have been scaled down to fit the smaller space. In some cases, though, this downsizing contributed to further weight and cost savings. For instance, the new Bambi employs direct discharge furnace that eliminates the need for ductwork under cabinets.

User friendly. Given the age of the buyers Airstream is courting, the Bambi's designers sought to maximize creature comforts. The Bambi is pre-wired for sound, solar power, portable satellite, and telephone hook-ups. And it can optionally carry an air conditioner. Since some of these hallmarks of digital civilization need to mount on the roof, the trailer retains the load-bearing top of its larger predecessors.

It also has been engineered for low maintenance with details such as smaller, quick-mounting LP bottles and a simplified "wet bath" for easier cleaning. To keep exterior maintenance to a minimum, the trailer employs a fluoropolymer clearcoat from PPG Industries (Pittsburgh). According to Miner, the coating, which Airstream has not used in the past, helps the Bambi retain its shine without much work. "All it needs is a wash and wax," he says, noting that the Bambi can even be run through a typical car wash. And accelerated weathering tests show that the clearcoat lasts long enough for Airstream to bump up its warranty on the exterior from 12 months to 3 years, Miner adds.

Coupled with the weight and cost cuts, low maintenance completes the picture of a trailer that's always ready to leave its little spot of driveway and hit the road, says Miner. "Just hop in and take off."

Airstream survival stories

Airstream's renowned aerodynamic shape means more than good handling and savings at the gas pump. It may mean the difference between life and death in the event that severe weather or an unexpected nuclear holocaust interfere with your driving vacation.

Consider, for example, the threat of hurricanes. Product development manager Miner points to instances of Airstream trailers sitting firmly in place while heavy winds launched much larger mobile homes on a trip to Oz. And not to be outdone in the what-else-could-go-wrong department, Director of Engineering Bob Foley speaks of an Airstream's brush with nuclear destruction during early atomic bomb tests. "It was parked just 10,500 feet from ground zero, and all that happened to it was broken windows and dents," he says. Whether the trailer later glowed, Foley doesn't know.

True tales of RV survival or just folklore? You be the judge.

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