If you have ever leaned back comfortably in a chair — only to feel that sudden sensation of falling suddenly rearward out of control, you know what I’m talking about. It’s that moment when your general sense of control is swept away and you experience those indiscriminate principles of physics take the lead. The same feeling comes over us when we are driving our cars over rain-soaked roads — and in an instant we can sense that our tires have lost traction with the pavement. On snow or ice-covered highways we’re more inclined to anticipate that potential loss of control. Yet, most of us are caught off-guard when our cars “hydroplane” over wet roads.
The Obstacle: “Hydroplaning”
Full-fledged hydroplaning of your tires is similar to what happens in recreational water skiing. Moving slowly through the water with your skis attached, you’ll sink. But when you’re pulled through the water at faster speeds, the skis will ride up progressively higher — until you’re ultimately gliding across the top of the water. That experience is a fun one. Back in your car, when your wheels hydroplane it can result in a complete loss of steering and braking control and result in life-threatening consequences.
A car’s speed plays a major role in its hydroplaning, although it can occur at speeds as low as 45 mph on curves. Water must have time to flow into and out of tire tread grooves. At high speeds, there is less time for the tire to “unload” the water — and that’s when trouble starts. Driving in the rain is certainly a design factor in all passenger car and truck tires. Yet, at the same time tires must balance a variety of engineering and driving priorities to serve our needs. In years past, most tire technology emphasized the performance considerations for dry-weather driving — since that is the predominant anticipated driving use.
Consequently, most conventional tire designs exhibit carefully engineered compromises to deliver good overall driving in the areas of tread wear, durability and traction — along with anticipation for occasional wet weather driving use.
Yet, just as our new cars and trucks exhibit dramatically improved technology and driving performance today, tires have been evolving, as well. Goodyear was one of the first tire companies to develop a revolutionary tire specifically designed to deliver superior wet-weather traction performance while retaining comprehensive dry-weather perfomance characteristics. Goodyear calls the advanced new tire the Aquatred.
When Goodyear engineers invented Aquatred, they were looking for a new and exciting tire for family car customers. And stopping on rain-slick roads wasn’t the primary marketing consideration — at least initially. Goodyear’s goal was to simply introduce an improved tire that was “new and exciting.”
In 1989, Goodyear’s marketing staff asked the company’s engineers to create a new tire to set it apart from the competition. The new tire, code named “Newex” (for new and exciting), evolved from a prototype tire that had previously been used for General Motors’ Aero concept car at Disney’s Epcot Center in Florida.
The Aero’s Goodyear concept tires were the first to introduce an “aquachannel” tread. The aquachannel is a deep center groove that literally pumpswater from beneath a tire for improved levels of stopping performance and wet-weather traction.
The aquachannel idea was similar to that of a twin tire, with a void in the center of the tire footprint and higher contact pressure on each tire half. The Newex/aquachannel tire was accepted as a revolutionary design concept. And thanks to the technological convergence of new powerful tire engineering computer software, new methods of tire production and molding along with a new wet-traction rubber compound, the design became feasible.
Test engineers used sophisticated glass plate photography and Goodyear’s exclusive Pressure Analysis System to perfect the Newex tread design.
The Pressure Analysis System measures pressure changes across the tire’s “footprint” to identify the lowest pressure points of the contact area — where water could separate the tire from the road. By optimizing the design of the aquachannel around these areas, Goodyear engineers were able to increase water removal without compromising other tire performance features.
Following this extensive product testing and refinement, a new passenger car tire was born and Goodyear changed its code named Newex to the “Aquatred.”
Next, Goodyear marketers asked the ultimate question, “Would anyone pay a premium price for a tire that delivers superior wet traction for a family car?” Well, that question was quickly answered in the marketplace when Goodyear sold one million Aquatred tires in its first year. The original 1992 sales estimate was 850,000.
Initially available in six tire sizes, Aquatred has blossomed into a variety of car and truck tire models for cars, light trucks and sport/utility vehicles today. In addition to the original Aquatred, Goodyear has subsequently introduced the Aquatred II. The Aquatred II offers the same wet traction benefits as the original Aquatred, but is backed by a 65,000-mile limited treadlife warranty, 5,000 miles more than the original aquatread.
Goodyear also introduced an Aquatred version of its Eagle high-performance tire (with dual aquachannels), a price-line version called “Intrepid” and the sport/utility and light truck tire called the “Wrangler Aquatred.”
Goodyear reports that the Aquatred tire with its “aquachannel” can pump up to a gallon of water per second from beneath the tire to achieve excellent wet-weather traction.
“So, it looks neat, sells well and all that. But do you guys have any actual performance testing results to report?” I asked Dave Wilkins, Goodyear’s public relations representative. He provided me with a statement from Sam Landers, Goodyear’s chief engineer of passenger car tires: “Thanks to its design, the tire uses up thirty percent more contact area on the road than other tires. On rain-slick roads, Aquatred-equipped automobiles with anti-lock brakes stop 20 percent sooner than on other family car tires.”
Goodyear also offered several driving tips for all types of tires — tips we can all use:
(1) When it rains, slow down, steer and brake with a light touch and have a good set of tires to resist water-skiing on four wheels (Hey, we know what Goodyear’s talking about here! It’s called hydroplaning), and (2) Be extra careful driving after fresh rain. Light showers and the early minutes of heavier rains can cause more skid than major storms, particularly after dry spells. Oil and grease accumulating on the roadway mix with rainwater to make the surface more slippery.