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Show DON'T S'KID YOURSELF Winter Tests Indicate Chains Are Safer Than New Safety Tires There has been an alarming upswing In traffic accidents during recent re-cent years. And the most disturbing aspect of the highway accident picture, according to the automotive safety foundations, is the mounting mount-ing ratio of rural fatalities. Excessive speed and inadequate control iby police and the courts are cited as the underlying factors in last year's !record, showing rural traffic deaths outnumbering urban fatalities by 'about two and a half to one. Winter, the most dangerous sea- son of the year on American highways, high-ways, is in full force throughout the nation. Highways in many areas have never been so dangerous. How slippery and dangerous is an icy road compared to a snowy one? Iow safe are "winter" tires? How do they actually compare with tire chains? In an effort to answer these and other important questions for the benefit of the puzzled motorist, the National Safety Council's committee commit-tee on winter driving hazards conducted con-ducted a two-week series of tests at Pine Lake, near Clintonville, Wis., (last winter. Results are now -m-fliiled and are being made public for the first time. 2,000 Tests Run Nearly 2,000 individual test runs were made to test 22 representative itread designs of various tires for stopping, "go" traction, and cornering corner-ing ability on snow and ice. The special spe-cial "winter" tires fall into three classifications: (1) Those with specially spe-cially impregnated treads containing :"breakout" material such as sawdust, saw-dust, peanut shells or rock salt: pothers have steel wool, chips or steel coils embedded which is intended to be "abrasive"; (2) surface treatment treat-ment consisting of multiple lacera-jtions, lacera-jtions, knife or saw cuts, and (3) various shapes of knobs, studs, lugs or ribs. All are supposed to give surer footing on the variety of slick or impassable surfaces encountered by winter drivers. Ross G. Wilcox, traffic engineer en-gineer for the National Safety Council, in summarizing the results, re-sults, said that in general, while the performance of some of the specialized tires showed a definable def-inable Improvement for some specific conditions over regular tires, their over-all improvement improve-ment was not great enough to warrant less care or elimination of tire chains when driving on Blippery surfaces. "As an example, the stopping distance dis-tance on glare ice of the best specialized spe-cialized tire tested is still about eight times the stopping distance on dry concrete," Wilcox said. "We found that steel tire chains of the reinforced type are far superior su-perior to the best of the special winter tires tested on snow and ice, and show a consistent improvement over conventional natural rubber tires averaging 46 per cent in stopping stop-ping ability, and 475 per cent in tractive ability." The tests also showed, he said, that natural rubber is 10 per cent to 50 per cent superior to cold synthetic syn-thetic rubber in stopping and traction trac-tion on snow and ice, although synthetic syn-thetic is about 7 per cent superior to natural rubber in cornering speed (resistance to side skids) on ice. Most passenger car tires in use today, to-day, and those now being manufactured manu-factured have treads that are all or part "cold synthetic rubber," which wears better. Truck tires need and do have more natural rubber. Tests Summary Averaging test results of all types on both glare ice and loosely packed snow, both for stopping, turning, and forward traction ability, the engineers en-gineers established a system of "rating" the over-all performance of each type of equipment. In all cases comparisons were made with a convention rib type tread of natural natu-ral rubber, or a duplicate tread of cold synthetic. Results of the conventional con-ventional natural rubber tread were considered the standard or baseline for comparative purposes and it was rated at 100. Use tire chains on Ice and snow. They cut braking distances dis-tances on cars and trucks 40 to 70 per cent and provide needed "go" traction. E-en with definite def-inite help of chains, careful driving is necessary. |