Interpretation ID: aiam0229
49 Roseland Street No. 3
Cambridge
Ma. 02140;
Dear Mr. Hemenway: Thank you for your letter of March 9, 1970, addressed to the Nationa Highway Safety Bureau, concerning the data provided pursuant to the Consumer Information regulations, 49 CFR S 575.101, Vehicle Stopping Distance. A copy of the consumer information data for 1970 vehicles is enclosed.; You asked whether stopping distances greater than 194 feet for vehicle traveling 60 mph indicate the likelihood that such vehicles are failing to meet Federal Motor Vehicle Safety Standard No. 105. As you have noted, the stopping distance for a constant 20 fpsps deceleration from 60 mps would be 194 feet. However, Standard No. 105 does not require an *average* deceleration rate (including 'lag' or 'build up' time) of 20 fpsps during the entire period of deceleration. The Standard requires only that a vehicle *attain* a deceleration rate of 20 fpsps, with a pedal force of between 15 and 120 lbs., in a stop from 60 mps. Consequently, the Standard does not require that the stopping distance not exceed 194 feet, and consumer information data showing a stopping distance is excess of 194 feet for the 60 mph test does not indicate non-compliance with Standard No. 105.; The attached Discussion Paper indicates some of the revisions i Standard No. 105 that are under consideration. Should amendments be found desirable, a notice of proposed rule making containing then proposed revisions will be issued.; Thank you for your interest in motor vehicle safety. Sincerely, Rodolfo A. Diaz, Acting Associate Director, Motor Vehicl Programs;