Interpretation ID: aiam2913
Wesco Truck & Trailer Sales
P.O. Box 626
1960 E. Main Street
Woodland
CA 95695;
Dear Mr. Sambucetti: This responds to your October 30, 1978, request to know how th National Highway Traffic Safety Administration (NHTSA) expects a trailer manufacturer to provide the lateral stability necessary to remain within a 12-foot-wide lane while stopping from 60 mph in the absence of antilock installation. Your question follows from an interpretation of the recent Ninth Circuit ruling in which the agency stated its view that trailers are still required to stop from 60 mph within the 12-foot-wide lane, but without the capability of 'no lockup' performance.; In interpreting the court's ruling that 'no lockup' performance o trailers was invalid, the NHTSA recognized that the 12-foot-wide lane requirement would probably also be invalid if the requirement for 90 p.s.i. air pressure in the trailer control line during the stop remained effective. As you know, there is no stopping distance for trailers that would otherwise require a strong brake application and resulting loss of lateral stability. The agency therefore concluded that the 90 p.s.i. requirement was invalidated, stating in its October 19th interpretation,; >>>It does appear that the requirement for 90 p.s.i. air pressure i the trailer control line during the stop constitutes a portion of the 'no lockup' requirement and is therefore invalidated by the court.<<<; Sincerely, Joseph J. Levin, Jr., Chief Counsel