49 CFR 229.117 - Speed indicators.
(a) After December 31, 1980, each locomotive used as a controlling locomotive at speeds in excess of 20 miles per hour shall be equipped with a speed indicator which is—
(1) Accurate within ±3 miles per hour of actual speed at speeds of 10 to 30 miles per hour and accurate within ±5 miles per hour at speeds above 30 miles per hour; and
Title 49 published on 2013-10-01
no entries appear in the Federal Register after this date.