62. Alignment, in relation to uniformity, measured from an 18.9 m (62 ft.) chord may not exceed 12.7 cm (5 in.).
When the track is tangent, the ends of the chord must be placed at points on the gauge side of the rail, 1.59 cm (5/8 in.) below the top of the rail head. Either rail may be used, however, the same rail must be used for the full length of that segment.
When the track is curved, the ends of the chord must be placed at points on the gauge side of the outer rail, 1.59 cm (5/8 in.) below the top of the rail head.