Abstract: A maintenance vehicle and associated method for measuring and correcting the level of a railroad track in a single pass. An instrument carriage, or frog, is towed by and in fixed relationship to the maintenance vehicle. The frog carries at least one inclinometer to measure at least one of longitudinal level and crossfall. As the vehicle periodically stops to work the track e.g. tamping or stoneblowing), the inclinometers are provided with the settling time necessary for accurate readings. In an additionally disclosed method, the track is measured and modeled prior to working using a primary measurement system and is then measured and modeled a second time while the track is worked using the frog.

Abstract: The specification discloses an improved railroad track curve liner for more accurately locating track transition points to more accurately calculate an improved track configuration as a funcion of the existing track configuration. The curve liner is mounted on a track tamper. During a first pass over the track, the curve liner acquires track ordinate information. After calculating the ideal track configuration, the tamper laterally shifts the track to the ideal configuration in a second pass over the track. The improved track configuration is calculated in recognition that the ordinate graph is not linear in all areas--particularly at tract transition points.