and spreadsheets to give managers a clear picture of the condition of the railroad. Even in 1981, the Encyclopedia of North American Railroads considered this the most advanced track geometry car in North America. Advantages Track inspection was originally done by track inspectors walking the railroad and visually inspecting every section of track. This was hazardous as it had to be done while trains were running. It was also manpower intensive, and inspectors were limited in the amount of track they could inspect on a given day. Manual instruments had to be used to measure various parameters of the track. The primary benefits of track geometry cars are the time and labor saved when compared to doing manual inspections of track. Track geometry cars may travel up to 217 miles per hour (335 kilometers per hour), inspecting track the whole time. More commonly, on freight railroads, geometry cars travel at track speed (up to 70 miles per hour) to minimize service disruptions. Current track geometry cars may cover large portions of the system in a single day. Many times, maintenance gangs will follow the geometry car and fix defects as the geometry car moves along the track. Because track geometry cars are full-sized rail cars (with the exception of some lighter hi-rail geometry cars), track geometry cars also provide a better picture of the geometry of the track under loading (compared to manual methods which did not consider this). Finally, track geometry data is generally stored and can be used to monitor trends in the degradation of track. This data can be used to pinpoint and predict trouble spots in the track and plan maintenance programs accordingly. Parameters measured The tolerances of each parameter varies by the track class of the track being measured. In the United States, geometry cars generally classify each defect as either "Class II" or "Class I" (though the exact name may vary by the railroad). A class II defect is known as a maintenance level defect, meaning that the track does not meet a particular railroad's own standards. Each railroad has their own standard for a maintenance level defect. A class I defect is a defect in violation of the Federal Railroad Administration's (FRA) track safety standards. Railroads must fix these defects within a certain period of time after their discovery or else they risk being fined. Alignment – "Alignment is the projection of the