SPURT Car - RDSO --- Self Propelled Ultrasonic Rail Testing Cars are equipped with automatic computerised system, is capable of detecting, analysing, locating various rail defects. It gives report of detected defects in a desired format. All rails and welds are ultrasonically tested as per laid down periodicity. This car tests both the rails while traveling up to 30 km/h. Most of the testing operations have been automated in this car. SPURT Car has water supply system with a capacity of 4000 litres guiding system for probe beam positioning and air system for lifting and lowering of probe. As SPURT car tests at higher speed, observation for flaws can not be done manually. Identification of defect is done electronically according to laid down logics. Also it has computer for tabulating, printing and storage of data. Tests around 80-120 track km per day. But the main flaws of these cars are that only ultrasonic information is available and severity classification is dependent on visual information. So classification is carried on the likely defective spots by the manual UFSD machines. For these cars repetition of test at a spot is also difficult due to speed and path constraint. And again the manual UFSD machines are in use. So Indian Railways used both these methods complementing each other as SPURT car short lists the likely defective spots and manual equipment is used to check only these locations. During this check the severity classification is done.