described The ultrasonic technique used for the examination is based on modern ultrasonic flaw detectors Using a rail-inspection train railroads are continuously checked for traffic-induced defects because high train speeds
and heavy axle loads are the critical factors affecting the service life of the rails Up to the present time only ultrasonic
inspection was used In addition eddy-current inspection could successfully and efficiently be used to detect and
evaluate certain surface cracks—so-called head checks. There have already been reports about laboratory tests which
proved the general suitability of this test method [12,13] The next step—described here—consisted of practical trials
under real-life conditions Atest systemthat is able to fulfil the strict requirements (test speeds of up to 100 km/h complex
probe guidance suppression of electrical and mechanical interference, recording of data filtering and evaluation of
data) was developed As part of the rail-inspection train and as a manual system this inspection system was successfully
tested on railroads under real conditions