PRESTON, UNITED KINGDOM - Test NDT International recently completed a specialized training program for Czech Airlines to familiarize the inspectors with phased array concepts and the operating principles of a phased array instrument, in addition to introducing the inspectors to a new wing skin corrosion inspection using the phased array instrument.
Czech Airlines is one of the first airlines to implement this new procedure. This is a relatively recent ultrasonic phased array inspection requirement that was issued in June 2009 and uses the Olympus OmniScan phased array instrument in conjunction with the Sonatest 'Rapid Scan' wheel probe. The inspection uses a combination of an A-scan and double C-scan display formats to facilitate the detection and depth quantification of corroded areas on the upper wing skin.
The A-scan is used for initial setting up purposes and also for evaluation purposes. One C-scan is optimized for the detection of loss of back-wall echo amplitude which occurs in the corroded area and this will be indicated by a darkening of the image in the upper C-scan. The second C-scan is set up to monitor remaining material thickness in the area and will be seen as a change in color of the second C-scan.
If the thickness values are set correctly on the OmniScan, the uncorroded material will appear as a bright blue and the corroded areas will appear as different colors and shades. The thickness values can be adjusted so that when the maximum permitted corrosion loss has occurred, the color will turn red.
Test NDT International is based in Preston, United Kingdom, and has been one of the original training partners in the Olympus NDT training academy since it was established in 2005. Test NDT specializes in training for aircraft phased array and eddy current array applications. This training course is the latest in a series of specialised training courses developed by Test NDT to assist airline operators in implementing new phased array and eddy current array (ECA) inspection applications.
Other array applications already covered by TEST NDT are the Boeing scribe line phased array procedure and the Boeing 737 lower fuselage eddy current array procedures, in addition to various carbon fiber composite-based training courses.
For 2010, in addition to the phased array and eddy current array scheduled courses, TEST NDT will also be offering a range of Level 1 and 2 ultrasonic and eddy current courses for aircraft inspectors. There will also be Level 3 refresher training courses in all major methods.