NDTnet 1998 Aug, Vol.3 No.8

Full-Text - Abstract

Thermal wave imaging can be used to determine aircraft skin corrosion thinning.[1] In addition to imaging the pattern of subsurface corrosion, the technique can rapidly (a few seconds) make quantitative measurements of less than 1% material loss for various regions in the image. It uses pulse heating of the aircraft from photographic flashlamps mounted in an aluminum box, open at one end and placed against the fuselage of the airplane. This box traps and funnels the light uniformly onto the fuselage, and an infrared (JR) focal plane array camera, aimed and focused at the surface through an opening in the rear of the hand-held shroud, monitors the rapid cooling of the surface of the fuselage. Metal doublers, bonded to the inside surface of the fuselage, cause the outside surface just above them to cool more rapidly, whereas regions which are thinned because of internal surface corrosion cool less rapidly. An example thermal wave image of both bonded and disbonded doublers on a 747 aircraft is shown in the illustration below.

Fig. 1: EXAMPLE OF BONDED & DlSBONDED DOUBLERS ON A B747 AIRCRAFT

Acknowledgments
This material is based upon work performed by the FAA-Center for Aviation Systems Reliability, operated at Iowa State University and supported by the Federal Aviation Administration Technical Center in Atlantic City, New Jersey, under grant number 95-G-025, and by AFOSR under Grant No. F49620-96-1-0166.

Reference
1. Han, Xiaoyan, Favro, L.D., Ahmed, T. Ouyang, Zhong, Wang, Li, Wang, Xun, Zhang,Feng, Kuo, P.K., and Thomas, R.L., Review of Progress in Quantitative NDE, Vol. 16,_edited by D.O. Thompson and D. Chimenti, Plenum New York, pp. 353-356 (1997)._

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

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