The blade was cut into three sections for ease of shipping. Figure 4 shows a delamination in the leading edge of a blade section, whilst Figure 5 shows another section of the blade with three delaminations on the rib region. We have outlined the sub-structures on the record for the sake of clarity. The real problem here lays in the fact that there is a sharply curved leading edge, with a non-constant curvature and of varying stiffness, which radically affecting the relaxation frequencies as the analysis progresses round the curve. We are currently attempting to apply this new technology to both the detection and quantification of corrosion in aluminum structures such as lap joints found in the aerospace industry.
Corrosion is a serious problem in air transport fleet which is rapidly aging.
The average age of fleet aircraft is over seventeen years4. For example the Concord is now over 20 years old. There is a need for a technique both for the rapid and efficient detection of corrosion and its quantification in terms of metal losses. Our NDT technology was applied to an aluminum lap joint obtained from a Boeing 707 aircraft. The image is a composite of several groups of frequencies.