Location

Snowmass Village, CO

Start Date

1-1-1995 12:00 AM

Description

Weep holes are drilled through risers in wet-wing structures in order to permit remanent fuel to be evenly distributed during flight. Unfortunately, they can become the sites from which fatigue cracks tend to originate. Figure 1 shows the schematic diagram of weep holes cut into the vertical risers of an airplane wing used as a fuel tank. The cracks have been found to grow in either the upward or downward or both directions. These fatigue cracks initially grow in a radial direction perpendicular to the wing skin surface. Downward growing cracks can be easily detected using a 45-degree shear wave transducer. The main objective of this study was the development of an ultrasonic detection technique for the less accessible upward growing cracks. The blowup in Figure 1 shows the geometrical configuration of such an upward growing fatigue crack.

Volume

14B

Chapter

Chapter 7: Materials' Degradation and Specific Applications

Section

Fatigue Damage and Crack Characterization

Pages

1963-1970

DOI

10.1007/978-1-4615-1987-4_251

Language

en

File Format

application/pdf

Share

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Jan 1st, 12:00 AM

Weep Hole Inspection for Radial Fatigue Cracks by Circumferential Creeping Waves

Snowmass Village, CO

Weep holes are drilled through risers in wet-wing structures in order to permit remanent fuel to be evenly distributed during flight. Unfortunately, they can become the sites from which fatigue cracks tend to originate. Figure 1 shows the schematic diagram of weep holes cut into the vertical risers of an airplane wing used as a fuel tank. The cracks have been found to grow in either the upward or downward or both directions. These fatigue cracks initially grow in a radial direction perpendicular to the wing skin surface. Downward growing cracks can be easily detected using a 45-degree shear wave transducer. The main objective of this study was the development of an ultrasonic detection technique for the less accessible upward growing cracks. The blowup in Figure 1 shows the geometrical configuration of such an upward growing fatigue crack.