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Title: NDE of Damage in Aircraft Flight Control Surfaces

Abstract

Flight control surfaces on an aircraft, such as ailerons, flaps, spoilers and rudders, are typically adhesively bonded composite or aluminum honeycomb sandwich structures. These components can suffer from damage caused by hail stone, runway debris, or dropped tools during maintenance. On composites, low velocity impact damages can escape visual inspection, whereas on aluminum honeycomb sandwich, budding failure of the honeycomb core may or may not be accompanied by a disbond. This paper reports a study of the damage morphology in such structures and the NDE methods for detecting and characterizing them. Impact damages or overload failures in composite sandwiches with Nomex or fiberglass core tend to be a fracture or crinkle or the honeycomb cell wall located a distance below the facesheet-to-core bondline. The damage in aluminum honeycomb is usually a buckling failure, propagating from the top skin downward. The NDE methods used in this work for mapping out these damages were: air-coupled ultrasonic scan, and imaging by computer aided tap tester. Representative results obtained from the field will be shown.

Authors:
; ;  [1]
  1. Center for Nondestructive Evaluation, Iowa State University, Ames, IA 50011 (United States)
Publication Date:
OSTI Identifier:
21054984
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2718073; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AIRCRAFT; ALUMINIUM; CONTROL; DAMAGE; DEFECTS; DETECTION; FIBERGLASS; FRACTURES; MAINTENANCE; MAPPING; MORPHOLOGY; NONDESTRUCTIVE TESTING; SURFACES

Citation Formats

Hsu, David K., Barnard, Daniel J., and Dayal, Vinay. NDE of Damage in Aircraft Flight Control Surfaces. United States: N. p., 2007. Web. doi:10.1063/1.2718073.
Hsu, David K., Barnard, Daniel J., & Dayal, Vinay. NDE of Damage in Aircraft Flight Control Surfaces. United States. doi:10.1063/1.2718073.
Hsu, David K., Barnard, Daniel J., and Dayal, Vinay. Wed . "NDE of Damage in Aircraft Flight Control Surfaces". United States. doi:10.1063/1.2718073.
@article{osti_21054984,
title = {NDE of Damage in Aircraft Flight Control Surfaces},
author = {Hsu, David K. and Barnard, Daniel J. and Dayal, Vinay},
abstractNote = {Flight control surfaces on an aircraft, such as ailerons, flaps, spoilers and rudders, are typically adhesively bonded composite or aluminum honeycomb sandwich structures. These components can suffer from damage caused by hail stone, runway debris, or dropped tools during maintenance. On composites, low velocity impact damages can escape visual inspection, whereas on aluminum honeycomb sandwich, budding failure of the honeycomb core may or may not be accompanied by a disbond. This paper reports a study of the damage morphology in such structures and the NDE methods for detecting and characterizing them. Impact damages or overload failures in composite sandwiches with Nomex or fiberglass core tend to be a fracture or crinkle or the honeycomb cell wall located a distance below the facesheet-to-core bondline. The damage in aluminum honeycomb is usually a buckling failure, propagating from the top skin downward. The NDE methods used in this work for mapping out these damages were: air-coupled ultrasonic scan, and imaging by computer aided tap tester. Representative results obtained from the field will be shown.},
doi = {10.1063/1.2718073},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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