NDT Technology

NDT Technology

Inspection of flight control surfaces made by honeycomb sandwich panels with use of Thermography method and Air Injection

Document Type : Original Article

Abstract
Abstract
Usage of composite materials in aircrafts is increasing because of lightweight, strength and other appropriate physical properties. Vertical Rudder and Horizontal Elevator usually made by Honeycomb composite sandwich panels. These surfaces may be affected by defects due to crossing different climatic conditions and aging. In addition, detection of accumulated water droplets is so important. Although the using of conventional nondestructive inspection test methods such as Ultrasonic is so common, but concerning the restrictions, would not be enough. Checking for the changes of elastic properties cannot lead to the detection of water droplets in the internal network and defects too. The most common way to ensure the absence of these defects is using the Thermography method. Thermography is based on the specific thermal properties of materials and thermal equilibrium point. Airbus has used the two methods of Lock-in Thermography and Pulse Thermography in order to inspect possible defects in Rudders and Elevators.
As well as describing the inspection principals in using this method, the current article studies the possibility of using the Air Injection for inspecting these surfaces.
Keywords

1- Sala G (2000). Composite degradation due to fluid absorption, Elsevier, Vol. 31, no. 5.
2- Kumar, M. S., (2012). Fractographic analysis of tensile failures of aerospace grade composites, Materials Research, ISSN 1516-1439, vol.15, no.6.
3- Structural Repair Manual (A300-600), Airbus.
4- Matzkanin, G. A. (1995). Nondestructive Characterization of Heat Damage in Graphite/Epoxy Composite, A State-of-the-Art Report, Texas Research Institute, Austin, TX. (1996) Unraveling- The secrets of composite structures repair, New Technology, AEM/July.
5- Singleton Holden, E., (2007). Sir William Herschel: His Life and Works, Kessinger Publishing
6- Nondestructive Testing Manual; PART 10, (2016). Thermographic, A321, Chapter 55-40-50 Rev. 108,
7- Standard Test Method for Min. Resolvable Temperature Difference for Thermal Imaging Systems, (2009). ASTM E1213,
8- Nondestructive Testing Manual, Part 10, (2016). Thermographic, A300-600 Chapter 55-20-08 & 55-20-11.
9- Infrared and Thermal Testing, Nondestructive Testing Handbook, ASNT, 3th edition, (2001), Vol. 3.
10- Licentiate Thesis, INFRARED EMITTANCE OF PAPER METHOD DEVELOPMENT, MEASUREMENTS AND APPLICATION, The Royal Institute of Technology, Stockholm, NOVEMBER 2012, Caroline Hyll,
11- Standard Practice for Infrared Flash Thermography of Composite Panels and Repair Patches Used in Aerospace Applications, (2007). ASTM, E 2582.
Volume 2, Issue 4 - Serial Number 5
September 2019
Pages 21-31

  • Receive Date 03 June 2018
  • Accept Date 11 August 2019