Shearographic Inspection of a Boeing 737
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Shearographic Inspection of a Boeing 737

Filetype[PDF-813.52 KB]


English
Details You May Also Like

Details:

  • Creators:
    Bobo, Stephen N.
  • Corporate Creators:
    John A. Volpe National Transportation Systems Center (U.S.)
  • Corporate Contributors:
    Federal Aviation Administration Technical Center (U.S.)
  • Subject/TRT Terms:
  • Publication/ Report Number:
  • Resource Type:
    Tech Report
  • Geographical Coverage:
    North Carolina
  • Edition:
    Technical note; Jul 1992
  • Corporate Publisher:
    Federal Aviation Administration Technical Center (U.S.)
  • NTL Classification:
    NTL-AVIATION-AVIATION;NTL-AVIATION-Aviation Safety/Airworthiness;
  • Abstract:
    Under a Cooperative Research and Development Agreement between VNTSC and Henson Aviation, Inc., operator of USAir Express, a shearographic demonstration inspection of the fuselage of a Boeing 737 aircraft was performed at a USAir repair station at Winston-Salem, NC, during August: 1991. The inspection compared the effectiveness of shearography with currently mandated methods in detecting disbonds in the fuselage. Adhesive bonding is utilized in modern aircraft fuselages, frequently in combination with rivets. As aircraft age, bond failure may become a major problem, since it may promote fatigue cracking, moisture intrusion, and subsequent corrosion. Any of these events may cause cabin pressure loss and, sometimes, catastrophic fuselage failure. The shearographic method of detecting disbonds depends on the deformation of the aircraft skin under varying pressurization. When illuminated by coherent light, the phase relationship and intensity of the light reflected from any two points of the skin changes as a result of this deformation. Surface changes down to 0.00025 millimeters can be detected and displayed as a real-time image of the field of view. Comparison of successive images as the pressure changes permits interpretation of the condition of a bond. For this demonstration, 31 disbonds were found by shearography; 25 were confirmed by ultrasound. Of the remainder, six were disbonds on structure where the Sondicator cannot perform reliably; one was a false positive; in addition, there was one Sondicator false positive confirmed by reference to a drawing and by observation. The demonstration indicated potential advantages of shearography over currently used inspection techniques, namely, improved reliability in the detection of disbonds in the fuselage and reduced down-time of the aircraft with concomitant reduced inspection costs.
  • Format:
    PDF
  • Collection(s):
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at rosap.ntl.bts.gov