Share Email Print
cover

Proceedings Paper

Implementing recommendations of the Columbia accident investigation board: development of on-orbit IR thermography
Author(s): Brian P. Ottens; Bradford Parker; Ryan A. Stephan
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

One of NASA’s Space Shuttle Return-to-Flight (RTF) efforts has been to develop thermography for the on-orbit inspection of the Reinforced Carbon Carbon (RCC) portion of the Orbiter Wing Leading Edge (WLE). This paper addresses the capability of thermography to detect cracks in RCC by using in-plane thermal gradients that naturally occur on-orbit. Crack damage, which can result from launch debris impact, is a detection challenge for other on-orbit sensors under consideration for RTF, such as the Intensified Television Camera and Laser Dynamic Range Imager. We studied various cracks in RCC, both natural and simulated, along with material characteristics, such as emissivity uniformity, in steady-state thermography. Severity of crack, such as those likely and unlikely to cause burn through were tested, both in-air and in-vacuum, and the goal of this procedure was to assure crew and vehicle safety during re-entry by identification and quantification of a damage condition while on-orbit. Expected thermal conditions are presented in typical shuttle orbits, and the expected damage signatures for each scenario are presented. Finally, through statistical signal detection, our results show that even at very low in-plane thermal gradients, we are able to detect damage at or below the threshold for fatality in the most critical sections of the WLE, with a confidence exceeding 1 in 10,000 probability of false negative.

Paper Details

Date Published: 28 March 2005
PDF: 11 pages
Proc. SPIE 5782, Thermosense XXVII, (28 March 2005); doi: 10.1117/12.602828
Show Author Affiliations
Brian P. Ottens, NASA Goddard Space Flight Ctr. (United States)
Bradford Parker, NASA Goddard Space Flight Ctr. (United States)
Ryan A. Stephan, NASA Langley Research Ctr. (United States)


Published in SPIE Proceedings Vol. 5782:
Thermosense XXVII
G. Raymond Peacock; Douglas D. Burleigh; Jonathan J. Miles, Editor(s)

© SPIE. Terms of Use
Back to Top