WRIGHT-PATTERSON AFB, Ohio—Engineers with the U.S. Air Force Research Laboratory Materials and Manufacturing Directorate (AFRL/RX) demonstrated a rarely-before-used pulsed thermography inspection technique while analyzing a cover failure in the GLOBUS II radar system.
The GLOBUS II radar in Vardo, Norway, is part of the 29-sensor global space surveillance network that tracks and identifies more than 10,000 man-made objects orbiting the Earth for U.S. Strategic Command at Offutt Air Force Base, Neb.
The radar is in a composite fabric shelter from St. Gobain, of Merrimack, N.H. The cover over the radar is inflated like a balloon. Nondestructive inspection (NDI) engineers used pulsed thermography to determine that bonding in previous repairs caused the cover failure.
Engineers decided to use a heavier and more durable Kevlar-based material for the radar shelter. Tests used a Themoscope II Pulsed Thermography inspection system from Thermal Wave Imaging Inc. in Ferndale, Mich.
“The system is comprised of an inspection hood containing an infrared camera and high-intensity flash lamps, connected directly to a ruggedized laptop computer,” says Kenneth LaCivita, the senior nondestructive evaluation engineer who went to Norway and trained teams to inspect the radar shelter.
“The inspection hood is placed directly onto the surface of the area of interest, heat is applied using the flash lamps, and real-time infrared thermal data (as fast as 300 frames per second) of the surface is collected, post-processed, and displayed on the laptop,” he says.
