The two objectives of this program are (1) to demonstrate that the non-destructive inspection process of SQUID (Superconducting Quantum Interference Device) magnetometry can locate cracks hidden in multiple-layered structures while operating in depot or field maintenance environments and (2) to produce and deliver to the government an ELECTROMAGNETIC MICROSCOPE that uses low-temperature superconductors for non-destructive inspection of calibration samples in the laboratory. Phase I of this program demonstrates that cracks hidden in multiple-layer structures, which simulate certain locations in a C-141 aircraft wing, can be located and measured by a laboratory brassboard SQUID magnetometer in a laboratory environment. Phase II will demonstrate that, with addition of mechanical jigs to control sensor head motion and support the instrument, cracks in an actual C-141 wing can be located and measured in depot and field maintenance environments without defueling the wing. Phase II will also produce a laboratory brassboard SQUID magnetometer for delivery to Warner Robins Air Logistics Center. This instrument, which will use low-temperature superconductor materials technology, will enable WR-ALC/TIE to perform its own experiments and development of NDI methods with SQUID magnetometry. This NDI instrument will prove useful both to the Air Force for inspections of it aging aircraft and to commercial aviation, which must inspect many of the same airframes used by the Air Force.
Benefits: If successful, this program will result in development of an NDI method which locate flaws hidden in multiple-layer airframe structures and provides enhanced digital records of inspections. This capability represents an important and useful advance to the following military aircraft: the Air Force's C-141, E-3, B-1B, and C-130 and the Navy's A-6 and F-14. In addition, commercial airlines, which fly many aircraft with identical or similar designs, would want to acquire the technology
