Mike Dinallo and Larry Schneider (left) prepare to use the PASD diagnostic on a wiring bundle in a retired Boeing 737 at Sandia. Photo by Randy Montoya.

Mike Dinallo and Larry Schneider (left) prepare to use the PASD diagnostic on a wiring bundle in a retired Boeing 737 at Sandia. Photo by Randy Montoya.


But a novel technique helps pinpoint potentially dangerous shorts hidden in the miles of wiring, say developers at Sandia National Laboratories. PASD (Pulsed Arrested Spark Discharge) sends a nanosecond pulse of electricity that can jump gaps in slightly frayed insulation, but lacks enough energy to harm electronics. A circuit analyzes time-of-flight of the current signal to locate faulty wires within inches.

The technique may make it financially feasible for airlines to quickly diagnose and repair hard-to-locate intermittent faults that have plagued the industry and cost millions of dollars in aircraft downtime.

Other potential applications for PASD include inexpensive tests for wiring in passenger cars and new homes. Military tanks and the hard-to-reach wiring behind bulkheads of submarines are also possible candidates.