Sensors for Critical Fault Location for Aging Wire Networks

美国国家运输安全委员会、联邦航空管理局、航空飞行员协会和海军空战司令部已将老化的飞机布线确定为当今航空面临的最重要的安全问题之一。线路故障被认为是导致环球航空800航班和瑞士航空111航班坠毁的原因。数十起其他坠机事件(商业和军事)也与线路故障有关。美国国家航空航天局、核管理委员会、消费品安全委员会、国家火车协会、美国空军、陆军、海军和海岸警卫队以及国家科学基金会参加了白宫委员会对布线的联合审查，将其确定为立即引起国家关注的关键领域。尽管问题严重，但检查布线以防止严重事故的技术非常有限。飞机布线的目的是在没有重大维护或检查的情况下使用飞机的寿命(最初假设为10-15年)，因此被“内置”在飞机机身中，极难检查或更换。商用飞机现在的平均机龄为18年，军用飞机的平均机龄为16年。检查飞机布线最常见的方法是目视检查常见的故障点，寻找针头大小的裂缝或断裂。另外两种方法--阻抗/连续性测试和时域反射仪--需要连接/断开电线才能进行测试，它们被怀疑造成了比预防更大的损害。

The National Transportation Safety Board, the Federal Aviation Administration, the Aviation Pilots Association, and the Naval Air Warfare Command have identified aging aircraft wiring as one of the most significant safety issues facing aviation today. Faulty wiring is believed to have caused the TWA Flight 800 and Swiss Air Flight 111 crashes. Dozens of other crashes (commercial and military) have been related to wiring faults as well. NASA, the Nuclear Regulatory Commission, the Consumer Product Safety Commission, the National Train Association, the US Airforce, Army, Navy, and Coast Guard, and the National Science Foundation participated in a joint review of wiring for the White House Commission, identifying it as an area of immediate critical national concern.In spite of the severity of the problem, the technology to inspect the wiring to prevent serious accidents is very limited. Aircraft wiring was meant to last the life span of an aircraft (originally assumed to be 10-15 years) without significant maintenance or inspection, so is "built into" the aircraft body and is extremely difficult to inspect or replace. Commercial aircraft now average 18 years old, and military aircraft average 16 years old. The most common method of inspecting aircraft wiring is visually checking common failure points looking for cracks or breaks the size of the head of a pin. Two other methods -- impedance / continuity testing and Time Domain Reflectometry require connecting/disconnecting wires in order to test them and are suspected of causing more damage than they prevent.