Electromagnetic Interference - TWA Flight 800 Investigation

D. DETAILS OF THE INVESTIGATIONThe National Transportation Safety Board tasked the Naval Air Warfare Center –Aircraft Division, located in Patuxent River, Maryland to conduct a program investigatingtwo areas related to electromagnetic interference (EMI) and the accident involving TWAflight 800. The NAWC-AD was tasked to evaluate the following effects on the airplane:1) The effect of internally generated EMI from normal operation of aircraft systemson the fuel tank wiring;2) The effect of different electrical system configurations on the characteristics ofthe Captain’s channel of the cockpit voice recorder (CVR).Task 1 was designed to help determine if electromagnetic interference could have been athreat to the fuel tank wiring on the airplane, and task 2 was intended to help establishpotential electrical system configuration effects on the recorded signal of the CVR.The NAWC-AD prepared a report, dated June 12, 2000, which has been included asappendix A to this addendum.Scott WarrenAerospace Engineer