An Inside Look at TWA Flight 800

1397 Words3 Pages

1.0 Introduction

On July 17, 1996, Trans World Airlines flight 800, A Boeing 747-100, exploded and crashed into the Atlantic Ocean near New York 12 minutes after its departure. All 230 people on board died.

1.1 Accident Timeline

Although the flight was scheduled to depart from JFK Airport at about 7:00 p.m., it was delayed due to a disabled piece of ground equipment and concerns about a suspected passenger mismatch with baggage. The airplane took off at 8:18 p.m., shortly at 8:25 p.m., Boston air route traffic control center (ARTCC) instructed the pilots to climb and maintain an altitude of 19,000 feet and then lower down to 15,000 feet. However, at 8:26 p.m., Boston ARTCC amended TWA flight 800's altitude clearance, advising the pilots to maintain an altitude of 13,000 feet. At 8:29 p.m., the captain stated, "Look at that crazy fuel flow indicator there on number four... see that?" One minute later Boston ARTCC advised them to climb and maintain 15,000 feet to which the pilot replied: “Climb thrust”. After an extremely loud and quick sound, the cockpit voice recorder stopped recording at 8:31 p.m. At that moment, the crew of an Eastwind Airlines Boeing 737 flying nearby reported an explosion in the sky. TWA Flight 800 aircraft had broken up and crashed into the sea, 8 miles south of East Moriches, killing all on board. (1,2)

2.0 Accident Investigation

The Safety Board’s lengthy investigation revealed the possibilities of short circuiting wire systems as a source of ignition within the fuel tank, which would provide the minimum ignition energy required according to the parameters established by the American Petroleum Institute (API) as well as the analysis of the conditions within the CWT at the time of the incident. The he...

... middle of paper ...

...red testing at Lectromec showed that contaminants, such as water, lavatory fluid, and metal shavings, can create a bridge that can allow energy to unintentionally transfer between wires with cracked or damaged insulation for as long as 25 minutes without tripping circuit breakers. Specifically, the totalizer gauge’s wires on TWA Flight 800 had been improperly soldered together and had subsequently cracked apart, providing another opportunity for an explosive short circuit. During examination of the gauge at Honeywell, it was determined that electrical energy would cross the crack in the solder between the connector pins when slightly more than 270 volts (less than is used in lighting circuits) was applied to one of the pins. Thus, a short circuit from a higher-voltage wire to any corouted FQIS wiring could result in excess energy being transferred to the CWT.

Open Document