Airline Evidence

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The NTSB (National Transportation Safety Board) is tasked with investigating any kind of transportation accident.  One of the most visible aspects of this is airline crashes and collisions.

Forensic investigators must use multiple types of evidence to determine not only the cause of the crash, but the sequence of events that led to the accident.

Types of evidence used by crash investigators

• FDR (Flight Data Recorder)--monitors the planes altitude, attitude, speed, heading, and cockpit instruments

• CVR (Cockpit Voice Recorder)--monitors the conversation between the pilot, copilot and navigator

Both of these are designed to survive most crashes.

• Location and condition of seats

  • Example: If the front of the seats are burned, then the passenger must have been thrown from the seat before the fire erupted

• Condition of passengers (both those that survive and those that perish)

  • Example: In a water crash, passengers that have fallen from a high altitude will generally be found unclothed (the force of the entry into the water usually rips the clothing from a human body)

• Condition of aircraft (scorching of metal, bending of metal)

  • Example:  Scorched and bent metal can indicate a high intensity explosion

Case Study: TWA Flight 800

The TWA flight 800 went down off Long Island  only a few minutes after take-off.  Witnesses stated that they saw a fireball in the sky which fell to Earth.  The NTSB was called in to examine the wreckage and determine the cause of the accident.  Unfortunately, the wreckage happened to fall into one of the deepest parts off Long Island.  Pieces of the aircraft lay in water up to 200 feet deep and scattered over  an area measured in square miles.  The depth of the wreckage limited the NTSB's ability to easily determine the sequence of events that led to the crash.  Because of this "lack of information," the media and others began speculating about what might have caused the crash.  Three  distinct theories began to surface.

• A terrorist bomb in the cargo hold

• A fuel tank rupture and explosion

• A missile from a U.S. warship

Investigators from the NTSB began retrieving pieces of the aircraft from the bottom of the Atlantic.  Because of the enormous number of pieces, NTSB investigators realized that the best way to identify the cause of the crash was to rebuild the aircraft in a large hanger.

Interesting Evidence:

1.    No significant bomb residue

2.    No significant scorching of the metal

3.    No fragments of extraneous devices found in the aircraft

4.    No fragmentation of bodies near the explosion

5.    Some seat fronts were burned

6.    Backs of some bodies have chemical burns similar to fuels used in aircraft and missiles

7.    Some bodies recovered without clothing

8.    Very little metal fragments of the aircraft found in passengers nearest explosion

 

Final conclusion:  Centerline fuel tank exploded causing fireball and break of aircraft