NTSB ISSUES UPDATE ON INVESTIGATION INTO COLLISION OF TWO METRORAIL TRAINS IN WASHINGTON, D.C.

[NTSB Press Releases <NTSBPressReleases@xxxxxxxx>]

Title: NTSB ISSUES UPDATE ON INVESTIGATION INTO COLLISION OF TWO METRORAIL TRAINS IN WASHINGTON, D.C.

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                       NTSB ADVISORY
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National Transportation Safety Board
Washington, DC 20594

June 25, 2009

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NTSB ISSUES UPDATE ON INVESTIGATION INTO COLLISION OF TWO
METRORAIL TRAINS IN WASHINGTON, D.C.

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The National Transportation Safety Board continues to make
progress in its investigation of the June 22, 2009, accident
involving the collision of two Washington Metropolitan Area
Transit Authority (WMATA) trains on the Red Line in
Washington, D.C. The Board has developed the following
factual information:

Investigators found metal to metal compression streak marks
on both rails of the track for about 125 feet ending near
the approximate point of impact, consistent with heavy
braking.

Investigators conducted tests at the accident site last
night with a similar train and found that when the train was
stopped at the same location as the stopped struck train,
the train control system lost detection of the test train.

The train control system is complex and will require a
thorough investigation of all components. Investigators are
continuing to examine trackside circuits and train control
system data to understand how the train control system
functioned on the day of the accident.

Investigators have collected recorder data from the struck
train. Data was recovered from eight of the nine recorders
on the struck train. Data could not be downloaded from one
recorder. Two of the eight recorders did not contain data
related to the accident; data collection ended before the
accident for undetermined reasons. The accident data is now
being examined by investigators in the Safety Board's
laboratory. The striking train did not have any onboard
accident data recorders.

The operator of the struck train was interviewed earlier
today. He said that he operated his train in manual mode
during his entire shift that afternoon. He said that he saw
a train in front of him and stopped to wait for the train to
clear. While stopped, he said that he felt a hard push from
behind.

Investigators are continuing to document evidence at the
accident site and intend to conduct sight distance tests,
using similar trains to those involved in the accident.

Parties to the NTSB investigation include WMATA, the Federal
Transit Administration, the Amalgamated Transit Union, and
the Tri-State Oversight Committee.

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Media contact:
Bridget Ann Serchak
202.314.6100
bridget.serchak@xxxxxxxx
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