Narrative:

[I was] performing line check from jumpseat. During initial taxi out from ord gate; captain made a left turn out and did not observe an rj approaching from left on taxiway a. I observed the aircraft approaching at high speed; and called for captain to stop. The captain; now seeing the conflict made an abrupt stop. The crew then reaffirmed their taxi clearance as ATC had not mentioned any traffic to follow on initial clearance. Crew continued taxi out and confirmed that flight attendant's and passengers were okay. Later in the flight the purser claimed that she may have experienced an injury and would be filing a report. The rest of flight was uneventful.

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Original NASA ASRS Text

Title: B757 flight crew was cleared to taxi from their pushed back position to Runway 22L via Taxiway A. As the aircraft began to move the Check Airman on the jump seat sights a fast moving RJ from the left rear and commands a stop.

Narrative: [I was] performing Line Check from jumpseat. During initial taxi out from ORD gate; Captain made a left turn out and did not observe an RJ approaching from left on Taxiway A. I observed the aircraft approaching at high speed; and called for Captain to stop. The Captain; now seeing the conflict made an abrupt stop. The crew then reaffirmed their taxi clearance as ATC had not mentioned any traffic to follow on initial clearance. Crew continued taxi out and confirmed that Flight Attendant's and passengers were okay. Later in the flight the Purser claimed that she may have experienced an injury and would be filing a report. The rest of flight was uneventful.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.