Narrative:

Air carrier X cleared to land runway 4R short of runway 8L. After landing runway 4R, told to hold short runway 4L on kilo taxiway (note: kilo taxiway crosses both runways 4L and 8L at the same spot). Heard tower tell air carrier Y to change runway to 4L. Heavy widebody transport landing runway 8L. We came to a stop on kilo taxiway, set park brake. Tower then told us 'cleared to cross runway 8L, traffic clearing upfield, contact ground .9.' first officer repeated back cleared to cross runway 8L. We could see the widebody transport decelerating on runway 8L and looked down runway 4L, but could not see air carrier Y. Air carrier X taxied across runway 8L. While crossing tower tells air carrier Y, sorry about that, I don't know why he crossed (meaning us, air carrier X). First officer informed tower we were cleared to cross. Later ground control called us and said tower would like to apologize for the mix-up. I think this occurred due to the many new controllers and sitting on kilo taxiway, we do not have a complete view of runway 4L. At that angle it is impossible to see the approach end or touchdown zone. We looked carefully before crossing and saw no conflicting traffic -- or -- we would not have crossed. Also, it is standard practice that even though traffic has just landed and is not actually clearing the runway, we are told to cross -- traffic clearing. Not seeing air carrier Y, I assumed it to be either still on the final or clearing the runway. Instructions to cross at kilo are 99% of the time given as just cleared to cross runway 8L.

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Original NASA ASRS Text

Title: ACR X HAD LTSS SEPARATION FROM LNDG ACR Y WHILE XING RWY. SYS ERROR.

Narrative: ACR X CLRED TO LAND RWY 4R SHORT OF RWY 8L. AFTER LNDG RWY 4R, TOLD TO HOLD SHORT RWY 4L ON KILO TAXIWAY (NOTE: KILO TAXIWAY CROSSES BOTH RWYS 4L AND 8L AT THE SAME SPOT). HEARD TWR TELL ACR Y TO CHANGE RWY TO 4L. HVY WDB LNDG RWY 8L. WE CAME TO A STOP ON KILO TAXIWAY, SET PARK BRAKE. TWR THEN TOLD US 'CLRED TO CROSS RWY 8L, TFC CLRING UPFIELD, CONTACT GND .9.' FO REPEATED BACK CLRED TO CROSS RWY 8L. WE COULD SEE THE WDB DECELERATING ON RWY 8L AND LOOKED DOWN RWY 4L, BUT COULD NOT SEE ACR Y. ACR X TAXIED ACROSS RWY 8L. WHILE XING TWR TELLS ACR Y, SORRY ABOUT THAT, I DON'T KNOW WHY HE CROSSED (MEANING US, ACR X). FO INFORMED TWR WE WERE CLRED TO CROSS. LATER GND CTL CALLED US AND SAID TWR WOULD LIKE TO APOLOGIZE FOR THE MIX-UP. I THINK THIS OCCURRED DUE TO THE MANY NEW CTLRS AND SITTING ON KILO TAXIWAY, WE DO NOT HAVE A COMPLETE VIEW OF RWY 4L. AT THAT ANGLE IT IS IMPOSSIBLE TO SEE THE APCH END OR TOUCHDOWN ZONE. WE LOOKED CAREFULLY BEFORE XING AND SAW NO CONFLICTING TFC -- OR -- WE WOULD NOT HAVE CROSSED. ALSO, IT IS STANDARD PRACTICE THAT EVEN THOUGH TFC HAS JUST LANDED AND IS NOT ACTUALLY CLRING THE RWY, WE ARE TOLD TO CROSS -- TFC CLRING. NOT SEEING ACR Y, I ASSUMED IT TO BE EITHER STILL ON THE FINAL OR CLRING THE RWY. INSTRUCTIONS TO CROSS AT KILO ARE 99% OF THE TIME GIVEN AS JUST CLRED TO CROSS RWY 8L.

Data retrieved from NASA's ASRS site as of July 2007 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.