Narrative:

Mdw ground cleared air carrier X to push back from gate xa to spot 2. At the same time an air carrier Y was cleared to push from a gate across the 'alleyway.' the aircraft were pushed into each other by the push back crews. Air carrier X also uses gate xb. I think ground control assumed air carrier X was pushing from xb even though the first officer told them xa and our anti-collision light was on. It was also below zero, which may have caused the wingwalkers to be less alert.

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Original NASA ASRS Text

Title: 2 ACR GND CREWS PUSHED THEIR RESPECTIVE AIRPLANES BACK INTO EACH OTHER. THE GND CTL HAD AUTH BOTH PUSHBACKS. THE WX TEMP WAS BELOW FREEZING AND IT WAS STILL DARK.

Narrative: MDW GND CLRED ACR X TO PUSH BACK FROM GATE XA TO SPOT 2. AT THE SAME TIME AN ACR Y WAS CLRED TO PUSH FROM A GATE ACROSS THE 'ALLEYWAY.' THE ACFT WERE PUSHED INTO EACH OTHER BY THE PUSH BACK CREWS. ACR X ALSO USES GATE XB. I THINK GND CTL ASSUMED ACR X WAS PUSHING FROM XB EVEN THOUGH THE FO TOLD THEM XA AND OUR ANTI-COLLISION LIGHT WAS ON. IT WAS ALSO BELOW ZERO, WHICH MAY HAVE CAUSED THE WINGWALKERS TO BE LESS ALERT.

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.