Narrative:

After landing at stl, we were taxiing into gate a. Everything was uneventful until after being lined up on the lead-in line. At that time I noticed that the aircraft at gate B was beginning its push back. No conflict existed at that time and I surveyed gate a's safety zone (from right to left). The safety zone was completely clear. I then began to survey the area from left to right and as I leaned up in my seat and turned to the right to look at the wing tip area, I saw a conflict with the other wing-tip, and simultaneously to my starting to call for stop, the wing tips collided and the captain stopped immediately. As far as I know, the aircraft was still pushing back. As I turned back toward the front of the aircraft, I saw the marshaller giving the sign for hold. I informed the captain the wing tips had collided. After that, I assisted the captain in getting the aircraft towed to the gate and the passenger on their way. The reason this problem probably occurred was because these 2 safety zones had been re-aligned with crossing safety zones. This change was not known by myself or the captain. Prior knowledge probably would have keyed us to an impending conflict on taxiing in and definitely when the other aircraft began to push back.

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Original NASA ASRS Text

Title: MLG TAXIING TO GATE WITH MARSHALLER HAS WING TIP OF ACFT ON PUSHBACK AT NEXT GATE.

Narrative: AFTER LNDG AT STL, WE WERE TAXIING INTO GATE A. EVERYTHING WAS UNEVENTFUL UNTIL AFTER BEING LINED UP ON THE LEAD-IN LINE. AT THAT TIME I NOTICED THAT THE ACFT AT GATE B WAS BEGINNING ITS PUSH BACK. NO CONFLICT EXISTED AT THAT TIME AND I SURVEYED GATE A'S SAFETY ZONE (FROM R TO L). THE SAFETY ZONE WAS COMPLETELY CLR. I THEN BEGAN TO SURVEY THE AREA FROM L TO R AND AS I LEANED UP IN MY SEAT AND TURNED TO THE R TO LOOK AT THE WING TIP AREA, I SAW A CONFLICT WITH THE OTHER WING-TIP, AND SIMULTANEOUSLY TO MY STARTING TO CALL FOR STOP, THE WING TIPS COLLIDED AND THE CAPT STOPPED IMMEDIATELY. AS FAR AS I KNOW, THE ACFT WAS STILL PUSHING BACK. AS I TURNED BACK TOWARD THE FRONT OF THE ACFT, I SAW THE MARSHALLER GIVING THE SIGN FOR HOLD. I INFORMED THE CAPT THE WING TIPS HAD COLLIDED. AFTER THAT, I ASSISTED THE CAPT IN GETTING THE ACFT TOWED TO THE GATE AND THE PAX ON THEIR WAY. THE REASON THIS PROB PROBABLY OCCURRED WAS BECAUSE THESE 2 SAFETY ZONES HAD BEEN RE-ALIGNED WITH XING SAFETY ZONES. THIS CHANGE WAS NOT KNOWN BY MYSELF OR THE CAPT. PRIOR KNOWLEDGE PROBABLY WOULD HAVE KEYED US TO AN IMPENDING CONFLICT ON TAXIING IN AND DEFINITELY WHEN THE OTHER ACFT BEGAN TO PUSH BACK.

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.