Narrative:

During pushback, the ground crew had not installed the nosewheel steering bypass pin, and I did not catch this. As hydraulic pressure came up during engine start, the tow bar was twisted. The tow bar shear pins did not break. The nose landing gear tow bar attachment was broken from the airplane. Both nose tires were damaged in the breaking of the nose landing gear tow bar attachment. No personnel were injured. The tow bar was found to have the incorrect shear pins installed. This second and final leg of a 2-DAY trip was a fairly early east coast departure time of XF00. The crew had to get up at XA45 domicile time after a night where neither cockpit crew member had slept very well.

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Original NASA ASRS Text

Title: AN A320 GND PERSONNEL FAILED TO INSTALL THE NOSEWHEEL GEAR PIN BEFORE THE ACFT WAS PUSHED BACK. WHEN THE ENG WAS STARTED, THE HYD PRESSURE BUILT UP AND BROKE THE TOW BAR ATTACHMENT AND DAMAGED THE NOSE TIRES.

Narrative: DURING PUSHBACK, THE GND CREW HAD NOT INSTALLED THE NOSEWHEEL STEERING BYPASS PIN, AND I DID NOT CATCH THIS. AS HYD PRESSURE CAME UP DURING ENG START, THE TOW BAR WAS TWISTED. THE TOW BAR SHEAR PINS DID NOT BREAK. THE NOSE LNDG GEAR TOW BAR ATTACHMENT WAS BROKEN FROM THE AIRPLANE. BOTH NOSE TIRES WERE DAMAGED IN THE BREAKING OF THE NOSE LNDG GEAR TOW BAR ATTACHMENT. NO PERSONNEL WERE INJURED. THE TOW BAR WAS FOUND TO HAVE THE INCORRECT SHEAR PINS INSTALLED. THIS SECOND AND FINAL LEG OF A 2-DAY TRIP WAS A FAIRLY EARLY EAST COAST DEP TIME OF XF00. THE CREW HAD TO GET UP AT XA45 DOMICILE TIME AFTER A NIGHT WHERE NEITHER COCKPIT CREW MEMBER HAD SLEPT VERY WELL.

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.