Narrative:

During pushback from gate at sna just as the aircraft was reversing a loud clunk was heard and the aircraft began to drift ahead of the tug. I gently applied brakes as the tug driver called out that the tow bar had broken. #2 engine was running and #1 engine was turning to start. Another aircraft was moving up to take the gate we vacated and our airplane was far enough into the taxiway to allow taxi for takeoff. I assumed we had a clean break from the tow bar and instructed the tug operator to disconnect and I would take the aircraft from there. We informed ground of our intentions since they were expecting the tug to pull the aircraft forward for the airplane to take our gate. The tug operator concurred and we proceeded to conduct a normal taxi and takeoff. About 30 mins prior to etp we were informed by dispatch that a piece of metal and skid marks had been found in our pushback area and that one or more of our wheels may be damaged. Seeing no reason to return to sna the flight was continued. Because of the lack of vibration on takeoff; I assumed worse case would be one or both nose tires would deflate in the air. Did not declare an emergency but asked for a crash truck to meet us at the midfield turnoff to advise us of any tires were shredding. Informed the passenger during descent and emphasized that we anticipated no problem on landing. A normal landing by the first officer and taxi by me to the gate at koa. Probably should have insisted on inspection by a mechanic but the break sounded very 'clean.'

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Original NASA ASRS Text

Title: B737 ON PUSHBACK HAS THE TOW BAR BREAK AND IS NOTIFIED INFLT BY DISPATCH OF METAL FOUND IN THEIR PUSHBACK AREA.

Narrative: DURING PUSHBACK FROM GATE AT SNA JUST AS THE ACFT WAS REVERSING A LOUD CLUNK WAS HEARD AND THE ACFT BEGAN TO DRIFT AHEAD OF THE TUG. I GENTLY APPLIED BRAKES AS THE TUG DRIVER CALLED OUT THAT THE TOW BAR HAD BROKEN. #2 ENG WAS RUNNING AND #1 ENG WAS TURNING TO START. ANOTHER ACFT WAS MOVING UP TO TAKE THE GATE WE VACATED AND OUR AIRPLANE WAS FAR ENOUGH INTO THE TXWY TO ALLOW TAXI FOR TKOF. I ASSUMED WE HAD A CLEAN BREAK FROM THE TOW BAR AND INSTRUCTED THE TUG OPERATOR TO DISCONNECT AND I WOULD TAKE THE ACFT FROM THERE. WE INFORMED GND OF OUR INTENTIONS SINCE THEY WERE EXPECTING THE TUG TO PULL THE ACFT FORWARD FOR THE AIRPLANE TO TAKE OUR GATE. THE TUG OPERATOR CONCURRED AND WE PROCEEDED TO CONDUCT A NORMAL TAXI AND TKOF. ABOUT 30 MINS PRIOR TO ETP WE WERE INFORMED BY DISPATCH THAT A PIECE OF METAL AND SKID MARKS HAD BEEN FOUND IN OUR PUSHBACK AREA AND THAT ONE OR MORE OF OUR WHEELS MAY BE DAMAGED. SEEING NO REASON TO RETURN TO SNA THE FLT WAS CONTINUED. BECAUSE OF THE LACK OF VIBRATION ON TKOF; I ASSUMED WORSE CASE WOULD BE ONE OR BOTH NOSE TIRES WOULD DEFLATE IN THE AIR. DID NOT DECLARE AN EMER BUT ASKED FOR A CRASH TRUCK TO MEET US AT THE MIDFIELD TURNOFF TO ADVISE US OF ANY TIRES WERE SHREDDING. INFORMED THE PAX DURING DSCNT AND EMPHASIZED THAT WE ANTICIPATED NO PROB ON LNDG. A NORMAL LNDG BY THE FO AND TAXI BY ME TO THE GATE AT KOA. PROBABLY SHOULD HAVE INSISTED ON INSPECTION BY A MECH BUT THE BREAK SOUNDED VERY 'CLEAN.'

Data retrieved from NASA's ASRS site as of January 2009 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.