Narrative:

I was executing a power back from the gate in iah on feb/xx/95 at approximately XA19Z. Aircraft was a dc-9-30 and it weighed approximately 99.3 K. WX clear. Ramp dry I pwred back at approximately 1.2 EPR. During the pwrback I felt we were going back further than normal also that we were gaining momentum. The first officer had gone heads down to change radio frequency. We had been given a turn and the aircraft was pwring back southward perpendicular to taxiway 5X. I felt apprehensive about our proximity to the edge of the taxiway. I added forward thrust to stop our backward movement. Prior to the marshaller giving the come ahead signal. The engines appeared to spool slowly and I added more forward thrust activating the takeoff warning horn as we continued to move rearward. We felt a small bump as the aircraft slowed to a stop and then another small bump as the aircraft moved forward. I taxied ahead several more ft, parked the aircraft and set the parking brake. Operations was called and a maintenance supervisor and safety supervisor responded to the aircraft. The maintenance supervisor inspected the aircraft and said we had left the taxiway about 1 1/2 ft, but that it was straight in and straight out and that no side loads were incurred.' he told us the aircraft was 'ok for flight.' (notified us via headset). During the incident, the marshaller did not appear to realize how close we were to the edge of the taxiway or that the main gear had gone beyond the threshold of the taxiway.

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Original NASA ASRS Text

Title: PWRBACK -- TOO FAR.

Narrative: I WAS EXECUTING A PWR BACK FROM THE GATE IN IAH ON FEB/XX/95 AT APPROX XA19Z. ACFT WAS A DC-9-30 AND IT WEIGHED APPROX 99.3 K. WX CLR. RAMP DRY I PWRED BACK AT APPROX 1.2 EPR. DURING THE PWRBACK I FELT WE WERE GOING BACK FURTHER THAN NORMAL ALSO THAT WE WERE GAINING MOMENTUM. THE FO HAD GONE HEADS DOWN TO CHANGE RADIO FREQ. WE HAD BEEN GIVEN A TURN AND THE ACFT WAS PWRING BACK SOUTHWARD PERPENDICULAR TO TXWY 5X. I FELT APPREHENSIVE ABOUT OUR PROX TO THE EDGE OF THE TXWY. I ADDED FORWARD THRUST TO STOP OUR BACKWARD MOVEMENT. PRIOR TO THE MARSHALLER GIVING THE COME AHEAD SIGNAL. THE ENGS APPEARED TO SPOOL SLOWLY AND I ADDED MORE FORWARD THRUST ACTIVATING THE TKOF WARNING HORN AS WE CONTINUED TO MOVE REARWARD. WE FELT A SMALL BUMP AS THE ACFT SLOWED TO A STOP AND THEN ANOTHER SMALL BUMP AS THE ACFT MOVED FORWARD. I TAXIED AHEAD SEVERAL MORE FT, PARKED THE ACFT AND SET THE PARKING BRAKE. OPS WAS CALLED AND A MAINT SUPVR AND SAFETY SUPVR RESPONDED TO THE ACFT. THE MAINT SUPVR INSPECTED THE ACFT AND SAID WE HAD LEFT THE TXWY ABOUT 1 1/2 FT, BUT THAT IT WAS STRAIGHT IN AND STRAIGHT OUT AND THAT NO SIDE LOADS WERE INCURRED.' HE TOLD US THE ACFT WAS 'OK FOR FLT.' (NOTIFIED US VIA HEADSET). DURING THE INCIDENT, THE MARSHALLER DID NOT APPEAR TO REALIZE HOW CLOSE WE WERE TO THE EDGE OF THE TXWY OR THAT THE MAIN GEAR HAD GONE BEYOND THE THRESHOLD OF THE TXWY.

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.