Narrative:

We had an inoperative APU. The decision was made to start both engines at gate. Communication with ground personnel was established. All before start checklists were completed. During pushback checklist, it was discovered a door light was illuminated. It took several attempts to get light to extinguish. The start sequence was begun with the captain manipulating the fuel levers. After the #2 engine was started, I began my after start flow. At a point on the overhead panel, I sensed forward movement and exclaimed 'brakes, brakes.' the aircraft moved forward approximately 5 ft displacing the tug slightly to the left of the aircraft's centerline. An assessment was made to ensure everyone's safety. Maintenance came to the aircraft to inspect the nosewheel assembly. It was discovered the tow bar shear pin had broken. No other damage was discovered. Mins later, we commenced pushback and continued on our flight. I believe our situation was caused by a breakdown in communication and normal procedures. The aircraft was not chocked for the start. A 'brakes set' call was never made to the captain prior to engine start. I believe a safer method of starting engines is to have the co-pilot make all starts (tops and bottoms) so the captain's attention can be outside the aircraft. He would have noticed the forward movement earlier. I believe there should be an APU inoperative dispatch written procedure in all aircraft pom's for the crew to review prior to conducting this abnormal event. It should emphasize 'brakes set.' we were lucky no one was hurt, and learned a valuable lesson.

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Original NASA ASRS Text

Title: MD88 CREW ROLLED INTO THE PUSHBACK TUG AFTER THE CAPT DID NOT SET THE BRAKES. THE CREW STARTED BOTH ENGS ON PUSHBACK BECAUSE THE APU WAS MEL'ED INOP.

Narrative: WE HAD AN INOP APU. THE DECISION WAS MADE TO START BOTH ENGS AT GATE. COM WITH GND PERSONNEL WAS ESTABLISHED. ALL BEFORE START CHKLISTS WERE COMPLETED. DURING PUSHBACK CHKLIST, IT WAS DISCOVERED A DOOR LIGHT WAS ILLUMINATED. IT TOOK SEVERAL ATTEMPTS TO GET LIGHT TO EXTINGUISH. THE START SEQUENCE WAS BEGUN WITH THE CAPT MANIPULATING THE FUEL LEVERS. AFTER THE #2 ENG WAS STARTED, I BEGAN MY AFTER START FLOW. AT A POINT ON THE OVERHEAD PANEL, I SENSED FORWARD MOVEMENT AND EXCLAIMED 'BRAKES, BRAKES.' THE ACFT MOVED FORWARD APPROX 5 FT DISPLACING THE TUG SLIGHTLY TO THE L OF THE ACFT'S CTRLINE. AN ASSESSMENT WAS MADE TO ENSURE EVERYONE'S SAFETY. MAINT CAME TO THE ACFT TO INSPECT THE NOSEWHEEL ASSEMBLY. IT WAS DISCOVERED THE TOW BAR SHEAR PIN HAD BROKEN. NO OTHER DAMAGE WAS DISCOVERED. MINS LATER, WE COMMENCED PUSHBACK AND CONTINUED ON OUR FLT. I BELIEVE OUR SIT WAS CAUSED BY A BREAKDOWN IN COM AND NORMAL PROCS. THE ACFT WAS NOT CHOCKED FOR THE START. A 'BRAKES SET' CALL WAS NEVER MADE TO THE CAPT PRIOR TO ENG START. I BELIEVE A SAFER METHOD OF STARTING ENGS IS TO HAVE THE CO-PLT MAKE ALL STARTS (TOPS AND BOTTOMS) SO THE CAPT'S ATTN CAN BE OUTSIDE THE ACFT. HE WOULD HAVE NOTICED THE FORWARD MOVEMENT EARLIER. I BELIEVE THERE SHOULD BE AN APU INOP DISPATCH WRITTEN PROC IN ALL ACFT POM'S FOR THE CREW TO REVIEW PRIOR TO CONDUCTING THIS ABNORMAL EVENT. IT SHOULD EMPHASIZE 'BRAKES SET.' WE WERE LUCKY NO ONE WAS HURT, AND LEARNED A VALUABLE LESSON.

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.