Narrative:

Operating an MD80 from lga-houston (iah). Aircraft had an inoperative APU. Started #1 engine at gate using external electrical power and air. I requested the start of #2 engine before disconnecting external power/air. (Request denied.) after disconnecting the power and air, started pushback and was 'cleared to start #2 engine.' during the start, I noticed the tug passing aft of my left window. The tug was much closer to the aircraft than normal (ie, right beneath me). I applied brakes and shut both engines down and set the parking brake. The tug in fact made contact with fuselage, causing damage to aircraft and tug. There were no injuries. Note: the ramp was wet. One important factor, I believe, is the difficulty I had communicating with the tug operator on the headset from the beginning. At first I did not even realize he had spoken (prior to engine start) and suggested he had his microphone plug in the wrong jack. He determined that was not the case and would speak louder. After #1 engine start, he made a transmission but I had to ask for a repeat -- which he did. He acknowledged my call stating brakes were released and clearance to push back. That was the last I heard from him on the headset. My greatest attention was to monitor the #2 engine start, including the necessary air pressure. I believe the combination of engine power, wet ramp, angular displacement of the tug tow bar to the longitudinal axis of the airplane and lack of (or breakdown) communication between tug operator and me led to the tug's contact with, and subsequent damage to the airplane.

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Original NASA ASRS Text

Title: THE ACFT HAD AN INOP APU. THE CAPT'S REQUEST TO START BOTH ENGS AT THE GATE USING EXTERNAL AIR AND ELECTRIC WAS DENIED. AFTER COMPANY GND PERSONNEL DISCONNECTED THE EXTERNAL ELECTRICAL AND AIR THE PUSH BACK WAS COMMENCED AND TUG DRIVER SAID 'CLRED TO START #2 ENG.' DURING THE XBLEED START THE CAPT NOTICED THE TUG PASSING AFT BY HIS L WINDOW. HE APPLIED THE BRAKES AND SHUT DOWN BOTH ENGS AND SET THE PARKING BRAKE. THE RAMP WAS WET. THE TUG HAD COLLIDED WITH THE FUSELAGE.

Narrative: OPERATING AN MD80 FROM LGA-HOUSTON (IAH). ACFT HAD AN INOP APU. STARTED #1 ENG AT GATE USING EXTERNAL ELECTRICAL PWR AND AIR. I REQUESTED THE START OF #2 ENG BEFORE DISCONNECTING EXTERNAL PWR/AIR. (REQUEST DENIED.) AFTER DISCONNECTING THE PWR AND AIR, STARTED PUSHBACK AND WAS 'CLRED TO START #2 ENG.' DURING THE START, I NOTICED THE TUG PASSING AFT OF MY L WINDOW. THE TUG WAS MUCH CLOSER TO THE ACFT THAN NORMAL (IE, RIGHT BENEATH ME). I APPLIED BRAKES AND SHUT BOTH ENGS DOWN AND SET THE PARKING BRAKE. THE TUG IN FACT MADE CONTACT WITH FUSELAGE, CAUSING DAMAGE TO ACFT AND TUG. THERE WERE NO INJURIES. NOTE: THE RAMP WAS WET. ONE IMPORTANT FACTOR, I BELIEVE, IS THE DIFFICULTY I HAD COMMUNICATING WITH THE TUG OPERATOR ON THE HEADSET FROM THE BEGINNING. AT FIRST I DID NOT EVEN REALIZE HE HAD SPOKEN (PRIOR TO ENG START) AND SUGGESTED HE HAD HIS MIKE PLUG IN THE WRONG JACK. HE DETERMINED THAT WAS NOT THE CASE AND WOULD SPEAK LOUDER. AFTER #1 ENG START, HE MADE A XMISSION BUT I HAD TO ASK FOR A REPEAT -- WHICH HE DID. HE ACKNOWLEDGED MY CALL STATING BRAKES WERE RELEASED AND CLRNC TO PUSH BACK. THAT WAS THE LAST I HEARD FROM HIM ON THE HEADSET. MY GREATEST ATTN WAS TO MONITOR THE #2 ENG START, INCLUDING THE NECESSARY AIR PRESSURE. I BELIEVE THE COMBINATION OF ENG PWR, WET RAMP, ANGULAR DISPLACEMENT OF THE TUG TOW BAR TO THE LONGITUDINAL AXIS OF THE AIRPLANE AND LACK OF (OR BREAKDOWN) COM BTWN TUG OPERATOR AND ME LED TO THE TUG'S CONTACT WITH, AND SUBSEQUENT DAMAGE TO THE AIRPLANE.

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.