Date: 201309
Local time of day: 1201-1800
Location: DTW.Airport, MI
Flight conditions: VMC
Light: Daylight
Aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground DTW
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Time Pressure; Communication Breakdown; Situational Awareness; Workload
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Vehicle
Detector: Person Gate Agent / CSR
When detected: Taxi
Result: Aircraft Aircraft Damaged
Contributing factors: Company Policy; Environment - Non Weather Related; Human Factors; Procedure
Primary problem: Ambiguous

Narrative: During pushback ship was pushed into a parked vehicle sustaining damage to the right under wing area proximate to the flap fairings. Pushback was halted; passengers deplaned under supervision of airport and station personnel. At scheduled departure time; flight was completely ready to depart in all respects except that catering was pending. Catering crew arrived at plane approximately at scheduled departure time. While the flight attendants and catering worked in the galley area; I was in communications with the pushback Tug Operator. Communications were normal. When the cabin servicing door was closed I released the brakes upon communication with and concurrence of the Tug Operator. Within approximately 1-2 minutes the Tug Operator 'pulled-up' [the aircraft] and he was standing by for the catering truck to clear the area. At this time I requested and received a push back clearance from DTW Ground Control. Upon receiving the clearance; I informed the Tug Operator that we had clearance to push. I stated you are cleared to push when ready; or words to that effect. The Tug Operator acknowledged and informed that the catering truck was still not clear. Moments later the Tug Driver informed me that the catering truck was clear; and he was signaling his wing walker on the left side of the plane. With the wing walker in place; the Tug Driver commenced pushback. Moments later I heard shouting; and the Tug Driver stopped the pushback abruptly. A small catering passenger vehicle was wedged underneath the right under wing area.Lack of a second wing walker. I was informed that at DTW station policy allows for aircraft movement with only 1 wing walker. This is not a good policy.   Improperly parked vehicle; does policy allow unnecessary service vehicles to park in close proximity to aircraft?


Second narrative: At 5 minutes prior to scheduled pushback; I called Operations; for the third time; requesting catering. Catering arrived at the aircraft at about our scheduled push time. Everyone was on board and we all just waited for them to finish. When catering closed the service door; the Captain told the Tug Operator he was releasing brakes and to let him know when the catering truck was clear so he could call for pushback.Our push was delayed by catering and the ground crew may have felt rushed to get the aircraft out. The catering truck was blocking the view of the car behind. The Tug Operator did say that he had seen the car previously; but forgot it was there by the time we pushed. We only had one wing walker on the left hand side of the aircraft. The Captain and I followed company procedures and could not have done anything to help prevent this event.I don't think there is anything I could have done. I was already on board when catering arrived and could not see the car from the flight deck. A second wing walker on the right side would have prevented this accident.


Synopsis: An air carrier aircraft was pushed back into a catering passenger type vehicle because both the flight and ground crews were rushed after a late catering and the solo wing walker did not see the vehicle.