Air carrier flight crew reported after push back from the gate and during starting of the first engine the aircraft rolled into the tug. The aircraft and tug were damaged in the event. The Captain believes its possible the parking brake was accidentally released or perhaps never set. The First Officer suggested the after start flow should be changed.
Synopsis
Air carrier flight crew reported after push back from the gate and during starting of the first engine the aircraft rolled into the tug. The aircraft and tug were damaged in the event. The Captain believes its possible the parking brake was accidentally released or perhaps never set. The First Officer suggested the after start flow should be changed.
Narrative
Aircraft moved while Ground Crew was still at nose of aircraft. Aircraft made contact with tug and glass window broke on driver. Driver screamed set parking brake; and again screamed set parking brake. I looked down at parking brake and it was off so I reached down to set it immediately. Then Ground Staff asked us to shut down engines. Ground staff was quite shaken up and got out of the tug. Eventually tug was removed and aircraft was tugged back to gate.Ground Crew was yelling to set parking brake and I noticed we were moving as well.I remember when Ground Staff asked Captain to set parking brake; I saw the Captain look out the window and make sure we were not moving; and his arm went out and down to set parking brake; yet I did not see him actually set the parking brake. After engine 2 started we both started our flow. I started with speed brake armed; and went to FMS for CG percentage to set. I went and set the trim to around 28%; which was UP0.8; and put it into the FMS. That is about the time Ground Staff was screaming at us to set the parking brake. I looked at Captain and looked down at the parking brake and it was off; so I immediately set the parking brake for the Captain and we came to a sudden stop. I didn't even notice we were moving until we were told to set parking brake. And I don't know if Captain set the parking brake or not before and then released it somehow. I looked up at Captain since I thought parking brake was set; so I looked down at the parking brake and it was off; so I reached down to set the brake to on.First Officer I'm not sure of what exactly happened if the Captain set the parking brake the first time they asked him to; but I know it was off later. I flew this type aircraft before for 7 years; and the after start flow at this Company is slightly different. I was told here to tell the Ground Staff to disconnect first before starting the PF (Pilot Flying) flow with the start/ignition switch. (My old Company it was after the PF set the start/ignition selector to normal; then tell Ground Crew disconnect and next start PF flow). However it's quite possible that the Captain after telling Ground Crew; when he went to move the start/ignition back to normal he inadvertently took off the parking brake as well. I personally like to set the start/ignition switch back to normal first before discounting. The parking brake and start/ignition switch are relatively close and have a same rotation of right and left. Other suggestion; is to always double verify before we move switches. Two step actions is hand to the switch; look at the switch to verify; then move the switch after verified.
Second reporter narrative
Our aircraft impacted the ground service equipment during engine start.Everything was normal during pushback. Reaching our final position; I was directed by the Ground Crew to set the parking brake; which I did referencing outside for relative motion; and using the ECAM as an indication of the parking brake being set. The parking brake handle was moved to 'on' and the accumulator pressure was checked normal. We were stationary for at least 1.5-2 minutes; while the subsequent engine stabilised to 'avail.' Once seeing that the #1 engine was stable; I simultaneously directed the Ground Crew 'clear to disconnect;' while I started my after start flow. The flow included the ignition switch to normal; engine cooling pushbutton off; crossbleed valve to auto; APU bleed pushbutton off; and APU master off.Almost immediately after securing the APU; I heard the Ground Crew screaming for 'Brakes; Brakes.' I pushed down on the brake pedals with my feet while the FO (First Officer) looked down at the pedestal and saw the parking brake off. He reached down and selected the parking brake on.The Ground Crew asked that we secure our engines. I directed the FO (First Officer) to select the APU back on (it had not completed it's shutdown); and I selected both engine master switches to off.I then asked the Ground Personnel if she was OK. She responded that she was OK; but that the tug was wedged under the nose of the airplane and she had concerns about backing it out of its current position. Shortly thereafter the headset was disconnected (or at least there was no response on the intercom).I could see the female tug driver was removed from the tug and taken to a golf cart that was nearby; visibly shaken.We were without any communication from the ground for more than 15 minutes (estimated); meanwhile emergency equipment and Ground Service Personnel surrounded the airplane in response to the incident. I made two PAs to the passengers explaining that we had an issue with the ground service equipment and that the condition of the airplane needed to be assessed before we could continue.Eventually; the original tug was removed from under the airplane; a second tug was connected to the plane and we were towed into a gate where the passengers were disembarked. At this point I was able to visibly inspect the aircraft and found the TAT probe broken and skin damage to the underside of the left forward section of the nose cone. I saw no damage to the nose landing gear.Error was brought to our attention by the ground personnel via intercom.I believe I unnecessarily rushed through my after start flow potentially making an error. I do not recall manipulating the parking brake during this time; but it is the most likely explanation. Additionally; with my attention on the overhead panel and the Pilot Monitoring concentrating on his responsibilities; neither of us were aware of the aircraft movement until the tug driver called for brakes.Captains Response:Both myself and the First Officer reacted to the intercom immediately. I responded by using the manual brakes and the First Officer saw the position of the parking brake handle and corrected it.Ultimately; I believe it was my human error that caused the incident. I don't recall making the error; but it is the most likely explanation for the sequence of events. Adding to my error was the lack of situational awareness while manipulating switches during the after start flow. Both pilots were unaware of aircraft movement despite being a clear; daytime event. Night time or reduced visibility would have amplified this lack of SA (Situational Awareness). Perhaps; if the after start flow was initiated after all personnel are clear of the aircraft it could have prevented this from happening.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.