Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 160
Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Vehicle
Aircraft Aircraft Damaged; General Maintenance Action
Human Factors
An incident occurred during pushback; resulting in the towbar damaging a fitting on the bottom of the nose gear strut. The fitting is used to service the strut with hydraulic fluid and compressed nitrogen gas. As a result; the strut lost both fluid and nitrogen gas which caused the strut to compress. Maintenance was required to replace the fitting and service the strut.The initial pushback proceeded normally. After a short pushback; I was told to set the brakes. I didn't set the brakes and I told the Pushback Crew to push us back farther. The Crew told me that this is where they stop the pushback. I told the Crew we needed to be pushed back farther back. The Pushback Crew said something about pushing back any farther and we would be on a taxiway. We were in a non-movement area; but we called Ground Control and were told push wherever we needed to. I told the Pushback Crew that we were fine and to push us back farther. We were pushed back and came to a stop. I asked about setting the brakes. We stopped briefly and then the aircraft started moving forward. No communication had come from the Pushback Crew regarding pushback complete or set the brakes. I stopped the aircraft with the aircraft's brakes and asked the Pushback Crew what was going on. They told me the towbar had disconnected from the nose gear; hit the nose gear when the aircraft rolled forward; and now fluid was coming from the nose gear. I told them we would be returning to the gate. We called DAL Ops and told them we were returning to the gate. We returned to Gate where Maintenance repaired and serviced the nose gear strut.I have had the towbar disconnect on one other occasion during pushback. It occurred at the same time as this incident; just as the tug was bringing the aircraft to a stop. The aircraft came to a brief stop; the towbar disconnected; and the aircraft started rolling forward. That Pushback Crew told me the handle on the towbar that locks the towbar to the nose gear did not have the safety pin properly installed. The result was the handle floated up and released the towbar from the nose gear. I am very thankful that our Pushback Crew was not injured during this incident.
[Report narrative contained no additional information.]
Air Carrier flight crew reported the nose gear was damaged when it was struck by the pushback tug.