Narrative:

During pushback; I noticed the wing walker sprinting back towards the aircraft with his wands set in an 'X' orientation indicating that we should stop. I looked back at the tug driver and tried communicating but noticed something wasn't right. The aircraft was still moving backwards; but the tug had stopped. I realized that the tow bar had become disconnected and began to make efforts to stop the airplane gently. I tried slowly applying the toe brakes and parking brake together. Thankfully the pushback was occurring towards an upslope so the plane quickly slowed on its own and we avoided having it tilt back on the tail or damaging the nose. With the aircraft stopped; the ground crew checked the nose gear and determined nothing was damaged so we continued with the flight. The ground crew noticed first; then I saw the tug slowly separating from the airplane.the ground crew admitted to not installing a safety pin on the tow bar; therefore allowing the plane to come unattached. [Suggest] better training for ground crew on installing the tow bar.

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Original NASA ASRS Text

Title: Dash 8 Captain reported his aircraft lost contact with the tow bar during push back when the ground crew failed to use the safety pin.

Narrative: During pushback; I noticed the wing walker sprinting back towards the aircraft with his wands set in an 'X' orientation indicating that we should stop. I looked back at the tug driver and tried communicating but noticed something wasn't right. The aircraft was still moving backwards; but the tug had stopped. I realized that the tow bar had become disconnected and began to make efforts to stop the airplane gently. I tried slowly applying the toe brakes and parking brake together. Thankfully the pushback was occurring towards an upslope so the plane quickly slowed on its own and we avoided having it tilt back on the tail or damaging the nose. With the aircraft stopped; the ground crew checked the nose gear and determined nothing was damaged so we continued with the flight. The ground crew noticed first; then I saw the tug slowly separating from the airplane.The ground crew admitted to not installing a safety pin on the tow bar; therefore allowing the plane to come unattached. [Suggest] Better training for ground crew on installing the tow bar.

Data retrieved from NASA's ASRS site 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.