Narrative:

During pushback the tow bar became disconnected. Captain stopped the aircraft using the emergency/parking brake. The sudden stop resulted in both flight attendants sustaining injuries requiring evaluation at the hospital. Captain requested FAA jumpseater to check on the flight attendants and solicit medical help from the passengers as needed. He reported both flight attendants had lost consciousness and one was bleeding; and that on board medical professionals were tending to them. Captain instructed me to coordinate getting medics while he called dispatch. I requested emt/ambulance through ops and also requested airstairs be brought to the aircraft so the emts would have swift access to the aircraft. With passengers (those tending to the flight attendants) up; unknown status of tow bar assembly; and not wanting to further jar the flight attendants if further difficulties should arise on tow-in; we were hesitant to move the aircraft. It became apparent that ops was unable to timely provide airstairs. We were informed a new tow bar had been attached and inspected; and then were towed back to the gate. The captain and I disarmed the boarding door and the flight attendants were then taken to the hospital. The parking brake is rarely used to stop the aircraft; thus the finesse required to do it without lurch would be very difficult to achieve. If the number 1 hyd pump was on during pushback; partial normal brakes would be retained and the nose wheel steering would still be de-energized. Some carriers have procedures requiring the flight attendants to be seated until the pushback is complete. Unfortunately these events are not that uncommon; this is the second time in less than a year I've seen a tow bar fail on push back.

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Original NASA ASRS Text

Title: EMB190 flight crew experiences a break away during pushback requiring the use of the parking brake to stop the aircraft. The sudden stop causes both flight attendants to fall and be seriously injured.

Narrative: During pushback the tow bar became disconnected. Captain stopped the aircraft using the emergency/parking brake. The sudden stop resulted in both flight attendants sustaining injuries requiring evaluation at the hospital. Captain requested FAA jumpseater to check on the flight attendants and solicit medical help from the passengers as needed. He reported both flight attendants had lost consciousness and one was bleeding; and that on board medical professionals were tending to them. Captain instructed me to coordinate getting medics while he called Dispatch. I requested EMT/ambulance through Ops and also requested airstairs be brought to the aircraft so the EMTs would have swift access to the aircraft. With passengers (those tending to the flight attendants) up; unknown status of tow bar assembly; and not wanting to further jar the flight attendants if further difficulties should arise on tow-in; we were hesitant to move the aircraft. It became apparent that Ops was unable to timely provide airstairs. We were informed a new tow bar had been attached and inspected; and then were towed back to the gate. The Captain and I disarmed the boarding door and the flight attendants were then taken to the hospital. The parking brake is rarely used to stop the aircraft; thus the finesse required to do it without lurch would be very difficult to achieve. If the Number 1 Hyd Pump was on during pushback; partial normal brakes would be retained and the nose wheel steering would still be de-energized. Some carriers have procedures requiring the flight attendants to be seated until the pushback is complete. Unfortunately these events are not that uncommon; this is the second time in less than a year I've seen a tow bar fail on push back.

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.