Narrative:

Due to tow-bar disconnection issues experienced during aircraft pushback from gates at multiple airports around the network; we would like clarification on the standard procedures that we should expect. Of particular concern is the position of the tow-bar relative to the aircraft's longitudinal axis after push back; especially when the disconnect procedure occurs with the tow-bar oriented at nearly right angles to the axis; with the nose wheel at the same angle.earlier this summer; I experienced a tow-bar shear pin failure during the disconnect procedure after the aircraft was stopped and the aircraft brakes were set. After the shear pin failed; releasing the tow-bar from the nose gear; the pushback crew showed us the tow safety pin and left. I requested maintenance to inspect the nose gear prior to taxi. No damage was found; and the mechanics retrieved the broken pieces of the shear pin from the tarmac under the nose of the aircraft after the pushback crew departed.1. Would the ground crew's performance in this case be considered normal procedure for a pushback that experiences a shear-pin failure during tow-bar disconnection?[another time] I was pushed back from the gate; tailing east. Clearance was given to start both engines and we did so. The pushback crew stopped the aircraft aligned on the taxi line; but with the nose gear and tow-bar at a severe angle to the aircraft longitudinal axis. They could not get the tow-bar disconnected and asked me to release the brakes to push back further in order to straighten the tow-bar so as to align with the aircraft; thereby relieving the lateral torque. I released the brake and the crew began to move the aircraft. Almost immediately the tow-bar became disconnected from the aircraft nose gear; and with both engines running; the high idle thrust launched the aircraft forward toward the pushback tractor and ramp crew under the nose of the aircraft. I immediately set the parking brake and full braking pressure was applied abruptly stopping the aircraft before crushing the ground crew between aircraft nose and the pushback tractor; also avoiding a collision with the push back tractor. They showed us the tow safety pin and left. I did not suspect any damage to the nose gear. We departed where a walk around inspection also revealed no damage.2. Does the ground service manual address alignment of the tow-bar prior to stopping the pushback and before setting the aircraft brake?3. Is there an approved ground service training manual?4. If a training manual does exist; how does it train to position the tow-bar relative to the aircraft prior to disconnect?one of our ramp agents [was hurt] after being run over by the aircraft nose wheels during gate arrival. I recently had to bring the aircraft to a stop because a ramp agent was squatting down next to the chalks ready for the nose gear while I was following the marshaller's guidance onto the gate. I motioned for him to clear the area before I continued to the stopping point because I could no longer see him under the aircraft while moving forward.my concern is that too many of the ramp employees around the network do not have the knowledge base and experience necessary to safely perform their assigned duties.in addition; their performance on the job is not being supervised properly and that we may suffer another severe injury or worse.suggestion: [we] adopt and train a procedure where the tow-bar will be aligned with the longitudinal axis of the aircraft prior to setting the brakes after push back and before disconnecting.

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Original NASA ASRS Text

Title: A320 Captain reported a tow bar disconnect during pushback due to shear-pin failure as the push crew aligned the nose wheel. Captain questioned ground personnel training may have contributed to the event.

Narrative: Due to tow-bar disconnection issues experienced during aircraft pushback from gates at multiple airports around the network; we would like clarification on the standard procedures that we should expect. Of particular concern is the position of the tow-bar relative to the aircraft's longitudinal axis after push back; especially when the disconnect procedure occurs with the tow-bar oriented at nearly right angles to the axis; with the nose wheel at the same angle.Earlier this summer; I experienced a tow-bar shear pin failure during the disconnect procedure after the aircraft was stopped and the aircraft brakes were set. After the shear pin failed; releasing the tow-bar from the nose gear; the pushback crew showed us the tow safety pin and left. I requested Maintenance to inspect the nose gear prior to taxi. No damage was found; and the mechanics retrieved the broken pieces of the shear pin from the tarmac under the nose of the aircraft after the pushback crew departed.1. Would the ground crew's performance in this case be considered normal procedure for a pushback that experiences a shear-pin failure during tow-bar disconnection?[Another time] I was pushed back from the gate; tailing east. Clearance was given to start both engines and we did so. The pushback crew stopped the aircraft aligned on the taxi line; but with the nose gear and tow-bar at a severe angle to the aircraft longitudinal axis. They could not get the tow-bar disconnected and asked me to release the brakes to push back further in order to straighten the tow-bar so as to align with the aircraft; thereby relieving the lateral torque. I released the brake and the crew began to move the aircraft. Almost immediately the tow-bar became disconnected from the aircraft nose gear; and with both engines running; the high idle thrust launched the aircraft forward toward the pushback tractor and ramp crew under the nose of the aircraft. I immediately set the parking brake and full braking pressure was applied abruptly stopping the aircraft before crushing the ground crew between aircraft nose and the pushback tractor; also avoiding a collision with the push back tractor. They showed us the tow safety pin and left. I did not suspect any damage to the nose gear. We departed where a walk around inspection also revealed no damage.2. Does the ground service manual address alignment of the tow-bar prior to stopping the pushback and before setting the aircraft brake?3. Is there an approved ground service training manual?4. If a training manual does exist; how does it train to position the tow-bar relative to the aircraft prior to disconnect?One of our ramp agents [was hurt] after being run over by the aircraft nose wheels during gate arrival. I recently had to bring the aircraft to a stop because a ramp agent was squatting down next to the chalks ready for the nose gear while I was following the marshaller's guidance onto the gate. I motioned for him to clear the area before I continued to the stopping point because I could no longer see him under the aircraft while moving forward.My concern is that too many of the ramp employees around the network do not have the knowledge base and experience necessary to safely perform their assigned duties.In addition; their performance on the job is not being supervised properly and that we may suffer another severe injury or worse.Suggestion: [We] adopt and train a procedure where the tow-bar will be aligned with the longitudinal axis of the aircraft prior to setting the brakes after push back and before disconnecting.

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.