An A320 flight crew failed to insure the parking brake was set prior to clearing the ground crew to disconnect the tow bar. A weak interphone system and the flight crew's preoccupation with briefing special takeoff procedures during the pushback contributed.
Synopsis
An A320 flight crew failed to insure the parking brake was set prior to clearing the ground crew to disconnect the tow bar. A weak interphone system and the flight crew's preoccupation with briefing special takeoff procedures during the pushback contributed.
Narrative
When ground person hooked up to the interphone; it was very weak and I had to ask several times during push back process to 'say again'. Push back was normal until after the clear to start engines clearance was given. The First Officer and I were discussing T-procedure and terrain issues; during which time I heard the tug driver talk. Thinking (incorrectly) it was at the point during push back that the response was to 'disconnect headset' I said that to the tug driver. When I saw tug driver back away from airplane I noticed the plane start to roll forward. The plane rolled several inches to about 1 FT as near as I could tell when I immediately applied brakes and stopped the airplane. At that point the normal 'salute and release from guidance' procedure was accomplished and we taxied out. Thank God no one was injured and no equipment was damaged. Fatigue was a factor due to previous long duty days on this ID. I think the low volume during the push back was also a factor; otherwise it would have more obvious what point in the push back that we were in.
Second reporter narrative
During push back the Captain and I were clarifying some T Procedure elements. In the future I; as a First Officer; will be certain that there is no distraction through conversation until we have received a release from guidance.
More incidents for this aircraft family →
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.