Narrative:

While parking the aircraft under the guidance of the parking system; not one but two vehicles transgressed the operational safety zone. The parking system was fully operational and indicating the aircraft position properly. The proper aircraft type and flight number were displayed. The distance thermometer was green and no obstacles were observed as I proceeded into the safety zone. After crossing the beginning of the lead-in line; a truck drove through the safety zone in front of the aircraft between the aircraft and the parking display. It was not until the vehicle had passed clear of the safety zone that the parking system displayed 'stop'. After the vehicle had cleared safety zone; the 'stop' signal was removed from view and the normal displays were once again visible. I proceeded with parking the aircraft. Immediately upon aircraft movement; another vehicle; a small baggage cart tug; crossed the safety zone between aircraft and the display unit. Once again; the display unit did not show a 'stop' signal until after the vehicle had cleared the safety zone. The parking system's slow response makes this system impractical and unsafe. The response to a moving obstacle in the safe zone; should be immediate as to avoid and extremely unsafe situation. The slow response of the parking system could easily lead to an accident with possible injury to personnel and certain aircraft damage.

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Original NASA ASRS Text

Title: The A319 Captain reported that the parking system is slow to respond conflicting ground traffic in the Safety Zone.

Narrative: While parking the aircraft under the guidance of the parking system; not one but two vehicles transgressed the operational safety zone. The parking system was fully operational and indicating the aircraft position properly. The proper aircraft type and flight number were displayed. The distance thermometer was green and no obstacles were observed as I proceeded into the safety zone. After crossing the beginning of the lead-in line; a truck drove through the safety zone in front of the aircraft between the aircraft and the parking display. It was not until the vehicle had passed clear of the safety zone that the parking system displayed 'STOP'. After the vehicle had cleared safety zone; the 'STOP' signal was removed from view and the normal displays were once again visible. I proceeded with parking the aircraft. Immediately upon aircraft movement; another vehicle; a small baggage cart tug; crossed the safety zone between aircraft and the display unit. Once again; the display unit did not show a 'STOP' signal until after the vehicle had cleared the safety zone. The parking system's slow response makes this system impractical and unsafe. The response to a moving obstacle in the safe zone; should be immediate as to avoid and extremely unsafe situation. The slow response of the parking system could easily lead to an accident with possible injury to personnel and certain aircraft damage.

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.