Incident Details
On 2 September 2003 at 1230 UTC, a Boeing 737-73V, registration G-EZJN, was taxiing onto a stand at Edinburgh Airport, Scotland, using the AGNIS (Azimuth Guidance for Nose-In Stands) and PAPA (Parallax Aircraft Parking Aid) docking guidance system. The aircraft was operated as a public transport passenger flight with 5 crew and 93 passengers on board. As the aircraft approached the PAPA stop position, the first officer noted that a pushback tug parked ahead was “getting a bit close.” The commander immediately halted the aircraft, but during the stop heard a scraping sound and felt a slight bump. Post-flight inspection revealed that the lower section of the aircraft's radome had impacted the roof of the pushback tug. The stand docking guidance system indicated that the aircraft had stopped short of the normal stop position.
Contributing Factors
The ground crew had not expected the aircraft to use the stand's airbridge; instead, they intended for it to stop on ground marks positioned short of the normal PAPA guidance stopping position. The pushback tug had been parked within the area that should have been cleared of ground equipment before the guidance system was activated.
Aftermath
As a result of the incident, Edinburgh Airport issued a directive reinforcing existing Stand Entry Guidance procedures. The directive specifically stated that tugs are not to be pre-positioned in the stand tug lane prior to an aircraft's arrival, regardless of the guidance system in use. Additionally, the airline issued a procedure requiring flight crews to always follow AGNIS and PAPA indications when both are illuminated. If required to stop short of the normal position, crews are to do so only under marshalled guidance with the AGNIS switched off.