What happened
On the night of 12 December 2002, a Garuda Indonesia Boeing 737-300, registration PK-GGG, was taxiing at Singapore Changi Airport for a scheduled flight to Jakarta. The aircraft was following instructions from Air Traffic Control to proceed via Taxiway N3 and Taxiway NC3 toward Runway 02R. The weather at the time involved moderate to heavy rain and night conditions.
As the aircraft entered Taxiway NC3, the co-pilot spotted a maintenance vehicle, operated by SIA Engineering Company Limited, moving at a high rate of speed on an adjacent roadway. The vehicle turned toward the aircraft's path, prompting the co-pilot to alert the pilot-in-command to stop. Although the pilot applied the brakes, the aircraft struck the vehicle. The impact caused the aircraft's nose gear doors to buckle and break, while the vehicle's roof and left door were crushed by the aircraft's forward fuselage.
There were no injuries among the 109 people on board the aircraft or the driver of the vehicle.
The investigation
The investigation examined the movement of both the aircraft and the vehicle, the visibility conditions, and the regulatory framework for airside driving. Investigators analyzed the timing and positioning of the collision, noting that the aircraft was taxiing at approximately 12 knots. The investigation also reviewed the functionality of the traffic light systems at the junction and the adequacy of the signage provided to ground drivers.
Findings
- The collision was caused by the failure of the vehicle driver to maintain an adequate look-out for aircraft movement on Taxiway NC3.
- The driver had stopped at the designated stop line but failed to observe the aircraft, which was within his field of view as he proceeded to cross the taxiway.
- The aircraft and the vehicle were both in proper working order, and the flight crew had followed all ATC instructions correctly.
- While the driver was aware of the requirement to yield to aircraft, the space and time analysis indicated the aircraft was visible to the driver during his crossing maneuver.
Safety action
Following the incident, the Civil Aviation Authority of Singapore (CAAS) implemented several changes, including:
- Updating the "Rules & Regulations for Airside Drivers" to ensure consistency with Aerodrome Regulations.
- Improving the dissemination of Apron Notices to ensure all airside drivers are informed of current requirements.
- Reviewing and improving the reliability of the traffic light systems at the North Cross Taxiways area.