What happened
On 12 July 2015, at approximately 02:25 local time, a Japan Airlines Boeing 767-300ER, registration JA-606J, attempted to take off from a taxiway at Singapore Changi Airport. The aircraft was scheduled for a flight to Tokyo Haneda.
During the taxi phase, air traffic controllers instructed the crew to "taxi on the greens," utilizing the airport's green taxiway centerline lighting system. While the crew intended to follow a specific route to Runway 2/0C, they inadvertently turned onto Taxiway EP. Upon receiving clearance to line up and take off, the crew began the take-off roll on the taxiway. A runway controller noticed the aircraft accelerating on the wrong surface and immediately ordered the crew to stop. The pilots responded by reducing thrust, bringing the Boeing 767-300ER to a safe halt. There were no injuries to the 208 persons on board, and no other aircraft or vehicles were endangered.
The investigation
The investigation focused on why the flight crew failed to recognize they were on a taxiway rather than the runway. Investigators examined the "taxi on the greens" guidance system, the communication between the crew and air traffic control (ATC), and the crew's mental model of the taxi route.
Key elements examined included the pilot's interpretation of ATC instructions regarding departure timing, the effectiveness of the visual guidance lights, and the sequence of clearances issued by the runway controller. The investigation also reviewed the crew's reliance on the green lights versus external visual cues like signage.