History of the Flight
On 24 February 2022, a Eurocopter EC135P2 helicopter, registration PK-RJH, operated by PT. Ekspres Transportasi Antarbenua, was preparing for a non-scheduled flight from Seletar Airport, Singapore, to Hang Nadim International Airport, Batam, Indonesia. At 1229 hours local time, the pilot-in-command (PIC) informed the Ground Movement Controller on-the-job trainee (GMC OJT) that the helicopter was ready to air-taxi for departure. The GMC OJT, who was monitored by a qualified OJT instructor, issued a taxi clearance for the helicopter to air-taxi to Holding Point E4 for Runway 03. No clearance was given to enter the runway.
The PIC air-taxied from parking bay B56 along Taxiway Echo Papa to Holding Point E4, but instead of stopping, continued onto Runway 03 and lined up with the runway, awaiting take-off clearance. The PIC later stated that before entering the runway, he checked that no other aircraft were on approach or on the runway.
Communication
The GMC OJT issued the taxi instruction, expecting a proper readback. In three transmissions, the PIC did not include the phrase "holding point" in his readbacks. The GMC OJT believed she heard the PIC mention "holding point" after the third attempt, but the communication record showed he did not. The OJT instructor noticed the improper readback but did not request a correction.
The GMC OJT, OJT instructor, and Runway Controller (RWC) observed the helicopter entering the runway without clearance. The RWC instructed the GMC OJT to direct the PIC to contact the tower frequency. The PIC did so, and the RWC informed him that no clearance had been given to enter the runway. The PIC apologized for the mistake. The RWC subsequently issued take-off clearance, and the flight continued without further event.
Personnel Information
The PIC, aged 51, held an Airline Transport Pilot Licence-Helicopter issued by Indonesia's Directorate General of Civil Aviation, valid until 31 March 2022. He had 4,110.5 total flying hours, with 81.8 hours on the EC135 type. The GMC OJT, aged 28, had three years of total experience and was under training. The OJT instructor, aged 32, had eight years of experience as an aerodrome controller.
Aerodrome Information
Seletar Airport's runway holding points, including E4, are equipped with red stop bar lights controlled via the Airfield Lighting Control Management System. When illuminated, they indicate pilots must not enter the runway. At the time of the incident, these lights were switched ON. The PIC reported in a post-incident interview that he did not recall seeing any red stop bar lights during the taxi.
Analysis by TSIB
The investigation examined two aspects: the reading back of taxi clearance and failure to notice the red stop bar lights. The PIC consistently omitted the key phrase "holding point" in his readbacks, which has significant safety implications in ground movement control. The GMC OJT attempted to obtain a proper readback but was mistaken in believing she had received one. The OJT instructor acknowledged not intervening despite noticing the incomplete readback. Additionally, the red stop bar lights were active, but the PIC did not recall seeing them, which contributed to the incursion.
The Transport Safety Investigation Bureau classified this occurrence as an incident. No injuries or damage to the aircraft were reported.