Synopsis
The incident involving the loss of standard minimum separation between ALK122 and FDB1026 occurred on 9 January 2024 at Bandaranaike International Airport, Katunayake, Sri Lanka. It was reported to the Civil Aviation Authority of Sri Lanka (CAASL) by the air traffic controller involved through a mandatory occurrence report on the same day. An investigation team was appointed by CAASL. The General Civil Aviation Authority (GCAA) of the United Arab Emirates, being the State of Registry and State of the Operator for one aircraft, and the Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA) of France, as the State of Manufacture for the aircraft involved in SriLankan Airlines flight ALK122, were notified and accredited representatives were appointed.
Factual Information
FDB1026, a scheduled flight from Bandaranaike International Airport to Male International Airport, Maldives, was issued explicit instructions by Colombo Approach Control to follow the Standard Instrument Departure (SID) procedure. The initial clearance was provided before engine start-up, and reaffirmed at 05:54:22 UTC when FDB1026 was identified by radar and cleared to ascend to flight level 240 via the SID. The pilot-in-command (PIC) confirmed receipt at 05:55:24 UTC. However, the aircraft failed to comply with the vertical restrictions mandated by the SID, resulting in reduced separation from ALK122, an inbound flight from Chennai International Airport, India, operating under Instrument Flight Rules. As the loss of separation developed, the air traffic controller provided traffic information to both aircraft. FDB1026 acknowledged the information, but had already climbed to 4,300 feet, triggering the Short-Term Conflict Alert (STCA) in the Air Traffic Management system. At the same time, ALK122 maintained 5,000 feet, marking the breach of separation.
Personnel Information
Pilot-in-Command of FDB1026: Age 42, holder of a valid Airline Transport Pilot License (ATPL-A-71694) issued by the Director General of GCAA-UAE, with ratings for IR/MPA and B737 300-900. Total flying experience: 9,891 hours, with 6,603 hours on type. Duty time in the 48 hours prior to the incident was not specified.
First Officer of FDB1026: Age 32, holder of a valid Commercial Pilot License (CPL-A-115863) issued by the Director General of GCAA-UAE, with ratings for IR/MPA and B737 300-900. Total flying experience: 564.34 hours, with 99.05 hours on type (previous flying). Duty time in the 48 hours prior to the incident was not specified.
Air Traffic Controller: Holder of a valid ATC license (ATC/132) issued by DGCA Sri Lanka, valid from 25 August 2023 to 24 August 2025, with multiple ratings including Aerodrome Control, Approach Control Procedure, Area Control Procedural, Approach Control Surveillance Radar, and Area Control Surveillance Radar. English Language Proficiency Level 5 valid until 27 July 2026.
Communications
The flight crews of both flights were established on two-way communication with Colombo Approach Control on frequency 132.4 MHz.
Flight Recorders
Digital Flight Data Recorder (DFDR) analysis reports were provided by GCAA-UAE to the investigation team. Raw Quick Access Recorder (QAR) data from ALK122 was shared with BEA, and an analysis report was obtained.
Organizational Information
Airport and Aviation Services (Sri Lanka) (Private) Limited is the appointed Statutory Service Provider to provide Air Traffic Service under the Civil Aviation Act No. 14 of 2010. The Civil Aviation Authority of Sri Lanka is the regulator responsible for registration and issuance of certificates of airworthiness.
Conclusions
The investigation identified the following causes: 1. The failure of the PIC of FDB1026 to comply with the ATC clearance instructions, specifically to adhere to the altitude restrictions of the Standard Instrument Departure (SID) procedure. 2. The air traffic controller's delayed intervention to correct the deviation.
Safety Actions
The report includes safety actions taken by the involved organizations, but details are not specified in this summary.
Safety Recommendations
The report includes safety recommendations directed to relevant parties to prevent recurrence of similar events.