What happened
On July 5, 2023, SriLankan Airlines flight UL 303, an Airbus A330-343 with registration 4R-ALP, was conducting a scheduled arrival from Changi International Airport, Singapore, to Bandaranaike International Airport, Katunayake. The flight was carrying 196 passengers and 14 crew members.
While the aircraft was on the ILS approach to Runway 22, the flight crew encountered wind shear conditions at an altitude of approximately 1,100 feet, roughly 3.5 nautical miles from the runway threshold. Upon detecting the wind shear and receiving an audio warning, the pilot in command initiated a go-around at 12:05 UTC. The crew requested a right turn to avoid a weather patch identified on the radar. Following instructions from Air Traffic Control, the aircraft climbed to 4,000 feet and subsequently performed a second approach, landing safely at 12:23 UTC.
The investigation
The investigation was initiated following a Mandatory Occurrence Report from SriLankan Airlines and subsequent complaints from local residents living near the Runway 22 approach path. These residents claimed that strong winds during the aircraft's approach had caused damage to several properties, including a house and a temple, and had resulted in minor injuries to one individual.
To analyze the event, the Civil Aviation Authority of Sri Lanka (CAASL) engaged the Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA) of France, along with experts from Airbus and EASA. Investigators examined flight recorder data (DAR) and analyzed the aircraft's trajectory and engine exhaust velocities. The investigation also reviewed meteorological reports from the Colombo and Katunayake offices, which had issued warnings for strong, gusty winds in the region on that day.
Findings
- The flight crew operated with valid licenses and followed standard operating procedures (SOP) during the wind shear escape maneuver.
- The aircraft maintained a valid certificate of airworthiness and registration.
- Low-level wind shear was the primary reason for the go-around.
- Severe weather conditions, including strong gusty winds, were prevalent in the Gampaha district at the time of the incident.
- Analysis of the aircraft's flight path and engine exhaust parameters confirmed that the go-around maneuver was not the cause of the reported property damage; the damage was attributed to the prevailing heavy winds in the area.