Singapore Airlines SQ321 Fatal Turbulence Incident Over Myanmar – Weather Radar Investigation
Impact Assessment Rationale
MEDIUM: High-row recalibration. The Singapore Airlines SQ321 turbulence event creates Aviation Liability, passenger injury, potential hull and regulatory exposure. Impact is not HIGH absent hull loss, fleet-wide grounding, product-liability finding, major claims estimate, or market-wide aviation pricing response.
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Geographic Zone Matches
2 active matches
- EU Sanctions ListRule-basedConfidence 100%
- High Piracy Risk - Strait of MalaccaRule-basedConfidence 100%
Geographic zone matches are RiskEvents spatial/analytical indicators, not coverage determinations or Lloyd's official classifications.
Summary
Singapore Airlines flight SQ321, a Boeing 777-300ER (9V-SWM), encountered severe clear-air turbulence over southwest Myanmar on 21 May 2024 while en route from London Heathrow to Singapore, resulting in one fatality and 56 serious injuries. Singapore's Transport Safety Investigation Bureau is investigating whether a weather radar 'underpainting' malfunction failed to display hazardous conditions to the crew. The aircraft diverted to Bangkok, and subsequent testing revealed possible intermittent radar underpainting. Investigators have recommended development of cockpit weather radar recording capability, which is currently absent on pre-2023 certified aircraft types.
This summary is AI-generated from linked source reports and may change as more information becomes available. See our correction policy for how to report errors.
Structured Intelligence
known
- SQ321 (9V-SWM) suffered severe turbulence at 37,000ft over southwest Myanmar on 21 May 2024
- One passenger was fatally injured; 56 other occupants were seriously injured
- The aircraft was a Boeing 777-300ER operating London Heathrow to Singapore
- The aircraft diverted to Bangkok following the incident
- Both navigation displays were set to 320nm range at the time of the encounter
- The turbulence encounter lasted approximately one minute, including 21 seconds of manual flight
- 12 reports of weather radar underpainting were found in fleet maintenance records from May 2023 to July 2025 across ~29,000 flights
- Two prior underpainting reports related to the incident aircraft were filed on 29 April and 1 May 2024
- ICAO requires crew-machine interface recording only on large aircraft certified after 1 January 2023
- No weather radar image recording capability existed on this aircraft
reported
- The commander reported no clouds in the immediate flightpath and no weather returns on navigation displays prior to the event
- After the upset, weather returns were still absent above 31,000ft but appeared below that altitude
- During a ferry flight on 26 May 2024, crew observed possible radar underpainting and photographed the displays
- The investigation team opines the radar was painting weather returns intermittently during the occurrence flight
uncertain
- Whether the weather radar was definitively underpainting conditions at the time of the turbulence encounter remains unconfirmed
- The radar manufacturer disputes the validity of ferry-flight tests and claims no evidence of malfunction during the incident
- Investigators noted 'some unusual behaviours' during extensive radar testing but no conclusive findings have been published
Affected Countries
Key Entities
Sources
Trade Media
- FlightGlobal21 May 2026, 16:34
Timeline
Status changed to monitoring
Auto-transitioned: no updates for 6 hours
Lifecycle changed
active → monitoring
Lifecycle changed
signal → active
Status changed to active
remediation: existing authoritative signal
Impact changed
high → medium
Initial Detection
Singapore Airlines flight SQ321, a Boeing 777-300ER (9V-SWM), encountered severe clear-air turbulence over southwest Myanmar on 21 May 2024 while en route from London Heathrow to Singapore, resulting in one fatality and 56 serious injuries. Singapore's Transport Safety Investigation Bureau is investigating whether a weather radar 'underpainting' malfunction failed to display hazardous conditions to the crew. The aircraft diverted to Bangkok, and subsequent testing revealed possible intermittent radar underpainting. Investigators have recommended development of cockpit weather radar recording capability, which is currently absent on pre-2023 certified aircraft types.
The inquiry into the accident points out that there was no means of recording the weather radar images presented to the crew...the commander was 'surprised' as no clouds had been observed, nor had there been weather returns on the navigation display — even with the 'gain' knob set to maximum.
Source: FlightGlobal (Trade Media) · View source