Preliminary Singapore Airlines Turbulence Report
By Geoffrey Thomas Wed May 29, 2024
The Transport Safety Investigation Bureau of Singapore (TSIB) has issued its Preliminary Investigation findings of the Singapore Airlines SQ321 incident, which took place on 21 May and resulted in the death of one passenger with dozens injured inside the cabin on the Boeing 777-300ER aircraft.
The investigation team comprises TSIB investigators and United States representatives, from the National Transportation Safety Board (NTSB), Federal Aviation Administration (FAA) and Boeing.
The TSIB has extracted the data stored in the flight data recorder (FDR) and cockpit voice recorder (CVR) of the Boeing 777-300ER aircraft.
The investigation team has compiled a chronology of events based on preliminary analysis of the data from FDR and CVR and the preliminary findings for flight SQ321 which departed London on 20 May indicate that the flight was normal before the turbulence event. As per the preliminary findings at 07:49:21 hr (UTC) on 21 May 24, as the aircraft was passing over the south of Myanmar at 37,000 ft it was likely flying over an area of developing convective activity and beginning to experience slight vibrations due to vertical accelerations that fluctuated between +ve 0.44G and +ve 1.57G for about 19 sec.
The TSIB findings state that at the same time as the onset of the slight vibration, “an uncommanded increase in aircraft altitude, reaching a peak of 37,362 ft, was recorded. In response to this uncommanded altitude increase, the autopilot pitched the aircraft downwards to descend back to the selected altitude of 37,000 ft.”
The findings further state that the pilots also observed an uncommanded increase in airspeed which they arrested by extending the speed brakes. While managing the airspeed, at 07:49:32 hr, pilots called out that the fasten seat belt sign had been switched on.
JOIN: AirlineRatings.com YouTube Channel
GET: Accurate MH370 Information From AirlineRatings.com Newsletter
Airlineratings.com is packed with information about air travel and answers questions that many of us may have thought of, but didn’t know who to ask. Well, now you do!
Airlineratings.com was developed to provide everyone in the world with a one-stop shop for everything related to airlines, formed by a team of aviation editors, who have forensically researched nearly every airline in the world.
Our rating system is rated from one to seven stars on safety – with seven being the highest ranking. Within each airline, you will find the country of origin, airline code, booking URL and seat map information.
The rating system takes into account a number of different factors related to audits from aviation’s governing bodies, lead associations as well as the airline’s own safety data. Every airline has a safety rating breakdown so you can see exactly how they rate.
Over 230 of the airlines on the site that carry 99 per cent of the world’s passengers have a product rating.
Given that low-cost, regional and full-service carriers are so different we have constructed a different rating system for each which can be found within each airline.
Have questions or want to share your thoughts?
