Singapore Airlines flight turbulence: Aircraft fell 54m in five seconds, suffered ‘rapid change’ in G-force, report finds

Passenger died and 28 are being treated in Thai hospitals following incident on London to Singapore flight on May 21st

Preliminary findings released on Wednesday of an investigation into a Singapore Airlines flight hit by severe turbulence last week showed a rapid change in gravitational force and a 54m altitude drop caused injuries.

A 73-year-old male passenger died of a suspected heart attack and dozens were injured after flight SQ321, flying from London to Singapore, encountered what the airline described as sudden, extreme turbulence while flying over Myanmar.

The May 21st flight carrying 211 passengers and 18 crew diverted to Bangkok for an emergency landing after the Boeing 777-300ER plane was buffeted by turbulence that flung passengers and crew around the cabin, slamming some into the ceiling. Four Irish citizens were on board the flight.

“The aircraft experienced a rapid change in G (gravitational force) ... This likely resulted in the occupants who were not belted up to become airborne,” Singapore’s transport ministry said in a statement on the report by the country’s Transport Safety Investigation Bureau.


“The vertical acceleration changed from negative 1.5G to positive 1.5G within 4 seconds. This likely resulted in the occupants who were airborne to fall back down,” it said, citing information extracted from the flight data and cockpit voice recorders.

“The rapid changes in G over the 4.6 seconds duration resulted in an altitude drop of 178ft [54m], from 37,362ft to 37,184ft. This sequence of events likely caused the injuries to the crew and passengers,” it added.

Shaken passengers described scenes of chaos in the minutes after the incident, with the turbulence throwing people upwards then into the aisle, many left with bleeding and head wounds.

Photographs of the cabin showed gashes in the overhead cabin panels, oxygen masks and panels hanging from the ceiling and luggage strewn around. A passenger said some people's heads had slammed into lights above the seats and broken the panels.

Singapore Airlines said it acknowledged the report and was co-operating fully with the investigation. “We are committed to supporting our passengers and crew members who were on board SQ321 on that day, as well as their families and loved ones,” it said in a statement on Wednesday.

The airline late on Tuesday had said 45 people who were on board the flight were still in Bangkok, including 28 passengers receiving medical treatment in hospital.

Among those initially hospitalised were patients with spinal cord injuries and some with brain and skull injuries, according to Thai medical officials.

The preliminary report said that upon the flight encountering slight vibrations there was an uncommanded increase in altitude, resulting in the autopilot pitching the aircraft downwards. The pilots experienced an increase in airspeed and responded by applying speed brakes.

“While managing the airspeed ... it was heard that a pilot called out that the fasten seat belt sign had been switched on,” it said.

The investigation team comprised Singaporean investigators, representatives from Boeing and United States officials from the National Transportation Safety Board and the Federal Aviation Administration. The Singapore transport ministry said the investigation was ongoing.

Last Sunday, six passengers and six crew members were injured following turbulence on a flight from Doha, Qatar, to Ireland.

It is understood the turbulence occurred about two hours into the seven-hour flight, when the aircraft was travelling over Turkey. The Qatar Airways flight landed safely as scheduled in Dublin shortly before 1pm on Sunday. – Reuters