Investigation into turbulence in flight over Singapore shows sharp drop in altitude caused injuries By Reuters

SINGAPORE (Reuters) – Preliminary findings of an investigation released on Wednesday into a Singapore Airlines (OTC:) flight hit by severe turbulence last week show that a rapid change in gravity and a fall of 170 feet (54 meters) led to injuries.

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

A Boeing (NYSE:) 777-300ER flight with 211 passengers and 18 crew on board on May 21 was diverted to Bangkok for an emergency landing after the plane was hit by turbulence that sent passengers and crew flying around the cabin, hurling some against the ceiling.

“The aircraft experienced a rapid change in G-force (gravitational force) … This likely resulted in the occupants who were not wearing seat belts being ejected into the air,” the Department of Transportation said in a statement on the Transport Safety Investigation Bureau report.

“The vertical acceleration changed from minus 1.5 G to plus 1.5 G within four seconds. This probably caused the occupants who were still in the air to fall back down,” it said, citing information from the flight data and the voice recorders in the cockpit.

“The rapid changes in G-forces over a period of 4.6 seconds resulted in a decrease in altitude of 54 m (178 feet), from 37,362 feet to 37,184 feet. This sequence of events was the likely cause of the injuries to the crew and passengers,” it said.

CHAOTIC SCENES

Shocked passengers described scenes of chaos in the minutes following the incident. The turbulence threw people into the air and then into the aisle. Many were left with bleeding and head injuries.

Photos of the cabin showed cracks in the ceiling panels, oxygen masks and panels hanging from the ceiling, and luggage scattered everywhere. One passenger said some people hit their heads on the lights above the seats, breaking the panels.

Singapore Airlines said it had taken note of the report and was cooperating fully with the investigation.

“We are committed to supporting our passengers and crew who were on board SQ321 that day, as well as their families and loved ones,” it said in a statement on Wednesday.

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

According to Thai doctors, among the patients initially admitted to hospital were patients with spinal cord injuries and some with brain and skull injuries.

The preliminary report stated that during the flight, an uncontrolled increase in altitude occurred due to slight vibrations, which caused the autopilot to steer the aircraft downward. The pilots noticed an increase in airspeed and responded by applying the airbrakes.

“While we were checking the airspeed, a pilot could be heard calling out that the fasten seatbelt sign had been turned on,” it said.

The investigation team included investigators from Singapore, representatives from Boeing, and U.S. officials from the National Transportation Safety Board (NTSB) and the Federal Aviation Administration (FAA). Singapore’s Ministry of Transport said the investigation was ongoing.