Singapore Airlines SQ32 Turbulence Incident: Preliminary Findings Released

Singapore's Transport Safety Investigation Bureau (TSIB) has released preliminary findings on the recent turbulence incident involving Singapore Airlines flight SQ32. The flight, which left London on May 20, experienced heavy turbulence on May 21 while flying over southern Myanmar at an altitude of 37,000 feet. More than 100 people were injured due to the sudden changes in gravitational force, and one passenger died of a heart attack. Currently, 28 passengers are still in hospital in Bangkok, where the flight was diverted.

The investigative team, which includes representatives from the National Transportation Safety Board, the Federal Aviation Administration and Boeing, has been analyzing data from the flight data recorder and the cockpit voice recorder. The preliminary report reveals that the flight was operating normally until the turbulence began. The plane experienced slight vibrations due to fluctuating gravitational forces and an uncommanded increase in altitude, which the researchers attributed to the development of convective activity in the region.

The autopilot banked the airplane down to return to the selected altitude of 37,000 feet, and the pilots extended the airspeed breaks to counter an uncommanded increase in airspeed. The report says that a pilot announced that the seat belt sign had been activated, but the passengers on board did not notice and the cabin crew continued with their meal service. This discrepancy will likely be part of the ongoing investigation.

The researchers determined that the uncontrolled changes in altitude and airspeed were likely caused by an updraft. The plane experienced a rapid change in gravitational forces, dropping from +1.35G to -1.5G in 0.6 seconds, likely sending unbelted passengers airborne. The gravitational force then went from -1.5G to +1.5G in four seconds, causing the passengers to fall back down. This fall is the most likely cause of serious injuries.

Since the incident, Singapore Airlines has implemented safety changes, including suspending hot drink and meal service when the seat belt signal is on. Crew members will secure all loose items and equipment in the cabin during bad weather and ensure that passengers return to their seats and fasten their seat belts. The airline has said that the safety of passengers and crew is of the utmost importance, and that they will continue to review their processes.

While airlines do their best to navigate known and controllable causes of in-flight turbulence, it is sometimes unavoidable and dangerous. The simple practice of always wearing your seat belt while sitting on an airplane can protect you from these unpredictable events.