Passengers on board a Sydney-bound Qantas A380 Airbus were reminded of the importance of 'buckling up' when the aircraft struck severe turbulence during a flight on 9 January 2012.

About three hours from Singapore, the Captain switched on the seat belt lights as the aircraft was being manoeuvred to keep clear of thunderstorms. Moments later, the aircraft encountered two very short, but severe sets of turbulence.

Despite the severity of the turbulence, only seven passengers were injured in the incident. None of these passengers were wearing seat belts -- most of the injured were believed to be walking through the cabin when the turbulence struck.

The low number of injuries was most likely because the vast majority of passengers were seated with their seat belts fastened before the turbulence hit. In fact, media coverage of the incident quotes several passengers who noted how fortunate they were for having their seat belts fastened during the event.

In another incident in October 2008, a Qantas Airbus A330 en route from Singapore to Perth suddenly pitched down while in-flight due to a rare technical problem in the aircraft's systems. At least 60 passengers, who were seated without their seat belts fastened, were injured.

Although some of those wearing a seat belt were also injured, most of the injuries occurred when unrestrained occupants were thrown into the aircraft's ceiling. The injury rate and severity was much greater for those who were not wearing a seat belt.

More information

Further information on the wearing of seat belts and other advice for minimising injury risk during turbulence and other in-flight upsets is available in the ATSB Aviation Safety Bulletin Staying safe against turbulence available on the ATSB website.

Public safety advice about the importance of wearing seat belts on aircraft is also provided by the Australian Civil Aviation Safety Authority.

A video showing the effects of not wearing seat belts during a simulated in-flight upset is available on the US Federal Aviation Administration website.

Passengers not wearing a seat belt were flung from their seats as a Qantas Airbus A330 suddenly pitched down in October 2008. The fittings above the seats were badly damaged from the unrestrained passengers.