Turbulence incident: Global warming causing worse turbulence ?
Severe turbulence struck a South African Airways plane that was heading to Hong Kong, injuring 20 people before the aircraft landed safely on Wednesday, the airline said.
Medics were waiting at the Hong Kong airport to assist passengers on SA286, which had departed Johannesburg on Tuesday, the airline said in a statement.
Television footage showed rescue workers wheeling one injured passenger on a stretcher.
Three crewmembers and 17 passengers were injured, airline spokesman Tlali Tlali said.
The Hong Kong fire department said two people were critically injured. The victims were taken to three hospitals.
SAA Airbus 340-300
The airline said 165 passengers were on the Airbus 340-300 when the turbulence hit the aircraft as it flew over Kuala Lumpur, the Malaysian capital
Last year in a similar incident about two dozen people on two flights were injured when their aircraft hit turbulence before landing at Hong Kong's airport.
Thai Airways said 20 people were hurt when an Airbus A38-800 carrying 500 passengers, two pilots and 24 cabin crew from Bangkok encountered "unforeseen turbulence" as it was descending to Hong Kong's airport.
The airline said passengers and cabin crew suffered injuries but the plane landed safely. 39 were reported injured but the airline later revised the number to 20. Kung says the injured were sent to three hospitals in the southern Chinese city.
Hong Kong Airlines reported three passengers and three flight attendants were hurt when their flight from Phuket hit "sudden turbulence" as it neared the city's airport. The airline said the plane landed safely and the six have left hospital. The plane was carrying 110 passengers and seven crew.
Clear air turbulence:
The most insidious kind of turbulence, clear-air turbulence, is invisible, comes without warning and occurs any time during a flight. One of the main culprits of clear-air turbulence is the boundary between the jet stream—that aerial river that forms where arctic air masses meet warmer air from the south—and the slower-moving air adjacent to it. This invisible boundary shifts unpredictably, and woe to any unstrapped passenger in a jet that crosses it. "If you're flying in clear air, you have no indication at all. If an aircraft has passed through the area ahead of your airplane, your pilot might get an advance warning of turbulence ahead. "But if you're an early morning flight and you're going through an area first, you're going to be 'Probe One.'"
Even the worst turbulence is no cause for alarm—by itself. I don't think an airplane has ever broken up in flight because of turbulence. All planes are built to withstand much more than even a severe turbulent event."
Which makes passenger safety when an airplane hits turbulence—especially without warning—primarily the responsibility of the passengers themselves. That means buckling your seat belt, just as the pilots and stewardesses recommend, anytime you're seated. Air travelers should not get complacent. The best thing to do is to not loiter around in the aisles of the airplane," he says. "Do what you need to do, then get back to your seat and put on your seatbelt. You're still hurdling through the air at 500 miles an hour; things can happen. in 2005 an Air Korea jet fell 100 m in clear air turbulence, causing significant injury. Passengers and objects effectively become airborne, and go into free-fall until they hit something.
There has also been an unprecedented increase in turbulence involving aircraft in Australia.
The Australian Transport Safety Bureau said turbulence doubled over the three-month period between October to December 2013, compared to the previous three months, significantly above the five year historical average.
Turbulence is the leading cause of in-flight injuries and an increase directly affects the safety of cabin passengers.
But the ATSB could not speculate as to why it was happening, according to Dr Stuart Godley head of the ATSB's Aviation Research Team.
"During the last five years there has been an increase in reporting, particularly from cabin crew, about an increase in turbulence, but we don't know why this is occurring," he said.
"Because they are weather-related, these events are cyclical.
"We're used to seeing more of them in summer, but this increase is unprecedented."
Turbulence is caused by the irregular movement of air and often cannot be seen.
When air masses with different speeds, direction or temperatures meet each other, turbulence is likely to occur.
While turbulence is normal and occurs frequently, it can be dangerous - especially for passengers not wearing seat belts or carrying unsecured items.
That was the case for one passenger in November 2013 who sustained a serious head injury from a laptop computer that fell from an overhead locker during a turbulent flight to Sydney.
Another passenger was injured after being struck by an iPad. Passengers not wearing seat belts are more likely to be seriously injured when turbulence hits.
"Serious head injuries can be sustained when a person hits the overhead panel where luggage is stored because they did not wear a seat belt," he said.
"Cabin crew have had legs broken from walking around the cabin when turbulence hit," he said.
Clear air turbulence (CAT) can pose a great amount of danger as it cannot be detected and hit any time, which is exactly what happened when cabin crew were commencing a meal service during a flight from Cairns to Tokyo in 1996.
Passengers, crew and meal trolleys hit the ceiling of the aircraft and landed heavily, seriously injuring passengers who were not belted up. Bone fractures, lacerations, neck and back strains, dislocated shoulders and shattered teeth were reported. Four were admitted to hospital.
While nothing that extreme has been reported during the recent bout of increased turbulence, Godley warns passengers to keep their seat belts on in the off-chance it should happen. Some areas of Australia are more prone to turbulence and Sydney has been a common spot for it to occur over the last summer, Godley said. "122 incidences of turbulence were recorded, 35 of which occurred on flights in to and out of Sydney, which seems to be a hot-spot for turbulence," he said. "Brisbane and the Gold Coast is another area which experiences a high amount."
Global warming to blame?
New research has found global warming is likely to double the chances of plane turbulence in the coming decades.
According to a study from the University of Reading and the University of East Anglia, atmospheric changes could lead to the amount of turbulent air patterns that affect planes doubling, and for the intensity to get stronger by the middle of this century.
Dr Paul Williams, who headed the research, said global warming would have a significant impact on the aviation industry. "Air turbulence does more than just interrupt the service of in-flight drinks. It injures hundreds of passengers and aircrew every year - sometimes fatally.
"It also causes delays and damages planes. The total cost to society is about US$150 million (NZ$177 million) each year." Researchers used supercomputer simulations to analyse jet streams over the North Atlantic Ocean.
Dr Manoj Joshi, from East Anglia, said they focused on looking at turbulence in its peak periods. "Our research focused on clear-air turbulence in winter. This is especially problematic to airliners, because clear-air turbulence is invisible to pilots and satellites, and winter is when it peaks."
It found the chances of encountering significant turbulence would increase by between 40 per cent and 170 per cent, but most likely double, and the intensity by anywhere between 10 and 40 per cent.
Williams said any increase in turbulence would make flying more uncomfortable and increase the risk to passengers and crew. Airlines would also be forced to re-rout some flights to avoid stronger patches of turbulence, which would lead to greater fuel consumption and emissions of atmospheric pollutants, make delays at airports more common, and ultimately push up ticket prices.
The research showed the atmosphere was becoming more vulnerable and unstable, and Williams said the aviation industry was partly to blame for that.
What is turbulence ? Turbulence explained in a previous blog (click link)