A Qantas Airways Airbus A330-300 jet takes off from Sydney International Airport over the skyline of the city, on December 18, 2015. REUTERS/Jason Reed/File photo RTX2R40T
Passengers have described the terrifying moment a vortex sent their Qantas flight in a 10-second “dive.”
Hundreds of shocked passengers held hands to believe that they would die when the plane suddenly dropped over the Pacific Ocean on Sunday.
The dramatic trial where the passengers on QF94 from Los Angeles to Melbourne is considered to be caused by the vortex, or “wake turbulence” caused by another aircraft that departed just two minutes earlier.
QF94 passenger Janelle Wilson told The Australian the “three-quarter-full” aircraft suddenly entered a free fall dive … a direct decrease in the direction of the sea” for about 10 seconds.
“It was between 1½ and two hours after we left LA and all of a sudden the plane went through heavy turbulence, and then all the way over and we were nosediving,” Wilson told the newspaper yesterday.
“We were all lifted from our seats immediately and we were in a free fall. It was that feeling like when you are on the top of a roller coaster, and you just have a road on the edge of the peak and you start with the head downwards.
“It was an absolute feeling of losing your stomach, and that we are nosediving. The lady sitting next to me and I screamed and held hands, and just waited, but thought it was with absolute certainty that we were going to crash. It was terrible.”
Fortunately, no one on board the aircraft, with a capacity of 484, was injured.
The QF12 flight took off from Los Angeles at 11:27 pm Sunday night, 57 minutes behind schedule. While the QF94 service, which started at 11:29 hours, 49 minutes late, landed safely but 30 minutes late in Melbourne at 8 pm on Tuesday.
According to the flight safety experts on SKYbrary, wake vortexes severe turbulence, which is generated by the passage of another aircraft in flight. In principle, there is not sufficient separation between the flights.
However, a spokeswoman for Qantas told The Australian there was no violation of the separation standards, because the two A380 aircraft were understood to be dispensed by 20 nautical miles and 1000 feet in height.
There are several incidents of wake vortices cause serious injury and even death after pilots have lost control of the aircraft.
“A cross-track encounter along the way, is probably only one or two sharp ‘jolts’ as the vertebrae are crossed,” the SKYbrary site states. “In the en route case, injuries to unsecured residents may result, both of passengers and the cabin crew.
“Since most of the operators to ensure that passengers are insured during the interim and final approach and during initial climb after take-off, the cabin crew, who are most at risk of injury if they are not secured during the later stages of an approach.”
In 1993, the crew of a domestic passenger charter flight in California has failed to provide sufficient separation between their aircraft, a Boeing 757 and lost control or their aircraft which crashed killing all occupants and destroying the aircraft in the impact and post-crash fire.
More recently, in 2008, an Air Canada Airbus A319 travel across the northwest of the USA unexpected sudden wake vortex turbulence from an in trail Boeing 747-400.
Pilots then responded with potentially hazardous flight control inputs which led to a disturbance of the aircraft trajectory.
An unintended descent of 465 metres followed. Because cab service was underway and the seatbelt signs were left off led to cabin service carts hitting the cabin ceiling and several passengers were injured, some seriously.
Wake turbulence was also the fault of the near-stall of a 747 from Qantas flight from Melbourne, 68 km from Hong Kong, in April of last year.
Last year, the German Federal Bureau of Aircraft Accident Investigation called for an urgent review of aircraft separation standards after a near-disaster when a private jet was hit by the wake turbulence of a Sydney-bound Emirates A380 above the Arabian Sea.
This story was previously published in the news.com.au.