An executive jet was reportedly flipped on to its back, rolled and plunged 10,000ft in mid-air but avoided crashing after hitting turbulence caused by a superjumbo.
The near-disaster, in which passengers were seriously injured and the Challenger aircraft damaged beyond repair, has accelerated moves by regulators to counter the danger caused by the wakes of big commercial aircraft.
The incident took place over the Arabian Sea in January, but was not disclosed until word spread in the aviation world, The Times reported.
The Bombardier Challenger 604, owned by Germany company MHS Aviation and carrying 11 passengers and crew, was flying at 34,000ft near Oman when it passed an Airbus A380, which is understood to have been an Emirates flight from Dubai to Sydney.
The superjumbo was flying 1,000ft higher in the opposite direction.
The Challenger was turned upside down and performed up to five complete rolls as it plunged towards the sea, according to accounts on aviation websites.
The pilots, whose skill has been praised, managed to stabilise the aircraft after cutting one of its two engines.
The aircraft landed in Muscat, with several injured passengers on board.
The incident, which is being investigated by the German air accident agency, has raised concerns that the Airbus 380, the world’s largest passenger jet, causes more danger than had previously been considered with its wake turbulence — vortices generated at aircraft wingtips which can act like horizontal tornadoes.
“With the A380 vs Challenger 604 incident, there is now growing concern amongst aircrews about the effects of the A380’s wake turbulence,” said the Flight Service Bureau, an information source for air operators.
Concern over the extent of the extra danger from the big Airbus arose in 2012 when a Virgin Australia Boeing 737 was buffeted by a nearby Emirates A380.
The danger of close wake encounters has been increased by navigation and air-traffic control technology that allows airliners to fly closer to one another and on precise paths.
The European Aviation Safety Agency is about to issue a bulletin to reduce the risk of such encounters in high-altitude cruises.
“Wake can be encountered up to 25 nautical miles behind the generating aeroplane,” says a draft of the EASA circular to EU airlines and air traffic controllers. “The encounters are mostly reported by pilots as sudden and unexpected events.”
It urges pilots to use their eyes to spot threats, among other measures.
“When possible, contrails [vapour trails] should be used to visualise wakes and estimate if their flight path brings them across or in close proximity,” according to the draft published on the Aviation Herald website.
EASA said that it had been working on the bulletin before the Challenger and Airbus incident and that the scheme was “not specific” to the A380, according to Flight International magazine.