A member of the Indonesian military looks out of the window during a search and rescue operation for Air Asia Flight 8501 over the Java Sea on Dec. 29, 2014.JUNI KRISWANTO/AFP / Getty Images
An airliner's abrupt disappearance over the Java Sea, as it flew through towering equatorial thunderstorms, points to another "loss of control" aviation disaster.
Floating objects and fuel slicks found close to the last radar echo of Indonesia AirAsia Flight 8501 – an Airbus A320 bound for Singapore from Surabaya, Indonesia's second largest city – has yet to be confirmed as coming from the doomed aircraft. But 36 hours after the plane vanished, hopes of finding survivors are slim.
(AirAsia Flight 8501: What we know so far about the plane's disappearance)
Massive thunderstorms are common in the tropics and pose a routine, albeit serious, challenge to flight crews. Modern jet airliners can survive even the most severe turbulence and multiple lightning strikes without structural failure, but flight crews are trained to fly around stormy areas to avoid their aircraft being tossed about. Deviation around, rather than over, is standard procedure and considered safer, since some tropical thunderstorms can reach far higher than commercial jetliners can fly.
At dawn on Sunday morning, about 50 minutes after takeoff, the twin-engined Airbus A320 was already at its planned cruising altitude and nearly halfway to Singapore, when one of its two pilots asked air traffic control for permission to climb from 32,000 to 38,000 feet. The request was initially denied because of other aircraft in the area. A few minutes later – at 6:17 a.m. local time – controllers offered Flight 8501 interim permission to climb to 34,000 feet, but there was no reply.
Airline incidents and fatalities since: 1975
No distress call was made and, until the cockpit voice and flight-data recorders are recovered, investigators won't be able to determine what exactly went wrong in the final few minutes of the flight.
"Based on the co-ordinates that we know, the evaluation would be that any estimated crash position is in the sea," Indonesia search and rescue director Henry Bambang Soelistyo said.
Search aircraft and ships from several nations converged on a 100-square-kilometre area between the island of Belitung, off Sumatra, and Borneo. The Java Sea is less than 100 metres deep where the aircraft vanished, which should make recovery of the flight recorders easier.
Flight 8501's fate – the sudden loss of a modern airliner without warning or distress call, as a seemingly capable crew crosses a zone well-known for powerful tropical thunderstorms – invites comparison with the 2009 crash of Air France's Flight 447. That crash killed all 228 on board the Paris-bound flight from Rio de Janeiro.
In the Air France crash, all three pilots, including a veteran captain and two less-experienced co-pilots, were so spatially disoriented that they were still arguing over which way was up when the Airbus A330 slammed into the sea. In just over four minutes, the undamaged and perfectly flyable aircraft fell more than 11 kilometres. The flight's autopilot had disengaged because of faulty airspeed readings, forcing the pilots to manually fly the aircraft.
AirAsia, a low-budget airline founded in 1993 by the flamboyant Malaysian entrepreneur Tony Fernandes, has redefined flying in Southeast Asia with a focus on low-cost, no-frills flights. Its distinctive fleet of red-and-white-painted Airbus A320s, with "Now Everyone Can Fly" emblazoned on the undersides, has become a familiar sight in Southeast Asian skies, and the airline had never suffered a fatal crash before.
Indonesian AirAsia, run by and 49-per-cent owned by the Malaysian AirAsia parent company, has another 28 Airbus A320s, each capable of seating 180 passengers. It was one of those aircraft that is missing and presumed lost at sea.
Mr. Fernandes flew to Surabaya on Monday, saying that until the investigation was completed it was premature to speculate on whether procedures or crew training needed to be changed.
On board the missing flight were 155 passengers, including 17 children and an infant. A crew of seven – two pilots, four flight attendants and, unusually, a flight engineer – were assigned to the flight.
The captain, Iriyanto, an Indonesian who uses only one name, was a former Indonesian air-force fighter pilot with more than 20,537 flying hours of which 6,100 were on Indonesia AirAsia Airbus A320s.
The co-pilot, Rémi Emmanuel Plesel, a relatively inexperienced French citizen who gained his pilot's licence at age 42, had 2,275 hours on the Airbus A320.
Usually one pilot flies a flight segment while another operates the radios and communicates with air traffic control. It's not yet known which pilot was handling the flight. However, in case of difficulties or unforeseen problems, the captain can, and usually does, take control.
The disappearance of Flight 8501 caps a catastrophic year for Malaysian aviation with three major crashes in unconnected incidents. Malaysia Airlines Flight 370, a Boeing 777 en route from Kuala Lumpur to Beijing, went missing on March 8 with 239 on board. It has never been found and may have been deliberately flown far from any land in the south Indian Ocean. On July 17, Malaysia Airlines Flight 17, another Boeing 777, was shot down by a surface-to-air missile fired from pro-Russian rebel-held territory in eastern Ukraine, killing all 298 people on board.
In Surabaya, Indonesian Vice-President Jusuf Kalla, told anxious relatives that the search by ships and more than a dozen aircraft was being hampered by bad weather.
Australia, Malaysia, Singapore and South Korea have sent ships and aircraft to join the search, and China offered to send planes and ships and any other help Indonesia needs.
Editor's note: A previous version of this article said incorrectly that AirAsia was founded in 1981. In fact, it was 1993.