Lost plane's request to change course denied
The plane sought permission to climb above threatening clouds. Air traffic control couldn't say yes immediately — there was no room. Six other airliners were crowding the airspace, forcing AirAsia Flight 8501 to remain at a lower altitude.
Minutes later, the jet carrying 162 people was gone from the radar without ever issuing a distress signal.
The last communication from the cockpit to air traffic control was a request by one of the pilots to climb from 32,000 feet to 38,000 feet because of the weather. The tower was not able to immediately comply because of the other planes, said Bambang Tjahjono, director of the state-owned company in charge of air traffic control.
The twin-engine, single-aisle plane was last seen on radar four minutes after the final communication.
When planning a route prior to takeoff, pilots try to avoid thunderstorms. But if one pops up during the trip, or crews encounter rough turbulence, they routinely ask to fly around storms or move below or above the turbulence.
A storm alone isn't going to bring down a modern plane designed to withstand severe weather. But weather paired with a pilot error or a mechanical failure could be disastrous. It's like a car driving on a highway during a thunderstorm. Plenty of vehicles get through bad weather safely but one that gets a flat tire or takes a turn too fast might crash.
Pilots rely on sophisticated weather-radar systems that include a dashboard display of storms and clouds, as well as reports from other crews, to steer around dangerous weather.
"A lot more information is available to pilots in the cockpit about weather than it ever was," said Deborah Hersman, former chairman of the U.S. National Transportation Safety Board. But the technology has limits and sometimes information about storms "can be a little bit stale."
The suspected crash caps an astonishingly tragic year for air travel in Southeast Asia, and Malaysia in particular. Malaysia-based AirAsia's loss comes on top of the still-unexplained disappearance of Malaysia Airlines Flight 370 in March with 239 people aboard, and the downing of Malaysia Airlines Flight 17 in July over Ukraine, which killed all 298 passengers and crew.
"Until today, we have never lost a life," AirAsia group CEO Tony Fernandes told reporters. "But I think that any airline CEO who says he can guarantee that his airline is 100 percent safe is not accurate."
Indonesian President Joko "Jokowi" Widodo ordered an immediate review of all aviation procedures.
Nearly all the passengers and crew are Indonesians, who are frequent visitors to Singapore, particularly on holidays.
Ruth Natalia Puspitasari, who would have turned 26 on Monday, was among them. Her father, Suyanto, sat with his wife, who was puffy-eyed and coughing, near the family crisis center at Surabaya's airport.
Suyanto remembers the concern his daughter showed for the families of the Flight 370 tragedy.
Authorities suspect MH370 was deliberately diverted by someone on board and ultimately lost in a remote area of the Indian Ocean with notoriously deep water.
Flight 8501 vanished over a heavily traveled sea that is relatively shallow, with no sign of foul play.
The captain, Iryanto, who like many Indonesians uses a single name, had more than 20,000 flying hours, AirAsia said.
"Papa, come home, I still need you," Angela Anggi Ranastianis, the captain's 22-year-old daughter, pleaded late Sunday in social-media comments that were widely quoted in the Indonesian press.
People who knew Iryanto recalled that he was an experienced military pilot, flying F-16 fighters before shifting to commercial aviation. His French co-pilot, Remi Plesel, had been in Indonesia three years and loved to fly, his sister, Renee, told France's RTL radio.
Debris has been found in the search for missing AirAsia flight QZ8501 as the mission to recover passengers and investigate the tragedy continues.
