Thai plane-crash inquiry probes wind-shear theory
Thai authorities probing a plane crash that killed 89 people in Phuket discovered on Tuesday that a system designed to check for dangerous winds was not fully working, an official said.
Attention had earlier focused on the pilot, with officials saying he had been warned of a dangerous wind shear by air-traffic control but decided to land anyway.
But investigators now believe the system to detect a sudden change in wind direction, which can throw a plane off course and then disappear, leaving pilots struggling to keep the jet under control, was not working properly.
“Initial assumption is that the wind-shear detection system of Phuket airport was not fully operational at the time the accident occurred,” said Vutichai Singhamany, a safety director at the Department of Civil Aviation.
“We checked today [Tuesday] and just found that the system didn’t respond to the control tower,” he said, adding that bad weather was also a possible cause of the accident on Phuket, an island popular with foreign tourists.
Chaisak Angkasuwan, head of the Department of Civil Aviation, however, urged people not to draw any conclusions until the investigation was complete.
“In my opinion, even if half of the wind-shear detectors did not work at the time, it did not necessarily cause the accident,” said.
Air-traffic controllers in Phuket told Indonesian pilot Arief Mulyadi, who was among the dead, that there had been reports of wind shear.
“There was a warning of wind shear from the pilot in the previous flight, which landed four minutes ahead,” said Kumtorn Sirikorn, vice-president of Aeronautical Radio of Thailand, an air traffic control body.
“Air-traffic control asked the pilot whether he knew about this wind shear or not, and he said he knew ... then the air traffic control official gave him additional information and asked him whether he still wanted to land or not.
“The pilot insisted he wanted to land.”
Sunday’s flight from Bangkok was approaching Phuket Airport in driving rain and wind when it slammed onto the runway before breaking up and skidding into a wooded embankment in flames.
The MD-82 jet was carrying 123 passengers and seven crew. Eight-nine people died, 57 of them foreigners.
Chaisawasd Kittipornpaiboon, who is leading the Transport Ministry’s crash investigation, said that in some cases it had taken up to three years to determine the cause of an accident.
He said officials were compiling evidence from the black boxes—which are due to be sent to the United States for analysis this week—as well as aircraft instruments and the voice recording between the pilot and the control tower.
“Wind shear is counted [as a possible cause] as it put sudden pressure on the aircraft,” he said.
Udom Tantiprasongchai, president of budget carrier One-Two-Go, which operated the doomed plane, admitted the airline bore some responsibility for the crash.
“It is too soon to jump to conclusions—it is unfair to our staff.
Please wait until the investigation is finished. But definitely it is partially our responsibility,” he told reporters.—AFP