The fire that broke out in the engine of a Skymark Airlines jetliner just after takeoff from Kagoshima airport in December 2005 was likely caused by sulfur particulate attaching to the turbine blades, a Japan Transport Safety Board panel said Friday.
The Japan Transport Safety Board, part of the Land, Infrastructure, Transport and Tourism Ministry, said in a report that the sulfur particulate may have been part of yellow sand containing volcanic gas and sulfides.
The sulfur, which differed from the volcanic ash of Sakurajima, an active volcano near the airport, would have corroded the blades and induced metal fatigue, the board said.
On Dec. 1, 2005, the pilots of the Boeing 767 bound for Tokyo were warned the right engine was on fire immediately after takeoff just before 3 p.m.
The plane returned to the airport as the engine broke apart, spraying metal fragments over the ground. None of the 90 passengers and crew members was hurt.
Although dozens of cases of problems arising from jetliner engines sucking in volcanic ash have been reported around the world, it is rare for sulfur particulate to cause corrosion inside an engine, the safety board said.
The board said there are “many opportunities (for planes) to be inclemently affected by sulfur in Japan, where yellow sand flows up in the air and where there are many active volcanoes,” and urged airlines to wash their planes’ engines proactively.
According to the report, a 14-cm blade — one of 74 high-pressure turbine blades in the rear of the engine — detached due to metal fatigue and damaged the inside of the engine further by hitting other blades.
‘Takeoff’ miscued
Miscommunication between an air traffic controller and the captain of a Japan Airlines jet prompted the plane to start its takeoff roll at New Chitose Airport in Hokkaido without clearance last February, a government panel said in a report released Friday.
The Japan Transport Safety Board, part of the transport ministry, said the Air Self-Defense Force controller used the word “takeoff” prematurely, prompting the captain to think he received permission to move onto the runway for takeoff.
The controller said to the plane, “Expect immediate takeoff,” indicating the Boeing 747 would soon be cleared to depart, without realizing the terminology is generally used by the tower only when granting or canceling takeoff permission.
The copilot and trainee in the cockpit had doubts about the captain’s decision to move onto the runway but did not attempt to intervene, the board reported.
The Land, Infrastructure, Transport and Tourism Ministry will revise operation standards shortly to stipulate that the term “takeoff” should be used only when issuing or canceling a formal clearance.
The jet, bound for Tokyo’s Haneda airport with 446 people on board, started its takeoff roll at around 10:30 a.m. on Feb. 16. just moments after another plane from Kansai airport landed on the same runway and had yet to turn off. It stopped after about 500 meters following an order from the tower to abort.