S I N G A P O R E, Dec. 15, 2000 -- U.S. investigators have concluded that pilot suicide likely caused a 1997 SilkAir plane crash that killed 104 people, contradicting findings by Indonesian authorities.
In a Dec. 11 letter to Indonesian investigators, NationalTransportation Safety Board chairman Jim Hall said there was nothing wrong with the Boeing 737 and “the accident can be explained by intentional pilot action.”
The nearly new Boeing 737-300 crashed into the jungle on Dec. 19, 1997, killing all 104 people aboard. The Singapore-bound flight plunged to the ground from 35,000 feet shortly after leaving Jakarta, Indonesia’s capital.
On Thursday, Indonesian investigators ruled out pilot suicide in a final report on the crash. Singapore officials said they accepted that report’s findings. SilkAir is a subsidiary of Singapore Airlines.
But the U.S. investigators had a different take.
“The evidence suggests that the cockpit voice recorder wasintentionally disconnected,” the NTSB letter said. It added that “recovery of the airplane was possible but not attempted.”
A separate report from the U.S. board argued that the planecould not have acted as it did without deliberate action from the pilot.
“It is very likely from the time it departed from cruise flight until the end of the recorded data that the airplane was responding to sustained flight control inputs from the cockpit,” the report said, rebutting the Indonesian claims.
The report said wreckage showed the plane’s engines were set to high power and that controls were set to a “nose-down” position.
A day earlier, Singapore police and Indonesia’s NationalTransportation Safety Committee had issued separate statements saying Singaporean pilot Tsu Way Ming showed no suicidal tendencies.
The final Indonesian report said investigators were unable to determine the cause “due to the highly fragmented wreckage and the nearly total lack of useful data, information and evidence.”
In-flight data and voice recorders were disabled moments before the crash but showed no signs of “unusual behavior,” it said.
Both pilots were properly trained, licensed and well-rested, the Indonesian report said. It said there “was no evidence found to indicate that the performance of either pilot was adversely affected by any medical or psychological conditions.”
But the U.S. board said Tsu “was experiencing significantfinancial difficulties” and that the pilot had been reprimanded by airline management several times in the weeks before the crash.
It said the Indonesian report failed to analyze information about the pilot’s financial debts, calling the omission “disappointing.”
Even though the plane crashed in Indonesia, the U.S.was asked to participate in the investigation because the plane was made by Seattle-based Boeing Co.
Legal actions have been filed against the plane’s manufacturer, Boeing, by the relatives of more than 50 crash victims. A number of families have also filed claims against SilkAir.