Monday, November 07, 2011

‘Over-speeding’ propellers blamed for Dash 8 disaster


THE fatal Airlines PNG Dash 8 crash on Oct 13 near Madang was caused by the “over-speeding” of both propellers, a preliminary report of the Papua New Guinea Accident Investigation Commission has found, The National reports.
The commission said the propellers exceeded their maximum permitted revolutions per minute by more than 60%.
It said because of this there was a loud “bang” which witnesses on the ground reported hearing.
The flight crew then shut down both engines.
“At 5.17pm the crew made a mayday call to air traffic control and indicated they were having an in-flight emergency and that both engines had stopped.
“Madang tower then declared a search and rescue phase, believing the aircraft was about to ditch into the ocean.
“But the aircraft landed on a sparsely timbered terrain on the northern side of the Buang River, 33km southeast of Madang town, killing 28 of the 32 people on board.”
The report said that on impact, the plane was badly damaged while colliding with trees and the ground and an intense fuel-fed fire started.
Villagers who had heard and seen the aircraft in the final stages of its descent rushed to the crash site to find the fuselage engulfed in flames.
They then helped the four survivors and took them to the nearest aid post.
The preliminary report was released last Friday by the commission’s acting chief exec­utive officer Sid O’Toole, who said they had met the requirement for a preliminary report to be ready within 30 days.
It said the pilot in command, 64, and his 40-year-old first officer had 18,200 flying hours and 2,750 flying hours respectively, with both holding valid PNG airlines transport pilot licences.
The report said the flight progressed normally and flight P2-MCJ was transferred to Madang air traffic control at 5.10pm on descent into Madang.
“The descent profile on this sector was steep because of the proximity of the Finisterre Ranges to Madang and the pilot, who was the handling pilot, was hand-flying the aircraft because the autopilot was unserviceable.”
The report said the pilot was manoeuvring the aircraft visually to avoid cloud and thunderstorms.
At 5.12pm, in response to a request from Madang tower, the flight crew stated that the aircraft was 24 nautical miles from Madang, leaving 13,000ft on descent.
O’Toole said: “The Dash 8 has a turbine engine which runs through a gear box and it runs through the propellers and over-speed caused self-destruction.
“The investigations have been supersonic and we thank Prime Minister Peter O’Neill for visiting the site and we are glad that O’Neill has made a commitment to release funds to complete the investigation,” he said.
“We thank TropicAir for their help in this time.”
Civil Aviation Minister Puri Ruing thanked the commission, the Aviation Transport Safety Bureau of Australia, the Transport Safety Board of Canada, aircraft manufacturer Bombardier, engine manufacturer Pratt and Whitney, the Civil Aviation Safety Authority of PNG (CASA) and Airlines PNG for their cooperation and help in enabling the investigation to progress
efficiently and effectively, resulting in the preliminary report being issued in under 30 days.
“The accident investigation will continue for some time in order to establish root casual factors for the accident and the final report may take a year to complete due to the detailed analysis that is required,” Ruing said.
The information in the preliminary report was derived from initial investigation of the occurrence.
However, people were cautioned that there was the possibility that new evidence may become available that altered the circumstances described in the preliminary findings.

1 comment:

  1. Anonymous12:23 PM

    Both props overspeeding on a Dash 8? At the same time? Sounds like a clear case of the handling pilot slamming the power levers into the beta range inflight - a Flight Manual No No! Cross check against his KIAS...I bet you will find he was over the 242 KIAS, causing the warning horn to sound, and over reacted.