Pilot Suspected Of Error In Air Crash
Sydney Morning Herald
Monday July 3, 2000
The failure of one engine, exacerbated by pilot error which crippled the second engine, is the most likely cause of the Whyalla Airlines crash in which eight people died, the Herald has been told.
Rather than clear 21-year-old pilot Mr Ben Mackiewicz from blame, new evidence revealed by accident investigators has strengthened theories among pilots that inexperience was one of the critical factors in Flight 904's plunge into the Spencer Gulf on May 31.
It also points investigators to the deepening mystery of why both engines of the Piper Chieftan, inspected two days before the crash, could have failed with such devastating consequences.
The Australian Transport Safety Bureau released a report on Friday which found that both engines failed before the plane hit the water: ``Damage to the left engine included the failure of a connecting rod, together with a broken crankshaft. In the right engine, a piston had suffered significant damage," it said.
What has puzzled the investigators is how two engines, independent of each another, failed for different mechanical reasons at the same time.
The likelihood is that they did not fail at the same time, senior pilot sources say.
Instead, it was a combination of mechanical failure and human error rather than a ``million to one" mechanical coincidence.
Accident investigators, who have ruled out fuel contamination or lack of fuel, do not disagree with the explanation. But because of the complexity of the investigation, an official verdict will not be known for many months.
What pilot sources believe the report will conclude is that the left-hand engine failed shortly before 7pm as the lights of Whyalla came into view from the 6,000 feet altitude at which Mr Mackiewicz had been cleared to fly.
When an engine fails, pilots are taught to ``feather", or change the pitch of the propeller, to the angle of least resistance. This allows the plane to be flown safely on the other, operating engine, with maximum performance.
But Mr Mackiewicz, under some duress because of the left-hand engine failure, may have feathered the right-hand engine by mistake.
This, sources say, would have caused such stress on the engine that the piston would have broken, causing it to fail as well.
Shortly after 7pm, Mr Mackiewicz radioed to say that both engines had failed and he was going to have to ditch. At 7.04pm, just four minutes from the safety of Whyalla, the plane went down.
The head of the investigation, Mr Barry Sargeant, did not dismiss the theory, commenting that a twin engine failure for mechanical reasons alone was ``highly unusual".
``[The theory] is pure speculation but obviously we have to look at all the issues. We can't rule anything out until we do so," he said. ``The damage to the engines is consistent with it happening before the aircraft hit the water, which is unusual. At first inspection, the failures appear to be of a different sort."
The managing director of Whyalla Airlines, Mr Chris Brougham, has claimed the new evidence clears Mr Mackiewicz.
He said he was puzzled why the Civil Aviation Safety Authority had grounded his company's three other Piper Chieftans but no others in Australia.
The right-hand engine of the crashed plane had been rebuilt and had flown for 1,400 hours. The left-hand engine was new this year and had accumulated 300 hours. Both were inspected only two days before the crash in a routine check.
CASA's $1m boost Page 7
© 2000 Sydney Morning Herald
