By Andrew Probyn and Hannah Bowers
A Defence report into last year’s fatal helicopter crash has found there was a switch of pilots just two minutes before the Taipan smashed into the sea off Hamilton Island, killing all four army airmen.
Australian Defence Force inspector-general Margaret McMurdo is investigating the deaths of Captain Danniel Lyon, Lieutenant Max Nugent, Warrant Officer Phil Laycock and Corporal Alex Naggs, who died during a Defence exercise on July 28 last year when their Taipan helicopter crashed into the sea off Lindeman Island in the Whitsundays.
Multiple sources briefed on the Defence Flight Safety Bureau’s classified interim report have told 60 Minutes that investigators have effectively ruled out mechanical, engine or airframe fault as a cause for the crash.
However, analysis of the flight data has uncovered evidence that suggests pilot disorientation in the moments before the helicopter went down, and there is mounting suspicion that the helmet-mounted navigation visors called TopOwl may have contributed to it.
Defence’s own flight safety experts in 2019 said readings projected onto the TopOwl sight displays when the pilot looked left or right were ambiguous and inaccurate and were “a substantial risk of multiple deaths”.
The DFSB interim report found that just over two minutes before the Taipan smashed into the sea, Lyon had taken over the controls from co-pilot Nugent.
The chopper, codenamed Bushman 83, had been flying in formation with three other Taipans in a military exercise south of Hamilton Island.
Flying low in rain, with low clouds obscuring the moon and the horizon, the helicopters went into a holding pattern, beginning a series of left-hand turns.
Bushman 83 abruptly started to climb, before plummeting into the water at 130km/h.
From the top of its climb to impact was just six seconds, according to flight data analysed by the DFSB, 60 Minutes has been told.
The Taipan helicopter crew (clockwise from top left): Corporal Alexander Naggs, Lieutenant Maxwell Nugent, Warrant Officer Class 2 Joseph “Phil” Laycock and Commander Captain Danniel Lyon.
And it appears the pilot may have realised the aircraft was in significant peril in the split seconds before impact, desperately attempting to gain altitude.
This masthead has been told that the Taipan’s collective lift lever, which controls the down thrust of the helicopter by changing the angle of the blades, was adjusted from 18 degrees to 56 degrees, according to data extracted by the DFSB.
One experienced airforce pilot said this is suggestive of an “oh shit” moment from the Taipan pilot – a sudden realisation that the helicopter was in trouble.
The inquiry has heard that in the seconds before it smashed into the sea, the commanding officer in the rear helicopter of the formation urged Bushman 83 to gain height.
The wreckage of Bushman 83.Credit: 60 Minutes
“83, pull up, pull up, pull up,” the commanding officer ordered from Bushman 84 over the radio, before informing the formation, with alarm: “Fallen angel, fallen angel, 83 is in the water.”
Another pilot flying in the formation that night told the inquiry he experienced difficulty discerning the horizon in the TopOwl and that the symbology was giving unreliable readings.
“It gave the sensation that the aircraft was descending when it was in level flight,” the pilot, D5, told the inquiry.
“At the points of the flight where I could not see a visible horizon outside, sometimes that symbology, overwhelming would be the wrong word, but it kind of presented itself differently and I would get this feeling, like I know I’m in line with the aircraft in front of me but I’ve got a (symbology) vector telling me that I’m descending below the horizon.”
The interim DFSB report has been briefed to Defence headquarters, helicopter manufacturer NH Industries and aviation agencies.
McMurdo indicated on Friday she had also been briefed on the DFSB report.
Barrister Malcolm Gracie, who is representing Lyon, told the hearing he was disappointed to learn the families of the dead airmen had also been briefed by Defence on the DFSB report when he had not.
Gracie said the fact that some appearing at the inquiry had been told of DFSB’s interim conclusions put his job, and the job of other counsel representing the airmen, at an unfair disadvantage.
“The selective release of the contents of that DFSB interim report either had the intentional or inadvertent effect of causing a line of inquiry in this inquiry of which there is no evidence, but which points very squarely at possible pilot error, in circumstances where my client was either the flying pilot or at least the captain in charge,” Gracie said.
McMurdo said she was not empowered to release the DFSB interim report.
“I can assure you that there has been no leaking of this material from the inquiry or from those involved in the inquiry who have been permitted to see it,” she said.
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