‘Insufficient speed’: Aviation expert weighs in on Rottnest seaplane tragedy

Collins said that while all aircraft differed, a pilot would usually undergo training to fly a specific aircraft type.

Was wind a factor?

Bureau of Meteorology daily recorded observations shows the wind speed at Rottnest Island at 3pm on Tuesday was 48km/h, the highest it had been recorded at that time in the last week, but some wind gusts of 69km/h had been recorded at other times.

“It did look a little bit a little bit choppy, maybe that’s why he rotated a little bit early,” Collins said.

“But it looks like he was close to being into wind. Whether he saw something in the water, whether there’s a rock, there’s an obstacle, whether there’s something he tried to get out of the water early, I just don’t know.”

Collins said lack of forward speed has caused the plane to nosedive.

“He rotated too early and the aircraft didn’t have enough forward speed and when you don’t have enough forward speed, the airflow over the wing is no longer laminar, it becomes turbulent in the air,” he said.

“People think that air goes under the wing to make an airplane fly. Actually, an airplane is almost sucked up into the air.

“The air going over the top of the wing is fast, and it creates low pressure which allows the aircraft to climb.

“So once you’ve got any deterioration in the quality of the air going over the wing, which could be caused by insufficient speed, too much angle of attack, it gets turbulent, then you lose lift, and that’s when you get a stall.”

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Officers from the Australian Transport Safety Bureau are expected to arrive at the island on Wednesday to investigate what went wrong.

Investigators would speak to the four remaining survivors and any other witnesses, and would collect relevant recorded information including available flight tracking data, as well as pilot and aircraft maintenance records, and weather information.

Two parts of the plane have been recovered. The pontoon was found on a beach a couple of kilometres from the crash site, and police took another piece of the wreckage to a forensic holding yard.

Collins said the Cessna 208 Caravan was one of the most popular and safest planes of its type.

“The Caravan is certified for and regularly configured for float plane operations. It is also certified to fly single engine IFR and is used for cargo operations in all legal weather conditions in the USA day and night,” he said.

“It is powered by a Pratt and Whitney PT6 engine, the family of which has logged half a billion flight hours.”

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