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A report into the last of the crashes, on September 12, 2016, at Mt Sale, north of Arrowtown, was released by the Transport Accident Investigation Commission (TAIC) yesterday.
It found the helicopter's approach was "relatively fast, low and close to the landing site".
"This is a technique that might not give pilots enough time to confirm the actual wind before landing, nor does it ensure that their intended escape routes remain usable throughout the approach," the report states.
The crash was The Helicopter Line's fourth serious landing crash in three years.
One of the passengers, an Australian man, suffered a minor injury to his knee.
The helicopter was substantially damaged.
On the day of the crash the weather was clear, and The Helicopter Line was undertaking tourist flights in the area.
One of the flights was to take five passengers to Mt Vanguard.
Soon after take-off the pilot saw the weather had deteriorated in that direction, and changed the destination to Mt Sale.
"He said that the approach proceeded normally until the final stage, when the rate of descent suddenly increased, so he increased the power to go around. Although the helicopter responded to the pilot's control inputs, it struck the ground hard with the landing gear and the main rotor blades, and came to rest on its left side."
TAIC found the helicopter was operating normally. The pilot had the required training and experience for the flight.
It identified The Helicopter Line had had four serious landing accidents in three years.
"While there were some similarities in the circumstances, the factors for most of these accidents were not determined conclusively by the commission's inquiries or by the operator's internal investigations."
TAIC recommended the chief executive of The Helicopter Line, with the New Zealand Civil Aviation Authority, review its safety management system audit process to ensure its safety policy, safety assurance, risk management, and promotion of safety were sound.
Other key lessons raised were that human factors could have "both positive and negative effects on situational awareness", and it was important for pilots to remain vigilant for changes in environmental conditions.
Mark Quickfall, chairman of The Helicopter Line owner Skyline Enterprises, said the company had begun a safety audit review process before the report was released.
Mr Quickfall will meet TAIC officials in May to discuss the company's review process.
"Any accident for a tourism provider is a concern," he said.
"We're very keen to make sure our operations are robust."
The pilot involved in the crash was no longer working for the company, Mr Quickfall confirmed.
He declined to say whether that was because of the incident.
The company had not had any serious landing crashes since September 2016, he said.
Auckland man Jerome Box (52) died and seven people were injured in 2014, when a Squirrel helicopter operated by another Skyline subsidiary, Harris Mountains Heliski, crashed west of Lake Wanaka.
- Daisy Hudson