Mr Stott worked for Wanaka Helicopters as a flight instructor and was training Mr Hoogvliet, a licensed pilot, for his commercial licence.
They died when their Robinson 22 crashed in very windy conditions south of Bow Peak in the Mt Aspiring National Park on Wednesday afternoon.
TAIC communications manager Peter Northcote, of Wellington, said yesterday the inspectors would remain in Wanaka over the weekend to interview people and collect documentary evidence.
The inspectors had looked at the pattern of debris and identified what parts of the wreckage they wanted removed for further technical analysis in a workshop, he said.
"They will be working with the aircraft owners and insurers to lift out the wreckage, most of which we will want to keep for a while," Mr Northcote said.
While the investigation could take up to a year, if the inspectors found anything that warranted an urgent safety recommendation, they would not hesitate to make that, he said.
It was too early to say what caused the accident and Mr Northcote said the commission would not speculate. The three main areas of any investigation centred on the people flying the machine, the machine itself and the environment they were in, Mr Northcote said.
It took about a year to complete an investigation because of commission workloads and the technical nature of transport accidents, he said.
"The reality is, investigators are working on more than one case at a time. We can't predict when they happen ... Typically, we have to wait for test results and research. We consult with other jurisdictions overseas.
"A year is very reasonable by international standards. Other jurisdictions can take longer," Mr Northcote said.
• Inspectors are working on 33 cases at present, including Wednesday's accident.
The commission chose not to investigate a 2006 fatal helicopter accident at Homestead Peak (also in Mt Aspiring National Park) because the Wanaka Helicopters Robinson 22 machine had been hired for a private sightseeing flight, as distinguished from Wednesday's flight, which was a commercial operation.
Two men died in the Homestead Peak accident, Wanaka-based pilot Keith McKenzie (29), of Canada, and American tourist Jonathan Stein (61).
The Civil Aviation Authority is in charge of the Homestead Peak investigation and a final report is imminent, CAA communications adviser Bill Sommer said yesterday.
Coroner Alan Macalister's inquest into the men's death has been on hold since January, pending the final CAA report.
The report has taken a long time to produce because of the complex crash scene at high altitude.
The accident caused an alpine tussock fire and aircraft debris was scattered across a wide area.
Bad weather also hampered initial investigation efforts.
Mr Sommer said the CAA would not release the draft final report to the public. That decision would rest with the coroner.
