Police interview passengers

The two passengers seriously injured in a light plane crash near Alexandra last week have spoken to investigators from their Dunedin hospital beds.

The focus of the investigation has now shifted to the aircraft's engine and fuselage, which arrived at a Transport Accident Investigation Commission (TAIC) facility in Wellington on Tuesday.

Glenorchy Air pilot Ray Crow died and two passengers survived when the Piper Cherokee 6 aircraft crashed near Poolburn Dam, about 20km east of Alexandra, during a scenic flight on August 5.

The passengers, Sarah and Erik Hoffmann, of the United States, were taken to the hospital in a serious condition.

TAIC chief investigator Tim Burfoot said investigators interviewed the pair on Saturday.

The information they had provided would be ''crucial'' to the investigation, as they described ''what they heard and saw and how the pilot was performing''.

At a funeral service for Mr Crow at Lake Hayes Pavilion on Tuesday, Glenorchy Air co-owner Robert Rutherford told mourners his senior pilot ''never cut corners and he never let us down''.

''I'm sure that in the last few moments before he died, he would have done everything he could, and that's why his passengers survived.''

Mr Burfoot said investigators began examining the wreckage yesterday with a ''fine-tooth comb''.

Tomorrow the engine would be removed and sent to independent assessors, who would put it on a test bed to see if it ran.

They would then ''tear it down'' so that each component could be checked and tested.

The initial information gathering phase in Otago was now complete, with investigators having interviewed Glenorchy Air staff and gathered company documents, including the aircraft's maintenance history.

As the investigation proceeded, investigators could return to the region to speak to those involved, he said.

Glenorchy Air said yesterday it would resume commercial flight operations on Saturday.