Transport Accident Investigation Commission (TAIC) chief investigator Tim Burfoot said the commission's medical consultant was liaising with the doctors at Dunedin Hospital treating Sarah and Eric Hoffman, of the United States.
''When the doctors say they're up to it, they will be interviewed, but not before tomorrow,'' Mr Burfoot said yesterday.
The pair, both in their 30s, were taken to the hospital in a serious condition after the crash, which claimed the life of Glenorchy Air senior pilot Ray Crow, of Queenstown.
The pair said in a press statement yesterday they wished to thank everyone for their concern.
''We are focusing on our recovery, we have sympathy for Ray and his family, and have no further comment to make at this time.''
Deputy chief investigator Peter Williams and air accident inspector Sam Stephenson, both of Wellington, spent Wednesday examining the crash site near Poolburn Dam, about 20km east of Alexandra.
Mr Burfoot said the wreckage was removed and put in storage in Wanaka the same day. It would be taken to a facility in Wellington for detailed analysis. The investigation was still gathering information and it was too early to reach even preliminary conclusions.
Yesterday investigators gathered documents from Glenorchy Air and began interviewing the company's staff. The interviews would continue today if required, he said.
The investigation was expected to take about a year, but ''serious safety issues'', if any were found, could be raised before the final report's release.
