CAA will not carry out an onsite investigation.
"The CAA has spoken with the pilot and reviewed information and photographs taken by Police at the scene of the crash," he said in a statement.
"The pilot has confirmed to us there was no mechanical failure.
"He was flying over some large pine trees enroute to the vineyard. He lost sight of the ground and there was moisture on the cabin window which restricted visibility, requiring him to open the door to try and locate the ground. While doing this he hit a vineyard pole."
The CAA also confirmed the aircraft was a Guimbal Cabri and that the pilot was the sole occupant.
"We are satisfied that the cause of accident can be attributed to pilot error.
"Although any aviation accident is bad news, in this case the pilot is very lucky to have survived."
The findings back up commentary by an industry insider who told the Herald earlier today that it was likely due to pilot error.
The airline industry source, who is based near Wanaka, also confirmed the aircraft involved in the crash near Luggate just before 5am today was a Guimbal Cabri G2.
The source said he had spoken to the pilot and that he likely suffered a broken rib and a few bruises.
He likened the crash to that of a fender-bender on the road.
The source said the chopper was one of about 20 in the air carrying out frost-fighting procedures for one of the many wineries in the area.
The pilot, in his 60s, was able to walk away from the crash.
"There was probably about 20 helicopters out frost-fighting last night so he was just one of them."
The helicopters are used to fly over the vineyards and orchards to prevent the temperature to get down below freezing.
"The helicopter's just fly over top which brings the warm air down and keeps the orchard's above zero so it stops the fruit getting frozen."
The choppers hover from a height about 10m to 20m in the air which was why the pilot was able to walk away relatively unscathed, he said.
Central Otago Winegrowers Association president James Dicey manages the vineyard and said it was the fifth time frost-fighting there so far this spring.
"Having spoken to
the pilot, I think he was extraordinarily lucky to walk away from the crash.
"It was 4.30am, no moonlight so it was pitch dark, and if you lose your horizon, you
can get disoriented.
"I've been talking to him and obviously it was a fairly traumatic thing to go through, but he's doing okay, which is a relief because he's a bloody nice guy.''
Mr Dicey said the pilot was familiar with the area and had flown there before.
"I haven't checked yet for damage to the crops but that and any mechanical damage are all irrelevant so long as the pilot's okay.''
He would notify WorkSafe New Zealand about the crash and follow the appropriate process.
A police spokesperson said the pilot was taken to Dunstan hospital to be treated for his injuries.