Photo: 123RF
A report into a fatal plane crash in the South Island's Southern Alps last year reveals the pilot decided to turn back after his departure.
Franz Josef pilot Tim Gibb's light plane crashed at the McCoy Glacier on 4 August 2022 while he was on a flight from his home town to Rangiora in North Canterbury.
Search and Rescue (SAR) officials believed the crash was "not survivable" with Gibb's body unable to be recovered.
The Civil Aviation Authority (CAA) said, in its report released on Thursday, that Gibb's Cessna 182H Skylane collided with terrain after an apparent decision by the pilot to turn back.
It is now urging pilots to "upskill" for flying in mountainous terrain.
Aviation Safety deputy chief executive David Harrison said the crash was a devastating example of understanding the weather conditions along the entire planned route before taking to the sky.
"Particularly with mountain flying, we must acknowledge that once in the air, by the time we're able to conclude that it's unsafe to fly it may be too late. It's quite simple, if in doubt, don't fly," he said.
Franz Josef man Tim Gibb was killed when his plane crashed in the Southern Alps on 4 August 2022. Photo: Sharon Brettkelly
The CAA said Gibb had considered weather when planning the flight from Franz Josef to the Rangiora aerodrome.
However despite the weather forecast on the day of the flight, alongside concerns expressed by other pilots and his wife, he opted to go ahead with the flight.
"It appears the pilot did not fully appreciate the weather conditions to the east of The Divide," the report said.
The report said the aircraft likely encountered an area of very strong down-draughts resulting in a high rate of descent.
"It cannot be conclusively determined why the pilot decided to turn back; however, it was likely weather-related," the report said.
"When he did, it was too late to do so safely."
The down-draughts either exceeded its climb performance and/or forced it into the cloud layer.
For either scenario the pilot was unable to avoid terrain according to the CAA.
The 2022 tragedy prompted immediate community support for Gibb's family.
Nearly $60,000 has been raised on a Givealittle page with a number of tributes left for the pilot.
One of Gibb's two daughters was in Croatia when she found out about the crash, and some of the funds gathered were to cover the cost of her travel home.
The CAA report acknowledged Gibb was not required by Civil Aviation Rules to complete a mountain flying course, and his instructor believed he "understood the challenges of flying in high winds in mountainous terrain".
Harrison said the aviation rules set the minimum requirement for safety with instruction in terrain awareness techniques and basic mountain flying skills compulsory for private and commercial pilot licences.
"Mountain flying requires special skills, knowledge and flying techniques and we highly encourage pilots to seek additional opportunities to equip themselves for these conditions to avoid tragedy," he said.
The report urges pilots to familiarise themselves with the CAA Good Aviation Practice Mountain flying booklet before flying into mountainous terrain.