"The matter has been reported to the Coroner and the investigation into the crash is continuing," Senior Sergeant Matt Scoles, district deployment coordinator at southern police communications, said.
The Kabala's were "an incredibly well-known family" in the region, Gore District mayor Tracy Hicks said.
"I know there will certainly be a lot of the Gore community touched by this tragedy, and there will be a lot of rallying around and supporting the family through the challenge that's ahead of them," he said.
The couple are believed to have lived in Gore, and farming in the Waimumu area, all their lives.
"They are very strong members of that community," Mr Hicks said.
Mr Kubala was a former director of Southland Grain and Seed, which is now run by his son Kevin.
Mr Hicks described the company as a "long-standing institution in Gore".
People in the community were "surprised and shocked" to hear of the tragedy, he said.
The couple were "absolutely up there and enjoying life", Mr Hicks said, despite being in their 80s, "and to finish it in that way is not what any of us want for anyone".