In between, there have been at least six other casualties and 30 crashes.
Ms Barns said her husband had a bigger helicopter that he often took her up in, but he never let her ride the R22.
"I quite liked that bigger one. But this was touchy. He wouldn't even let me on a flight with that little one," she said. "I just don't like them."
The R22 helicopter carrying her husband and a friend plummeted upside-down after an "uncorrected low-g situation", says a coroner's report. The pilot would have felt weightless as the helicopter entered freefall at the top of a climb.
A final report on the accident has not been produced by the Civil Aviation Authority.
"It's quite frustrating to not know what actually happened, but I told them to close it, for the family, six months ago," Ms Barns said.
She wants pilots to avoid the helicopters so their families will not have to go through what she did.
"I would rather people fly the bigger helicopters. These little ones are touchy. People need to be very cautious with them," she said.
"My husband was very good. He was a very careful pilot."
There are 164 R22 helicopters registered in New Zealand, and 30 crashes have been recorded by the Civil Aviation Authority in the past six years.
The R22's four-seater sibling, the R44, of which there are 161, has crashed eight times during that period.
Together, they make up about half of all helicopters in New Zealand.
Transport Accident Investigation Commission air accident investigator Peter Williams said they were cheaper machines and pilots needed to know their limits.
"They are low-performance, low-power, and limited in what they can do."
They were often used for training and agriculture, which on the face of it seemed to expose them to higher risk, he said.
Aviation Industry Association chief executive Irene King said private operators often lost perspective and pushed the helicopters over the edge.
"The sort of accidents that are occurring are really things we should know better about, "some plainly silly stuff," Ms King said. "When you're out there on your own, you can convince yourself of a lot of things."
Commercial operators had learned to stay within the manufacturer's performance guidelines and had not had a crash in recent years, she said.
Mentoring programmes have been made available by the industry for pilots who fly on their own.
Special certifications for the R22 and R44 have also been created, which pilots must complete before taking passengers.
Special training is necessary because the R22 is more responsive to controls than other helicopters, says a special investigation report by the United States National Transportation Safety Board.
"Flight instructors probably do not have sufficient time to react to R22 students' large, abrupt flight control inputs," it says.
But both Ms King and Mr Williams stressed that, given the number of Robinsons in New Zealand, they did not crash more often than other helicopters.
Recent crashes seemed to all have different causes, Mr Williams said, and there was no evidence that the model was to blame.