Two Wanaka brothers have died in helicopter crashes just three months apart.

A Wanaka family linked for generations with flying are mourning a second son lost to a tragic helicopter crash in three months.

Pilot Nick Wallis died with his passengers – two Department of Conservation (DOC) staff – on Thursday in a heartachingly similar crash to the one that killed his brother Matt in July.

GEORGE HEARD/STUFF Pilot Nick Wallis and two Department of Conservation staff perished in a helicopter crash near Wanaka Airport. Pictured is the wreckage of the Hughes 500.

The trio left Wanaka Airport about 10.51am. They were headed north to carry out tahr control in the Haast area on the West Coast.

For reasons still unknown, the Hughes 500 helicopter crashed into farmland just north of the airport, near Stevenson Rd, and burst into flames. Emergency services were notified about 11am. No-one survived.

READ MORE: Chopper crash victim Matt Wallis remembered as larger than life

SUPPLIED Pilot Nick Wallis, left, with his father Sir Tim Wallis, has died after the helicopter he was flying crashed in Wanaka.

Only three months ago Nick Wallis gave a heart-rending eulogy at his brother Matt's funeral, saying it "physically hurts to know your life has been cut short".

Matt Wallis, 39, died when his Robinson 44 helicopter crashed into Lake Wanaka, near Stevensons Island, on July 21. He too had left Wanaka Airport, and was on a short solo flight to Mt Aspiring National Park. His body was retrieved two days later.

The Wanaka aviation community and DOC are said to be devastated after the latest crash.

Matthew Wallis' body was retrieved from the Stevenson Arm area of Lake Wanaka on July 23.

The Wallis men are the sons of aviation pioneer and Warbirds Over Wanaka air show founder Sir Tim Wallis and his wife, Lady Prue Wallis.

Warbirds Over Wanaka Community Trust chairman John Gilks called the crashes a "dreadful, double tragedy".

"It's really almost unbelievable that it's happened so soon after Matt's tragic death.

GEORGE HEARD/STUFF A police cordon was put up around the crash scene.

"To think that this has happened at all, within three months, I feel incredibly sorry for the whole Wallis family ... no family deserves that."

Nick Wallis, 38, was a "wonderful guy" and his death would be a "blow to the whole community".

"He was a gentleman and he was a man's man. He had a great sense of humour, just a nice guy to be around," Gilks said.

GEORGE HEARD/STUFF Matt Wallis, who died after his helicopter crashed in July, was taken for one last flight on the day of his funeral.

"They're such a well-known family and they have contributed so much to Wanaka and this region over many years, starting with Sir Tim and followed on by the four boys.

"This is going to be a bitter blow, a major blow and I'm sure there won't be very many people in Wanaka who don't feel exactly how I feel about it today."

DOC director general Lou Sanson said the tahr control operation had been put on hold. Sanson was devastated by the news and knew all involved.

THOMAS MANCH/STUFF Captain Tim Burfoot, TAIC chief investigator, speaks to media about the fatal helicopter crash near Wanaka airport.

"This is a tragedy for our staff who are like family and are passionate about the work they do." "Our hearts go out to the families of the DOC workers involved."

The Transport Accident Investigation Commission's chief investigator of accidents, captain Tim Burfoot, said TAIC was in the early stages of gathering information about the aircraft, the circumstances and the people on board.

Police said officers were working with other agencies to examine the area and recover the victims' bodies.

GEORGE HEARD/STUFF The funeral for Matt Wallis at Wanaka Airport in July. Nick Wallis is standing at the back, with Sir Tim Wallis and other family in the front.

The crash scene would be secured overnight. Wanaka Airport is still operating. Prime Minister Jacinda Ardern promised investigators would "get to the bottom of this crash as soon as we can".

TIM WALLIS A CRASH SURVIVOR

According to a 2005 Listener article, Tim Wallis has survived 15 air crashes, including hitting overhead power lines in a helicopter in 1968, breaking his back and permanently paralysing his left leg. He has been unable to fly since 1996, when he crashed his Spitfire Mk XIV at 320kmh at Wanaka Airport.

GEORGE HEARD/STUFF The Funeral for Matt Wallis, who died in a tragic helicopter crash in July.

Nick Wallis was the director and general manager of Alpine Helicopters. He was a licensed helicopter engineer, who had over 3000 flying hours experience.

Nick was the youngest of the Wallis brothers – his elder brothers being Toby, Jonathan and Matt. In a tribute at Matt Wallis' funeral, Nick said: "Being in business as brothers is not always as easy as it may appear from the outside.

"We of course had our challenges, but Matt you were a role model to me and your ability to split business and pleasure. We did not always agree but the four of us knew we had each other's backs covered."

GEORGE HEARD/STUFF Thousands of people turned out for Matt Wallis' funeral, held at Wanaka Airport, in July.

Alpine Helicopters spokesman David Hiatt said the company and Wallis' family were not in a position to comment.

Alan McKay, who was 1 kilometre away from the crash scene, said the remains of a fire were all that was visible.

"It's just a very, very sad day for Wanaka."

Johanna Mckenzie-Mclean/Stuff Police have set up cordons near the site of a fatal helicopter crash in Wanaka.

PRIME MINISTER PAYS TRIBUTE

Ardern said the crash was "an absolute tragedy".

"DOC staff go out every day working on our behalf and our environment – sometimes in really dangerous situations – and this is an absolute tragedy."

STUFF An ambulance leaves the cordon after a fatal helicopter crash near Wanaka Airport.

"People will want answers ... We will make sure we get to the bottom of this crash as soon as we can."

Conservation Minister Eugenie Sage said the department was working closely with police after the "absolute tragedy".

Sanson had flown south to help and support families of the men who died and she would do the same, Sage said.

"I have huge admiration for the skill, expertise and dedication of Department of Conservation staff and operators like the helicopter pilot. They were flying today and using their professional skills as part of their work to protect nature. Their loss is profoundly felt."

Waitaki MP Jacqui Dean gave her condolences to the families affected by the crash. "This is a huge shock and a terrible tragedy, which will impact the entire Wanaka community."

Alan McKay, who was 1 kilometre away from the crash scene, said the remains of a fire were all that was visible.

"It's just a very, very sad day for Wanaka."