All part of the service: Dave Greenberg in front of the rescue helicopter.

He's been saving lives since he was a teenager and has been a crew member of Wellington's Westpac rescue helicopter since 1991, but modesty is still Dave Greenberg's watchword.

"It's just in my nature, being in service to others," he said.

"Over the 20 years I've been doing this I get a lot of the credit because I tend to do the media stuff."

But the 48-year old Life Flight crewman, and operations manager for the Wellington region, said: "I'm part of a team. It's always a team effort and I'm only one part of that."

Typically the team comprises the pilot, a crew member and either a paramedic or a doctor.

Mr Greenberg said his was a multi-function role.

"One aspect is to assist the pilot with navigation or radios ... when we fly at night we use night-vision goggles, which requires specialty training in that area." Winching was another technically demanding aspect.

His involvement with the emergency services began non-professionally. "The first life I saved was when I was 13," he said, referring to a man he resuscitated in his native New York. "That was a real turning point for me."

He continued to be involved in a volunteer capacity, while pursuing a career in IT. In 1990 he took a job with Unisys in Wellington.

"I was unsure about coming out," he said of the big move.

"I figured it was only for one year. I've always been a bit of a risk taker ... and this one worked out fantastically."

In 1991 he applied to Life Flight as a volunteer, and in 1995 it became a permanent paid role.

"I found my life's passion at Life Flight, in a country I love."

Wellington, he said, had everything he needed.

Despite leaving his family behind in the United States, he has surrounded himself with friends. "This is where my life is."

His said his job was challenging but satisfying, involving mostly hospital transfers and search and rescue missions.

"Even when you come across things that aren't very pleasant, it's part of the job. I'm very lucky – I believe in what I'm doing."

The missions that stuck in his mind were sea rescues, he said.

"They're usually in pretty bad conditions, which makes it challenging."

Despite this, Mr Greenberg said he had never feared for his life.

"I feel much safer in the helicopter than I do crossing Lambton Quay.

"There are inherent risks, but a lot of money is spent on training, and every decision about safety is made as a team."

One mission that did not turn out the way he expected was the rescue of a critically ill seaman on New Year's Day, 2005.

Having retrieved the man from a boat competing in the Global Challenge competition, Mr Greenberg was offered his spot on board for the next leg of the race.

He jumped at the chance. "I ended up in an unfamiliar workplace. It was pretty memorable, and all thanks to my job."

The role was more challenging when missions became personal.

"Just recently I picked up a horse-riding victim who turned out to be Kerry Prendergast's son," he said – a heart-rending experience because he is a long-time friend of the family.

The service handled 1300 patients last year and this year will hit the 20,000-mission mark.

"We're making an incredible difference to a huge number of lives, one at a time," he said.

Mr Greenberg has been involved in 3500 of the rescues.