"In most disabled sports I need help," Ewen says. "I couldn't go biking by myself whereas with skiing I can drive up the mountain, get my sit-ski out, go on the slope and go home. I love the independence.
"I was thrilled to find skiing gives me the same kind of feeling as riding my bike over rough stuff."
Ewen is a picture of ruddy alpine health, but he knows what bleak looks like.
"When I got out of the spinal unit I went home and back to school, but it didn't really work out. I got a job for a while, then moved to Wanaka for a change of scene.
"After the injury it wasn't the same with all my friends still riding. Then one of my mates took me skiing at Ruapehu. I loved it."
In Wanaka, Ewen met Jody Blatchley, a man who suffered a similar injury.
"We started sit-skiing together and it was the best season ever. He was a nutter too, who was keen on cutting loose. Then I went across for the American season and got into racing, before spending a couple of months free skiing."
Ewen will train in the United States and compete in their early season competitions to whittle his points down to Olympic qualification standard.
"You start with 1000 points, and the aim is to reduce them to see how much you're behind the world leader. It depends on who turns up at the races, and beating better athletes. I might find out whether I'm going to the Games at the last minute.
"Life is pretty good at the moment. I'm rolling with it."
Carl Murphy stands at the opposite end of the competitor lifecycle to Ewen.
At 38, with a wife, two children, and a third on the way, the architectural designer finished fourth in the snowboard cross at the Sochi Olympics. He intends to add bank slalom for these Games.
Murphy is missing half his right leg, so wears a prosthesis in competition and day-to-day life, although the two limbs differ in construction.
"The snowboarding one [lower leg] is stock standard to what the general public would get in terms of set-up, but it is three-times stronger with extra layers of carbon fibre. The foot goes up the grades in terms of stiffness, too, so it can take more of a load rather than shattering under pressure.
"It's the back foot on my snowboard so I need to rely on it reacting effectively to my movements. I use my knee and hip more to make those adjustments.
"I use Allen keys to take [the foot] on and off. Up the mountain I unscrew one foot, put it in my bag, and screw the other one on."
Murphy grew up with his disability but says he has never lacked for competitive instinct.
"I think it was part of my genetic make-up. I just had to work harder to keep up with my mates. That's helped shape the athlete I am; I've never seen myself as any different."
Murphy's point about normality rings true in the country's high performance sport environment.
Paralympics New Zealand received an extra $550,000 this year, from $1.7 million to $2.25 million. The boost came on the back of their 21-medal haul - nine gold, five silver and seven bronze - at the Rio summer Games. That is the second-most medals picked up by a Kiwi team after the 25 of 1984; nine golds equalled the best previous performance from 1996. New Zealand rose to 13th on the medal table, beating their 16th in 2004.
"I think the general public is recognising these aren't just 'poor disabled people'. This is high performance sport and para-athletes try just as hard as anyone.
"Finding the right balance can be tough sometimes, but it's easier for me because I run my own business and work at home [in Wanaka] fitting the hours around my training. It's relatively flexible because much of the work is electronic."
Murphy received a drop in funding this year after suffering injury, so his architectural work has taken up more time lately.
"Most years I've made a steady income from snowboarding, but I didn't get the results I wanted last season.
"The upside is I've recovered to be stronger and fitter."
Adam Hall is a veteran of the New Zealand Paralympic ranks. At 29, he has attended three Games starting at Turin in 2006, and will have endured 28 consecutive winters come March in Korea.
He was diagnosed with spina bifida at birth, but describes himself as "lucky" because he can walk.
He competes in the "standing" class for those with an impairment that affects both legs, such as an above knee amputation or significant muscle weakness.
"I know no different, compared to someone who has had an accident and had to adapt to things. In my upbringing, I was treated like anyone else rather than any form of cotton-wool syndrome where parents can be overprotective.
"I was disciplined like any other kid, and had my work ethic and determination drilled into me by my parents."
Hall revels in the freedom his alpine pursuit provides.
"Up a mountain, nobody knows you've got a disability. You're just somebody out there skiing.
"There's no better feeling than the adrenaline flying down a mountain at 100km/h plus, living on the edge, or in slalom when you get to be aggressive and hit the poles."
Hall has been involved in the sport as a skier or a snowboarder since he was six. Snowboarding only became a Paralympic sport at Sochi so he pursued skiing 18 months from the Turin Games and went on to win gold in the slalom at Vancouver.
At PyeongChang he is looking to compete in up to five events with downhill, super G, super combined and giant slalom candidates to add to his slalom specialty.
Hall has welcomed the way the Paralympic movement has morphed into the mainstream.
"The amount of exposure from Rio meant people could see and follow Paralympic athletes more easily through technology and social media. Those out there with missing limbs, or in hospital after an accident, can aspire to do something which is a powerful force.
"That wasn't always the case. More in our communities are getting involved, and that inclusiveness can be life-changing."