The International Olympic Committee gave skiers a chance at these Games to compete in a discipline that snowboarders have made a significant part of the Olympics.
West became the inaugural winner, backing up his 2013 world championship in the event with a score of 92.00 that came in his first run of the finals. Each competitor gets two runs down the halfpipe during the final with the best of the two scores counting in the medal race.
Mike Riddle of Canada, world champion three years ago, finished second with a score of 90.60 in his second try. Kevin Rolland of France was third after being awarded 88.60 points in his first run.
Justin Dorey of Canada, expected to challenge for a medal, fell on both his runs after turning the best score in qualifying.
Snow fell steadily throughout the competition and the deeper it became at the bottom of the halfpipe the harder it was for the skiers to gain momentum as they made the transition into their next trick.
Three of the top four finishers had their best score in the first round.