Macartney celebrated his first international success at the 1998 Junior World Championships in Megève , France , when he finished third in the downhill race . From November 1999 he started in the World Cup . He took part in the 2002 Winter Olympics and was 25th in the downhill and 29th in the Super-G. At the 2006 Winter Olympics , he reached seventh place in the Super-G, 15th place in the downhill and 16th place in the super combined. In his two world championships in 2005 in Bormio and 2007 in Åre , a 28th place in the Super-G was his best result. He achieved the best World Cup result of his career on January 29, 2006, when he surprisingly finished second in the World Cup Super-G in Garmisch-Partenkirchen . A third place followed on December 15, 2007 in the descent on the Saslong in Val Gardena .
On January 19, 2008, Macartney had a serious fall on the downhill run on the Streif in Kitzbühel at a speed of 141.2 km / h and suffered a traumatic brain injury . He survived the fall without bone injuries and was able to leave the hospital for Salt Lake City after just three days . A year later Macartney fell again in Wengen and sustained an injury in his left knee; the American also had to end this season early. After the 2009/10 season, Macartney announced his retirement from ski racing.