Alpensia Ski Jumping Centre, Oct 30, 2017 : Alpensia Ski Jumping Centre in Alpensia Olympic Park of the 2018 PyeongChang Winter Olympics is seen in PyeongChang, east of Seoul, South Korea. The 23rd Winter Olympics will be held for 17 days from February 9 - 25, 2018. The opening and closing ceremonies and most snow sports will take place in PyeongChang county. Jeongseon county will host Alpine speed events and ice sports will be held in the coast city of Gangneung. (Photo by Lee Jae-Won/AFLO) (SOUTH KOREA)

Alpensia Ski Jumping Centre, Oct 30, 2017 : Alpensia Ski Jumping Centre in Alpensia Olympic Park of the 2018 PyeongChang Winter Olympics is seen in PyeongChang, east of Seoul, South Korea. The 23rd Winter Olympics will be held for 17 days from February 9 - 25, 2018. The opening and closing ceremonies and most snow sports will take place in PyeongChang county. Jeongseon county will host Alpine speed events and ice sports will be held in the coast city of Gangneung. (Photo by Lee Jae-Won/AFLO) (SOUTH KOREA)

Alpensia Ski Jumping Centre, Oct 30, 2017 : Alpensia Ski Jumping Centre in Alpensia Olympic Park of the 2018 PyeongChang Winter Olympics is seen in PyeongChang, east of Seoul, South Korea. The 23rd Winter Olympics will be held for 17 days from February 9 - 25, 2018. The opening and closing ceremonies and most snow sports will take place in PyeongChang county. Jeongseon county will host Alpine speed events and ice sports will be held in the coast city of Gangneung. (Photo by Lee Jae-Won/AFLO) (SOUTH KOREA)

In this Monday, Oct. 30, 2017, photo, the Alpensia Ski Jumping Centre in Pyeongchang, South Korea. South Korea's sleepy skiing destination of Pyeongchang is finally looking like a Winter Olympics host city after more than a decade of work, two failed bids, and chapters of controversy over venue locations, construction delays and costs. (AP Photo/Ahn Young-joon)

In this Monday, Oct. 30, 2017, photo, the Alpensia Ski Jumping Centre is being prepared in Pyeongchang, South Korea. South Korea's sleepy skiing destination of Pyeongchang is finally looking like a Winter Olympics host city after more than a decade of work, two failed bids, and chapters of controversy over venue locations, construction delays and costs. (AP Photo/Ahn Young-joon)

(FILES) This file photo taken on October 30, 2017 shows a general view of the ski jumping venue of the Pyeongchang 2018 Winter Olympic games, at the Alpensia resort in Pyeongchang. South Korea is ready to welcome the world at the 2018 Winter Olympics, including athletes from its sabre-rattling neighbour North Korea, chief organiser Lee Hee-Beom said in Prague on November 3, 2017. / AFP PHOTO / Ed JONES

, FEBRUARY 16, 2016 : at Alpensia Ski Jumping Centre, in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 16, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view, FEBRUARY 16, 2016 : at Alpensia Ski Jumping Centre in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view, FEBRUARY 16, 2017 - Ski Jumping : FIS Ski Jumping World Cup Women's Individual Normal Hill at Alpensia Ski Jumping Centre, PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view, FEBRUARY 16, 2017 - Ski Jumping : FIS Ski Jumping World Cup Women's Individual Normal Hill at Alpensia Ski Jumping Centre, PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 15, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 15, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 15, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 15, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 15, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view, FEBRUARY 15, 2017 - Ski Jumping : FIS Ski Jumping World Cup Women's Individual Normal Hill at Alpensia Ski Jumping Centre, PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

General view of Alpensia Ski Jumping Centre, FEBRUARY 13, 2016 : in PyeongChang, South Korea. (Photo by YUTAKA/AFLO SPORT)

This photo taken February 3, 2017 shows a general view of the Alpensia Ski Jumping Centre, a venue for the upcoming Pyeongchang 2018 Winter Olympic Games, in Pyeongchang. / AFP PHOTO / JUNG Yeon-Je

Ryan Stassel of the US jumps during a training session for the FIS Snowboard World Cup Big Air event at Alpensia Ski Jumping Centre in Pyeongchang, 150 km east of Seoul on November 25, 2016. The World Cup Big Air event is a test event for the upcoming PyeongChang 2018 Winter Olympic Games. / AFP PHOTO / JUNG YEON-JE