Norwegian ski jumper Kristoffer Eriksen Sundal can count himself lucky after a shocking incident at the top of the large hill at the FIS Ski Jumping World Cup opener in Lillehammer.

Sundal, 23, was preparing to set off for his qualification jump at the top of the almost 100-metre long, steep ramp at the historic Lysgårdsbakkene Hoppanlegg ski jump.

Jumpers slide across onto a bench before being given the signal it is safe to start their run, reaching speeds of up to 90km/h.

Sundal was not given that opportunity though, with video footage from FIS TV showing Sundal mid-way through adjusting his gloves and goggles before being hit from behind by an advertising hording, as officials frantically shouted behind him.

Despite being unprepared to embark down the precipitous slope, Sundal still managed to compose himself and complete his leap safely, even taking the lead in qualification with a distance of 134.5 metres.

"This is a scandal," NRK commentator Christian Nilssen said on Norwegian TV.

"This could have gone really crazy in many ways," ​​two-time ski flying world record holder Johan Remen Evensen added.

Sundal, understandably, was furious when he reached the bottom of the slope, throwing up his hands after landing safely.

"I have to jump again? Damn it, is it possible? It is life threatening," he was recorded as saying by Norwegian broadcaster NRK.

"If I had had my arm between the beam and the advertising board, my body would have been pushed off and I would have got stuck, so a joint or a shoulder would probably have been broken.

"It's fortunate that it went well."

Eurosport commentators were also stunned by the incident, with former jumper Werner Schuster describing the situation as life threatening in commentary.

National team coach Magnus Brevig praised Sundal's quick recovery.

"It was very frightening and scary, but extremely well handled by Sundal," Brevig told NRK. 

"He is tough."

Event organiser Terje Lund said it was too early to determine the cause of the incident, and that a full investigation would take place.

"This type of incident should not happen," he told NRK.

"Most likely it is a small human error. But there will be speculation, we have to get some time to look at it."

Sundal, who went on to finish seventh overall, said he received an apology from the organiser.

"They were very upset," he said. 

"I understand that, but they don't need to be so upset. Despite everything, it went well. I got to jump and I'm happy with it."

Incidents at the top of ski jumps are incredibly rare, but not unheard of.

Bjørn Einar Romøren was preparing to leap in an event in Predazzo in northern Italy in 2008 when a steward slid down the slope behind him and took his legs away, leaving the Norwegian desperately hanging on to the bench.