The men's quad suffered the biggest upset when they finished fourth in a time of five minutes, 52.09 seconds.

Helen Casey and Jen Goldsack came fifth in the women's lightweight double while Paul Mattick and Daniel Harte were fourth in the lightweight group B semi.

The men's lightweight four and double both claimed fifth places.

The men's quad of Stephen Rowbotham, Matt Langridge, Matt Wells and Alan Campbell felt they had a realistic chance of becoming the first men's sculling boat since the seventies to win a medal at a World Championships.

They started well and kept up with pace-setters Slovenia and just after halfway they had edged past both Germany and Poland.

But the German crew raised the stroke rate and Britain could not respond after Poland took the lead from Slovenia.

Casey and Goldsack put themselves into contention through the middle 1,000m and although they edged out Russia for fifth place, they fell short of qualification.

"It was the best we could have done on the day - in fact I'm proud of our performance and determination," said Casey.

However, the defending British visually-impaired mixed coxed fours boat, easily booked their place in Saturday's final - winning the semi-final by 13 seconds.