Coleraine rowers Richard Chambers, brother Peter and Alan Campbell progressed at Eton Dorney on Tuesday.
The Chambers brother are through to the lightweight fours final after winning their semi-final in 5:59.68.
The British crew eased through to lead after 1500m and they are the fastest qualifiers for Thursday's final.
Campbell put in another impressive display in winning his single sculls quarter-final, leading from the start and clocking a time of 6:52.10.
The 29-year-old, who beat German rival Marcel Hacker into second, will race again in the semi-finals on Wednesday.
Campbell showed a return to form in the heats, taking victory on Saturday in 6:47.62.
Richard and Peter Chambers will start as gold medal favourites after another stylish performance.
The quartet, which also includes Rob Williams and Chris Bartley, were also fastest in Saturday's heats, clocking 5:49.29 over the 2000 metres.
They have finished on the podium in each of the three World Cup events this season and took victory at the most recent regatta in Munich.