Ainslie has won Olympic medals in both Finn and Laser classes
Great Britain's medal hopes must wait to continue their quest after all sailing was cancelled on Thursday due to lack of winds and poor visibility.
Double gold medallist Ben Ainslie (Finn) and the first-placed Yngling crew of Sarah Ayton, Sarah Webb and Pippa Wilson were affected.
Officials said reserve days would be used for some classes, but organisers must now deal with a large backlog.
Four races were lost on Wednesday, to go with the 15 cancelled on Thursday.
Racing was due to start at 0600 BST in the 49er, 470, Laser, Laser Radial, windsurfing, Finn and Yngling classes on Thursday but was called off because winds were so light that they barely stirred flags and banners at the Qingdao sailing venue, 500km south of Beijing.
Organisers said reserve days would be used to complete the opening series of races, of which there are 10 in all classes except the 15-race 49er class.
A medal race showdown will then take place between the top 10 competitors with the lowest score in each class, with finishing positions in the final race counting for double points which are added onto the total.
The Finn and Yngling classes have completed seven races and will come out again on Friday - originally planned as a reserve day for both fleets - when winds are forecast to pick up for better sailing conditions.
On Wednesday, attempts to start the day's second races for the Finn, Yngling, Laser and Laser Radial classes were dropped due to light winds.
Thursday respresents the first full day of racing lost due to wind conditions.