Though the mainsheet is your throttle when sailing to windward the C Scow traveler (rear of the boat) can be used to position the boom for different wind conditions.
The traveler controls are located on most boats as dual controls to be operated on either tack. Actual location varies by boat, but they are easily accessible by either the skipper or crew.
In very light wind (0-4) the traveler can be anywhere from 6" to 12" off center. The traveler is normally set closer to the centerline in flat water and more outboard in waves.
In medium air (6-12) the best position in 12-15" off center. As the boat becomes overpowered with some cunningham and vang tension already on the traveler is set out to the edge of the boat. However, be sure to pull it back in to the 12-15" position in the lulls to point high.
The C Scow was the first class of scow built by Harry C. Melges, Sr. in 1945; it quickly became an all-time speed favorite. The C Scow has come a long way from the days of wooden materials and cotton sails. It continues to be a very revolutionary sailboat, inspired by more than 100 years of competitive racing. This cat-rigged, maneuverable sailboat is great fun and a total pleasure to sail..... Very Fast, Fun, and Furious!