With a 31-foot waterline, a 12-foot-1-inch beam, and 774 square feet of sail, the Southern Cross 39 has a voluminous hull and conservative proportions. Her design ratios describe a stable, balanced offshore cruiser rather than a light-air sprinter.
Design and Construction
Gillmer’s 39 carries the conservative, seakindly proportions of his earlier Southern Cross designs, but on a scale intended for serious passage-making. Her 36.55 percent ballast-to-displacement ratio and displacement-length ratio of 315 put her in the heavy-displacement category. A capsize screening figure of 1.8 and a comfort ratio of 35.2 further reinforce the picture of a boat built to carry crew and gear across oceans rather than win inshore races.
The hull is solid fiberglass, while the deck has a PVC foam core. The first 13 hulls were completed at the factory; subsequent boats were offered as kits for owners to finish. Some of those owner-completed yachts were later badged as Gilmer models to distinguish them from Ryder-finished boats.
Rig and Handling
The cutter rig carries 774 square feet of sail: a 332-square-foot mainsail and a 441-square-foot foresail. The rig dimensions are 50'10" for I and 17'4" for J.
A sail-area-to-displacement ratio of 16.33 is modest for a boat of this weight, consistent with a design focused on control and balance offshore rather than acceleration. Period assessments describe the Southern Cross 39 as a stable bluewater cruiser with balanced sailing performance, well suited to long-distance cruising.
The fin keel and skeg-hung rudder draw 5'4". That draft is a compromise intended to keep the boat manageable in anchorages while retaining the lateral plane needed for windward work.
Accommodations and Cruising Capacity
The 39-foot overall length and 12-foot-1-inch beam create a roomy interior for a boat of this era. The heavy-displacement hull and comfort ratio of 35.2 suggest a vessel planned for extended liveaboard use, with enough volume to stow provisions and gear for distant passages.
Tankage includes 120 gallons of water and 50 gallons of fuel. Those capacities, together with the boat’s displacement and interior volume, frame the Southern Cross 39 as a self-sufficient cruiser rather than a weekend coastal racer.
Propeller Arrangements and Known Issues
The best-documented mechanical change concerns the propeller installation. Early models featured a V-drive transmission with an exposed propeller. On later versions, the propeller was moved into an aperture in the rudder for better protection.
Buyers and owners should determine which arrangement a particular hull carries. The exposed propeller on early boats has less shielding from ground tackle and mooring debris than the later arrangement.
Production History and Ownership
The distinction between factory-built and kit-built boats is an important part of Southern Cross 39 ownership. The first 13 hulls left Ryder as complete boats; the remainder were supplied as kits, and some were later labeled Gilmer. This history matters for documentation and for the consistency of finish work below.
The later move to a rudder-aperture propeller is the principal factory-level refit lineage worth knowing. Because production ran throughout the 1980s, a used example may have either the early exposed-propeller specification or the later protected arrangement.
The Verdict
The Southern Cross 39 is a purposeful bluewater cruiser: heavy, stable, and quietly capable under her cutter rig, with the tankage and interior volume needed for long passages. For prospective owners, the two key considerations are the divide between factory- and owner-finished hulls and the change from the early exposed propeller to the later protected installation.
Pros
- Stable, heavy-displacement bluewater design with balanced performance
- Generous 120-gallon water and 50-gallon fuel capacities for distance cruising
- Lead ballast equal to 36.55 percent of displacement for offshore steadiness
- Later models gained the protection of a rudder-aperture propeller
Cons
- Early hulls carried an exposed propeller with less protection
- The modest sail-area-to-displacement ratio limits light-air pace
- Finish quality and documentation may vary because of the kit-built and owner-finished history
