Design Evolution and Innovation
Stan McLeod, a former Royal Canadian Air Force pilot, developed the SA-105 Super Cavalier as the most advanced variant in his series of homebuilt aircraft derived from Yves Gardan's French GY-20 Minicab. McLeod extensively modified the original 1949 French design, creating a fuselage four inches wider, four inches taller, and seven inches longer to accommodate North American builders' preferences for more powerful engines and higher performance.
The SA-105 incorporated several groundbreaking safety innovations for homebuilt aircraft of its era. McLeod relocated fuel storage from the cockpit area to wingtip tanks, significantly improving crashworthiness while providing the additional benefit of increased wing aspect ratio and lift generation. The aircraft featured a sophisticated "rod nose gear" tricycle undercarriage system with retractable landing gear, representing a significant advance over the simpler fixed-gear variants in the Cavalier family.
Technical Specifications and Performance
The Super Cavalier's all-wood construction supported engines ranging from 100 to 200 horsepower, including the popular Lycoming O-290 producing 125-135 horsepower, Continental O-200, and Franklin 4AC engines. With its NACA 23115 root airfoil transitioning to NACA 23010 at the tips, the aircraft achieved a maximum speed of 200 mph and cruised at 120-150 mph. The design's 117 square feet of wing area and 1,850-pound gross weight resulted in a wing loading of 12.7 pounds per square foot.
Fuel capacity totaled 56 gallons when equipped with optional wingtip tanks—34 gallons in the main system plus 22 gallons in the tip tanks. This configuration provided excellent range capabilities while maintaining the aircraft's clean aerodynamic lines. The cockpit featured an upward-hinging canopy and accommodated two occupants side-by-side, with some early models offering an optional third jump seat.
Manufacturing and Market Reception
K & S Aircraft Supply, operated by Kay and Stan McLeod in Calgary, Alberta, marketed the SA-105 plans beginning around 1968 as part of their broader Cavalier series development program. The company had already achieved significant success with the simpler SA102.5 variant, selling over 1,200 sets of plans by 1976. However, the SA-105's complexity, particularly its retractable landing gear system, limited its appeal among amateur constructors.
Only a handful of SA-105 Super Cavaliers were completed compared to the dozens of SA102.5 aircraft that reached flying status. The retractable gear mechanism required significantly more fabrication skill and time investment than most homebuilders were prepared to undertake, despite the performance advantages it offered.
Company History and Legacy
K & S Aircraft Supply underwent several corporate transformations during the Cavalier series' production run. The company was renamed Macfam in 1979, then became McAsco in 1984 before transferring operations to the United States as MacFam. Plans for the Cavalier series are no longer available, and the company has ceased operations under all its various names.
Stan McLeod's design philosophy emphasized creating fast, simple, and efficient aircraft that amateur builders could construct using readily available materials and techniques. His innovations in tricycle landing gear configuration and fuel system safety influenced subsequent homebuilt designs throughout the 1970s and 1980s.
Current Status and Cultural Impact
The SA-105 Super Cavalier's legacy lies primarily in its advancement of homebuilt aviation technology rather than in large numbers of completed aircraft. The design demonstrated that amateur constructors could achieve performance rivaling production aircraft through careful engineering and innovative construction techniques. McLeod's emphasis on safety features like relocated fuel tanks and robust landing gear systems established new standards for homebuilt aircraft design.
While exact numbers of airworthy SA-105 aircraft remain unknown, the broader Cavalier series contributed significantly to the growth of experimental aviation in North America. The design's influence can be seen in later homebuilt aircraft that adopted similar safety innovations and performance-oriented design philosophies. The few completed SA-105 examples represent ambitious projects by skilled builders who sought maximum performance from wood construction techniques, achieving the goal of 200-mph capability that McLeod envisioned for serious amateur constructors.