The Designer's Vision
Robert Nesmith developed the Cougar in Houston, Texas, during the mid-1950s with the ambitious goal of improving upon Steve Wittman's successful Tailwind design. Where the Tailwind used an 85-horsepower engine, Nesmith specified a more powerful 118-horsepower Lycoming O-235, while maintaining similar overall dimensions and the proven NACA 4309 airfoil across 83 square feet of wing area. The name "Cougar" came from the University of Houston mascot, reflecting Nesmith's local connections and his daughter's college affiliation.
Nesmith's approach differed markedly from traditional aircraft manufacturers. Rather than establishing a production line, he marketed detailed construction plans directly to amateur builders, positioning the Cougar as an affordable entry into sport aviation. He even incorporated the aircraft into programs for troubled youth, using the collaborative building process to teach teamwork and technical skills.
Construction and Performance
The Cougar's design philosophy emphasized simplicity without sacrificing performance. The aircraft featured a two-spar wooden wing covered with plywood and fabric, mated to a steel tube fuselage also covered in fabric. This mixed-construction approach kept costs reasonable while providing excellent strength-to-weight characteristics. The standard configuration included fixed tailwheel landing gear, though some builders later opted for tricycle arrangements.
With its 115-horsepower Lycoming O-235 engine, the Cougar demonstrated remarkable performance figures for its era. The aircraft achieved a maximum speed of 195 mph and cruised at 166 mph, with an economical cruise option of 135 mph. The design's 53-mph stall speed and impressive climb rate of 1,300 feet per minute made it both fast and forgiving. Range extended to 750 miles on 25 gallons of fuel, while the service ceiling reached 13,000 feet.
Evolution and Recognition
The Cougar gained significant recognition when a modified version created by Leonard Eaves won third place in a 1963 Experimental Aircraft Association design competition. Eaves' innovation centered on folding wings, which enhanced the aircraft's practicality for homebuilders with limited hangar space. Following this success, the EAA took over plan distribution from Nesmith, later transferring rights to Acro Sport.
Several variants emerged from the basic design, including the Cougar Comet powered by a 125-horsepower Lycoming O-290D engine. Builders experimented with power plants ranging from the 85-horsepower Continental C85 up to 150-horsepower Lycoming O-320 engines, with the higher-powered versions delivering even more impressive performance.
Global Reach
While precise construction numbers remain unknown, sources indicate that hundreds of Cougars were completed by amateur builders. Most construction occurred in the United States, though the design reached international builders as well. Notable examples include N1353N (serial J-1) completed in 1958, N1692 (serial B-001) from 1968, and N14470 (serial FRL1).
New Zealand builder Jerry Chisum demonstrated the design's enduring appeal when he first flew ZK-CNA2 on July 24, 2013. This aircraft, constructed between 1993 and 2013, changed hands several times among New Zealand aviators, with Rod Davis owning it from 2013 to 2015, Peter J. Locke from 2015 to 2020, and P.J. Gotlieb acquiring it in January 2020.
Technical Specifications
The Cougar measured 18 feet 11 inches in length with its 20-foot 6-inch wingspan, creating a compact yet roomy cabin for two occupants seated side by side. Empty weight of 624 pounds and maximum gross weight of 1,250 pounds provided a useful load of 626 pounds, sufficient for two adults and baggage for extended cross-country flights. The aircraft's impressive power-to-weight ratio contributed to its exceptional takeoff performance, requiring only 450 feet for departure and 350 feet for landing.
Legacy and Influence
The Nesmith Cougar's influence extended well beyond its own production numbers, inspiring numerous derivative designs including the Chigger and Skydoll variants that incorporated folding wing features. The aircraft proved that amateur builders could construct sophisticated, high-performance aircraft using relatively simple techniques and readily available materials.
Today, examples like ZK-CNA2 continue flying, demonstrating the soundness of Nesmith's original design philosophy. The Cougar earned its place in homebuilt aviation history as proof that thoughtful engineering could deliver professional-level performance from amateur construction methods, paving the way for the modern experimental aircraft movement.