In the wake of World War II, America’s lethargic general aviation market was ripe for an airplane that was fast, comfortable and above all, affordable. Walter H. Beech and his “Beech Boys” answered that call with the all-metal Model 35 “Bonanza.”
When the world’s bloodiest conflict ended in 1945, thousands of military pilots returned home and began flying for airlines, air taxi and flight schools. Civilian aviation was essentially banned during the war because of security concerns, the consumption of fuel and oil, as well as a critical need for war materiel. After suffering through more than three years of war, the American general aviation market exploded with demand for new aircraft. The market seemed unlimited, and sales of airplanes built by Piper, Taylorcraft, Aeronca and other airframe manufacturers skyrocketed.
Unfortunately, for airmen returning from the war-torn skies over the European and Pacific battlegrounds, so-called “new” airplanes were nothing more than warmed-over remakes of prewar models. Although reliable and well-designed for their time, these ships were saddled with technology stemming from the late 1920s. Their airframes were chiefly welded steel tubing covered with cotton fabric, and their wings were wood enveloped in doped cloth. There were a few exceptions, namely the Cessna 120 and 140 whose all-metal fuselages and metal wings (still covered in fabric) represented a step in the right direction. Cessna Aircraft Company, led by Dwane Wallace, recognized the need for an entirely new type of small airplane that would finally relegate the days of tube-and-fabric construction to history.
Wallace wanted to be ready for the postwar airplane boom, and late in the war put his engineers to work to design what he called “The Family Car of the Air.” Officially, the airplane was designated the P-370 but it failed to progress beyond the mockup stage and was cancelled in 1945. If the P-370 had made it to production, it was projected to have had a maximum speed of 165 mph, cruise speed of 140 and a landing speed of 50 mph.1
Other airframe manufacturers were looking to the future, including North American Aviation. The famed builder of the war’s best all-around fighter, the P-51 “Mustang,” introduced the “Navion,” a four-place, all-metal design powered by a 260-hp Lycoming engine. Equipped with a fighter-like sliding canopy and retractable landing gear, the Navion could cruise at 170 mph and land at 55. In 1947, California-based Ryan Aeronautical Company bought design and manufacturing rights to the Navion, and more than 1,000 were built from 1948-1950.
In Wichita, Kansas, the anticipated, postwar demand for a modern light airplane had not escaped the notice and attention of Walter H. Beech. As early 1943 the leader of Beech Aircraft Corporation had already realized that the days of the classic Beechcraft Model 17 Staggerwing cabin biplane would soon end. As a result, the company studied design of a four-place monoplane designated the Model 33. A wood fuselage mockup was completed, but the concept was shelved.2
During its heyday in the mid-to-late 1930s, the Model 17 had earned a reputation as the “Cadillac” of single-engine business aircraft and had no peer in terms of style, comfort and performance. Walter knew, however, that his beloved old biplane had an “Achilles heel” – cost. From its introduction in 1934, the Model 17 had been a hand-made machine that required thousands of man-hours to fabricate, assemble and complete.
Worst of all, perhaps, was the fact that a postwar version was projected to cost customers a stunning $29,000. Despite the “sticker shock,” in January 1946 the company established a production schedule for 50 Model G17S, but only 20 were eventually built because manufacturing costs proved prohibitive. Although a myth has arisen during the past 80 years that Walter Beech was firmly committed to the biplane, nothing could be farther from historical reality. Beech was committed to the future, not the past. He had learned to fly in a Curtiss JN-4 biplane in 1919, by 1926 he was quick to embrace the monoplane as the way of the future.
With the advent of aluminum alloy, stressed-skin airframe construction was pioneered and proven by designers such as Jack Northrop in the 1930s, Beech put engineer Theodore “Ted” Wells to work in 1935 with orders to design an all-metal, twin-engine Beechcraft. The prototype first flew in 1937 as the Model 18 and the “Twin Beech” went on to become a legend in its own time. More than 7,000 were built from 1937 to the end of production in 1969.
Mr. Beech knew that to compete in the highly competitive postwar market that was certain to occur, his company would need a “game changing” airplane. Amidst the pressure of war-time contracts and America’s relentless rush toward victory over Germany and Japan, he assigned chief engineer and vice president Wells to commence design studies for a four-place low-wing monoplane. Wells wisely put Ralph Harmon in charge of a group dedicated to bringing the project to fruition by 1945. Harmon, an experienced engineer who had made important contributions to the Beechcraft Model 28 gunship that became the U.S. Army’s XA-38 “Grizzly” in 1944, tapped fellow engineers Alex Odevseff, Noel Naidenoff, Jerry Gordon and Wilson Earhart to complete the team.
Gordon was the company’s expert on aerodynamics and would tackle design of the wings, and Earhart would design the wings’ internal structure. Odevseff was assigned responsibility for designing the fuselage while Naidenoff developed the fuel system and engine mount for the proposed Continental E-165 piston engine. As the airplane’s design evolved, Wayne Porter, an automotive stylist, joined the team. His job was to make the new Beechcraft attractive to the eye both inside and outside of the cabin.
Figuring into Walter Beech’s idea of exactly what a postwar airplane should be, J. Carlton Ward, president of the highly respected Fairchild Engine and Airplane Corporation, commented in 1944 that the “…postwar airplane, which recent consumer surveys indicate the public thinks should cost about $1,500-2,500 would, under present conditions, cost about $13,000. Standard equipment for such a ship, which could carry four or five passengers and their baggage in comfort equal to that of the automobile, but with 500-mile range and at a speed of 150 mph, would alone cost $12,500.” In addition, Ward refuted the assertion made by some analysts that postwar mass production of airplanes similar to that of the automotive industry was achievable. He cited figures showing that the American aircraft industry was capable of building only 10,000 per month at the height of the war. Considering such low numbers, he warned, “… it will therefore be seen that there is no mass production of airplanes comparable to that of the automobile industry.”
Walter Beech, however, was not interested in mass production. As Beechcraft Bonanza historian Larry Ball wrote in his classic book, “Those Incomparable Bonanzas,” Mr. Beech “had built his reputation by manufacturing swift, dependable airplanes with good comfort, range and payload” and Harmon’s team would be faced with maintaining that reputation. In addition, Walter Beech was equally adamant that a new, postwar Beechcraft excel in overall efficiency, therefore the team doubled their efforts to create an airplane with outstanding aerodynamics.3
Following months of study, discussion and postulating, it was decided that a single-engine, four-place, all-metal monoplane was the only plausible solution. Although competitors North American Aviation with its Navion and Republic Aviation with its four-place amphibian “SeaBee” were more than capable of designing and manufacturing airplanes, in 1945 neither company had experience selling their products in the general aviation marketplace. By contrast, Beech Aircraft Corporation had more than a decade of hard-won experience selling and supporting its products in that highly competitive arena – a distinct advantage that in the years ahead would play out in its favor.
Another and perhaps more formidable competitor than North American or Republic was the Piper Aircraft Corporation based in Lock Haven, Pennsylvania. In 1947, it was busy developing its own version of what a postwar Piper should be – the handsome, four-place PA-6 “Sky Sedan.” Powered by a 165-horsepower Continental engine, the PA-6 airframe was of mixed construction with aluminum alloy fuselage and fabric-covered wings. The airplane featured a retractable, conventional landing gear configuration, a maximum speed of 160 mph, a cruise speed of 140 and landed at a benign 49 mph. If the Sky Sedan had been certified and produced in quantity, it would have proven a worthy competitor to the new Beechcraft. William Piper could have beaten Walter Beech to the postwar market with an all-new design, but only two airplanes were built before the program was terminated in 1948 because of financial constraints.
Months into the design process it was decided that an opposed, four-cylinder engine was the best choice. Radial engines were never seriously considered and would have played havoc with aerodynamics because of the engine’s large frontal area. By contrast, inverted, in-line engines, either liquid-cooled or air-cooled, would benefit aerodynamics because of their narrow width, but the team rejected the incline powerplant as well.
A market research survey conducted by the company indicated that there would be sufficient demand for the new Beechcraft to justify development of an engine suitable for the design. Unfortunately, there were no engines that met all the team’s requirements. Choice of the engine was among the most critical aspects of the project and Harmon knew they had to get it right the first time. Letters were sent to Lycoming and Continental asking if they would consider developing an engine. Both companies responded in the affirmative. Two powerplants eventually became available—the six-cylinder Continental Motors E-165 and the four-cylinder Lycoming GO-290, both rated at 165 horsepower for takeoff. Because each engine met specifications, Harmon decided to test both designs.
Another important consideration was the landing gear. During the war, conventional gear configurations (tailwheels) still dominated both military and commercial aircraft, particularly fighters. There were, of course, some exceptions such as the Martin B-26 “Marauder” and the North American B-25 “Mitchell” medium bombers, as well as the Consolidated “Liberator” and Boeing B-29 “Superfortress” heavy bombers and the Bell P-39 “Aircobra” fighter, all of which featured a tricycle gear arrangement. After much debate and discussion, the team agreed that only a fully retractable, tricycle landing gear was acceptable.
The next consideration was the airfoil section and the wing itself. The engineers had experience with the National Advisory Committee for Aeronautics (NACA) 23000-series airfoil that had been used on the bullish and brutally powerful XA-38 “Grizzly” in 1944 and the venerable Model 18. The team also tested a laminar flow airfoil that offered less drag but would be more expensive to build. Wind tunnel tests showed that the NACA 23000 airfoil was the best choice for the airplane’s overall performance capabilities (in 1946 Beech Aircraft did flight test work with a laminar flow airfoil, but no further action was taken).
The next challenge was the empennage. Throughout the design process, the engineering team had made every effort to reduce drag, and a V-tail arrangement was favored over the conventional configuration. The reason for that choice centered not only on drag reduction and weight (two surfaces instead of three), but also because a V-tail could be located higher on the fuselage to avoid turbulent airflow coming off the wing. As early as 1943, the company had conducted wind tunnel tests of a V-tail and in 1944 installed an experimental assembly on a Model 26, AT-10 multi-engine trainer. The assembly featured a dihedral of 40 degrees and flight tests indicated that the V-tail was a promising design alternative.
Ralph Harmon and Jerry Gordon successfully campaigned for adoption of that configuration for the new monoplane, but the dihedral was reduced to 30 degrees. Extensive wind tunnel tests of a 1/5-scale model of the airplane showed that the V-tail was equal to a conventional empennage in terms of controllability, but produced less drag.
Throughout 1945 the team made slow but important progress, including an exhaustive stress analysis and fatigue testing program using two prototype airframes. These Beechcrafts would never take to the sky, yet they “flew” for a simulated 20,000 hours to prove the airplane’s robust airframe design and to ensure that no fatigue failures would occur during the certification flight test program. It is important to note that the fatigue tests were performed in addition to the normal static and fatigue tests mandated by the government’s Civil Aviation Authority.
By late 1945, Beech Aircraft Corporation’s ongoing effort to design and manufacture the most advanced four-place airplane in the world was nearing fruition. Five pre-production airplanes were built (including two for static/fatigue tests). One featured a laminar flow wing and was powered by Lycoming’s engine, and another was built with the NACA 23000 airfoil section and the Continental engine. Veteran Beechcraft test pilot Vern Carstens was chosen to fly the Lycoming-powered Beechcraft on its maiden flight. After performing thorough ground-based tests of the engine, fuel system, flight control rigging and subsystems, a series of taxi runs were completed on the factory’s paved runway that was oriented north-south in accordance with prevailing winds.
Those tests went smoothly, and on December 22, 1945, Carstens took the airplane aloft for a 40-minute evaluation. He found the airplane was about 10 mph faster than calculations had predicted, with a cruise speed of 175 mph. He cautiously probed the airplane’s low-speed flight characteristics with flaps and landing gear extended and retracted, investigated control response in pitch, roll and yaw, as well as determining stall characteristics. He was impressed with the ship’s overall behavior, and after landing declared to Walter Beech, “It’s the best airplane we’ve built yet!”4
The second flight-test prototype, equipped with the Continental E-165 and NACA 23000 airfoil, flew soon after the first airplane. A comparison of the two found that both airplanes were capable of cruising at 175 mph. In the wake of further tests, the NACA airfoil was chosen for production airplanes because it was easier and less costly to build. During 1945, the certification program continued to advance, but one of the pre-production airplanes was destroyed and the pilot killed when the V-tail separated from the fuselage (the observer bailed out and reported what happened). The accident occurred during high-speed dive tests aimed at determining maximum dive airspeed when balance weights on the empennage separated from the control surfaces, inducing flutter. Deeply grieved at the loss of the pilot, Harmon’s team pushed forward and implemented design changes to the empennage that resolved the problem.
To ensure that the airframe, engine, propeller, landing gear, flap systems and their components were ready for production and certification, Walter Beech ordered what today is known as “Function and Reliability” flights using three airplanes. The Beechcrafts were flown day and night in all weather conditions (except icing) along a 170-mile course that included 10 airports. Pilots eventually accumulated up to 600 hours on each of the airplanes, making a minimum of three takeoffs and landings per hour. The flights served their purpose, revealing minor problems affecting landing gear and flap motor operation as well as reliability issues with a few other components, all of which were quickly resolved.
As the certification program drew to a close, and before final specifications were released to Beechcraft dealers worldwide, Beech Aircraft Corporation received orders (with cash deposits) for 500 airplanes. When specifications were released, the orders swelled to 1,500 airplanes! Finally, on March 25, 1947, the CAA issued Approved Type Certificate A777 for the Model 35 Bonanza, paving the way for series production to begin. Initially, the factory manufactured 12 airplanes per day during 1947. Production slowly accelerated and by the end of 1948, 1,500 Bonanzas had rolled off the assembly line and into the hands of new owners.
As for the competition, the Republic’s SeaBee amphibian soon failed, the victim of steadily rising production costs that forced an end to the program. Only the Navion posed any serious threat to the Bonanza’s rapid dominance of the high-performance, four-place small airplane market. The Navion’s level of high performance fell short of that of the new Beechcraft. Despite adding more and more horsepower to the airframe, the Navion was consistently 25 mph slower than the Bonanza.5
In 1949, the A35 Bonanza made its debut and was the first Model 35 to incorporate a sheet metal spar carrythrough that replaced the tubular steel unit used in early production airplanes. It was the first Bonanza to be licensed in the Utility Category at a maximum gross weight of 2,650 pounds. Beechcraft workers built 71 A35s before introduction of the improved B35 for the 1950 sales year. It featured a Continental E-185-8 engine that developed 196 horsepower for one minute (at 2,450 RPM), and engines installed in the C35, D35 and E35 versions produced from 1950 through 1952 featured more horsepower, the chord of the V-tail was increased by 20 percent and dihedral angle increased to 33 degrees. As the years went by, the Bonanza continued to evolve through the F35, N35, P35, S35 and finally, the V35.
Introduced in 1966, the V35 was powered by a Continental IO-520-B engine rated at 285 horsepower and could attain a maximum speed of 210 mph (sea level). Maximum gross weight was 3,400 pounds – an increase of more than 800 pounds since the Model 35 of 1947. Both the V35 and V35A (introduced in 1968) boasted a one-piece “Speed Sweep” windshield that replaced the two-piece unit of the S35. All Model 35 Bonanzas manufactured in 1968 and after were reclassified with the prefix “V” to separate those airplanes from the Model 33 “Debonair,” which was renamed “Bonanza.”
Production of the iconic Model 35 came to an end in November 1982 when V35B serial number D-10,403 was delivered to the production flight test department. It was delivered to a dealer in May 1984. The last Model 35 to be delivered to a retail customer, V35B serial number D-10,399 occurred in August 1984.
Regardless of how it is measured, whether by comfort, quality of manufacture, speed or utility, the Beechcraft Model 35 has never had an equal and is remembered as one of general aviation’s most significant designs. It was, and remains to this day, incomparable.
Notes:
1. Phillips, Edward H.: “Piper – A Legend Aloft;” Flying Books International, Publishers & Wholesalers; Eagan, Minnesota; 1993.
2. Phillips, Edward H.: “The Staggerwing Story;” Flying Books International, Publishers & Wholesalers; Eagan, Minnesota; 1996.
3. Ball, Larry; “Those Incomparable Bonanzas;” McCormick-Armstrong Co., Inc., Publishing Division; Wichita, Kansas; 1971
4. Ibid
5. Ibid
6. Phillips, Edward H.: “Beechcraft – Pursuit of Perfection;” Flying Books, Publishers and Wholesalers; Eagan, Minnesota; 1992.
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