The “Baby Beechcraft” – Part Two

Beech Aircraft Corporation’s Model 76 “Duchess” and the Model 77 “Skipper” were welcome additions to the company’s product line, but the economic recession of 1981 clipped their wings

During the three-day Beechcraft International Sales Roundup held in November 1975, two proposed aircraft were revealed to more than 800 Masters of Aircraft Salesmanship attending the event. The first to be unveiled was the PD 289, a preliminary design aimed at the four-place, lightweight twin-engine segment of the market, and PD 285, a single-engine, two-place airplane aimed at training fledgling student pilots how to fly.¹

Both Beechcrafts were intended to fill gaps in the company’s entry-level product line that had been occupied since 1963 by the successful Model 23 Musketeer/Sundowner and Model 24 Sierra series airplanes. As with their older brethren, the new airplanes would augment the lineup of Beechcraft products at the company’s popular Beech Aero Centers, but would also compete with the new Piper PA-44 Seminole, Cessna Model 303 and the Grumman American GA-7 Cougar – all aimed at the same lightweight, multi-engine trainer market as the Model 76.

The PD 289 would be powered by two Avco Lycoming, four-cylinder piston engines, each rated at 180 horsepower and fitted with counter-rotating propellers. An early proof-of-concept prototype had begun flight testing in September 1974 that continued into 1975, providing Beech engineers with a wealth of flight-test data about the design’s aerodynamics, performance with one-engine inoperative, airframe and engine systems and overall flight characteristics. A year later at the 1976 sales extravaganza, company officials introduced the former PD 289 as the Model 76 Duchess. The name had been chosen after a contest involving hundreds of Beechcraft franchise employees. Of these, 25 had submitted the name “Duchess” and each person was awarded $250 for their suggestions.²

The Duchess would be built at the company’s facilities in Liberal, Kansas, alongside the Model C23 and C24 single-engine Beechcrafts. The first production Duchess flew on May 24, 1977, with veteran Beech engineering test pilot Vaughn Gregg at the controls. FAA certification was achieved on January 24, 1978, with approval for day and night VFR/IFR flight operations in the Normal Category. Beechcrafters rolled out the first Duchess for delivery in May 1978, and many of the initial production airplanes were flown to Beech Aero Centers to train aspiring multi-engine pilots.

The Model 76’s aluminum alloy, semi-monocoque fuselage and full-cantilever wing used the same bonded honeycomb sandwich technology as the Model 23/24 series. The wing featured the NACA-developed 63₂A415 airfoil section with dihedral set at slightly more than six degrees, while the angle of incidence varied from three degrees at the wing root to zero degrees at the wingtip. Frise-type ailerons were installed along with single-slot trailing edge flaps that were electrically operated. Wingspan was 38 feet with a total area of 181 square feet, including ailerons, and wing loading was 21.5 pounds per square foot. The empennage featured a tall vertical stabilizer topped by a horizontal stabilizer with conventional elevator/rudder, each surface equipped with a trim tab.³

The main landing gear was a rugged, but practical, trailing beam design that retracted inward into wheel wells, while the nose gear retracted upward and forward into the lower nose section. All three gear were extended/retracted using an electro-hydraulic system similar to that of the Model C24 Sierra 200. The main gear featured a generous track of 10 feet six inches that, in concert with the steerable nose gear, made the Duchess easy to maneuver on the ground. A separate hydraulic system was installed to supply fluid for disc brakes on the main gear.

Typical empty weight (varied depending on equipment options) was 2,446 pounds, increasing to a maximum takeoff weight of 3,900 pounds. The Duchess could takeoff (sea level/standard day) in 1,017 feet. Maximum ramp weight was 3,916 pounds with a zero fuel weight of 3,500 pounds. Standard fuel capacity was provided by a single tank in each wing for a total of 100 useable gallons. Useful load for a standard-equipped airplane was 1,470 pounds.

The two Avco Lycoming air-cooled, O-360-A1G6D four-cylinder, opposed piston engines were each rated at 180 horsepower and were fitted with carburetors, not fuel injection, to reduce costs. The Hartzell two-blade, constant-speed propeller on the left engine rotated clockwise, while the right engine’s propeller rotated counter-clockwise. That arrangement essentially eliminated the long-standing “critical engine” scenario and eased pilot workload with one engine inoperative.

In terms of performance, the Model 76 compared favorably with its single-engine senior, the six-place Beechcraft Model A36 Bonanza, and was inserted into the Beechcraft product line between the A36 and the Model 58 Baron. A sampling of approved airspeeds associated with flying the Duchess include:

•  Vne (never exceed airspeed): 194 KIAS
•  Maximum speed: 171 KIAS
•  Maximum cruising speed, 6,000 feet altitude: 166 KIAS
•  Stall speed, power at idle RPM, flaps fully extended: 60 KIAS

The Duchess had an excellent, two-engine rate of climb at sea level of 1,248 feet per minute, but decreased to only 235 feet per minute at maximum gross weight with one-engine inoperative. Service ceiling 19,650 feet with both engine operating, falling to 6,170 feet with one engine inoperative.

Beech Aircraft marketing and management officials considered offering a turbocharged version of the Duchess (unofficially designated the Model 76TC). One airplane was modified by installation of two Avco Lycoming TO-360 turbocharged engines that required modification of the cowlings to accept the turbocharger installation. First flight occurred on January 31, 1979, piloted by Vaughn Gregg who was accompanied by flight test engineer Bryan Mee. The Model 76TC made 43 flights and accumulated 34.4 hours in the air before the project was cancelled. The final flight occurred on July 10, 1979.⁴

Initial orders for Duchess were strong, with 72 aircraft built in the first year of production followed in 1979 by 213. Production continued at a slower pace during the next few years until 1982 when production was terminated because of tough market conditions. A total of 437 Model 76 were built, and as of 2016, many are still flying with private owners and flight schools both in the United States and internationally. Prices vary from about $65,000 for a well-equipped airplane to as much as $150,000 for an exceptional example that has been meticulously maintained and has accumulated only 5,000-8,000 hours total time on the airframe.

The company’s other new airplane, the two-place Model 77 Skipper, began life in 1974 as the PD 285 and was intended primarily as an entry-level trainer to be operated by Beech Aero Centers. Originally, the PD 285 was to be powered by a Teledyne Continental four-cylinder, air-cooled, opposed piston engine rated at 100 horsepower, and the engineering proof-of-concept airplane first flew from Beech Field on February 6, 1975, with a conventional empennage design.

As flight testing progressed, however, the flight test airframe was rebuilt with a T-tail empennage, and the Continental powerplant was replaced by an Avco Lycoming, four-cylinder O-235-L2C engine rated at 115 horsepower. The chief reasons for the T-tail stemmed from engineering’s desire that the airplane to possess good pitch control at low airspeeds, as well as excellent recovery from intentional spins. The latter was important because the Skipper was approved for intentional spins (up to six turns) and, in the author’s opinion, was an excellent airplane with which to introduce pilots to intentional spins, and more importantly, how to recover safely (see page 25).

First flight of a pre-production airplane occurred on September 12, 1978, under the control of Vaughn Gregg. The FAA certified the Model 77 in April 1979 and plans called for initial deliveries to begin from the factory in Liberal, Kansas, in May. Beech Aircraft officials had this to say about the new Skipper: “A totally new aircraft combining the best fruits of NASA research and Beechcraft’s long experience, the Model 77 incorporates the T-tail first used so successfully on the Beechcraft Super King Air, and a new GAW-1 wing section originated by NASA following their high-speed, supercritical airfoil studies [the wing was particularly designed for low-speed flight and was well suited to a primary trainer such as the Skipper]. The airplane’s spacious, two-place cabin affords a full 360-degrees of visibility … and left and right cabin doors [provide] convenient access.”⁵ Soon after the announcement that the Model 77 would enter production, orders came in from Beech Aero Centers worldwide for a few hundred of the new Beechcraft. The Skipper began equipping Beech Aero Centers in 1979 when 47 airplanes were manufactured.

General specifications for the Model 77 include:

•  Full-cantilever wing using the GAW-1 airfoil featuring a dihedral of six degrees at the root; wingspan 30 feet, total area 129.8 square feet.
•  Wet-wing cells held a total of 29 gallons of useable fuel.
•  Tubular spar fabricated from aluminum alloy sheet combined with fiberglass-based adhesive to ensure bonding along all stations of the wing.
•  Ribs bonded to aluminum ally ribs.
•  Ailerons stiffened by heavy beading across the span.
•  Electrically-operated flaps, also heavily beaded for stiffness.
•  All primary flight controls and flaps were actuated by torque tubes instead of cables under tension.
•  Lower fuselage structure was bonded together, then built up using aluminum alloy, semi-monocoque construction.
•  The cantilever T-tail empennage featured a horizontal stabilizer with trim tabs on each elevator panel and the rudder.

The fixed main landing gear was set at a track of 8 feet 3.5 inches and used tubular springs for shock absorption, while the steerable, self-centering nose gear incorporated an air-oil shock absorber and shimmy damper. Toe-operated brakes were standard equipment. The Model 77 was a relatively small airplane – total length from propeller spinner to tail was 24 feet 1.5 inches, height 6 feet 11 inches, and the T-tail spanned 9 feet 10 inches. The Avco Lycoming O-235 engine was a good choice for the trainer and had already earned an excellent reputation for reliability and low operating costs, despite some problems with spark plug fouling caused by 100LL avgas that had come into use by the late 1970s. A Sensenich fixed-pitch, aluminum alloy propeller was standard equipment.

Performance was nominal for a primary trainer. Maximum speed (sea level) was 106 knots and cruising speed was only 105 knots at a power setting of 80 percent. With flaps fully extended, the Model 77 stalled at 47 CAS (calibrated airspeed). Maximum rate of climb was 720 feet per minute and service ceiling was 12,900 feet. Loaded with full fuel (29 gallons useable) and flying at an altitude of 4,500 feet at maximum cruising speed, the Skipper had a range of 327 nautical miles (nm), increasing to 413 nm at 51 percent power setting.⁶

By 1981, demand for the Model 77 began slipping away as the nation prepared to weather an economic recession that would eventually lead to a severe downturn for the general aviation industry. Production continued at the Liberal factory through 1980 at a rate of about 10 airplanes per month when 140 Skippers were manufactured. That number declined to 125 in 1981 when Beech Aircraft Management terminated production after 312 of the trainers had been built.⁷

As of early 2016, a large number of Skippers remain active with flight schools, but many have been purchased by private owners who fly them for fun and on short air tours in the United States, England and Western Europe. Prices average between $15,000-$25,000, depending on total time on the airframe, engine and equipment.

Flying the Beechcraft Skipper

Beginning in 1979, the Beech Flying Club operated the Skipper alongside the Model C23 Sundowner for training student pilots. The Skipper’s cabin was spacious compared to that of a Cessna 150/152 (which I had flown for years) and about equal to that of the Piper Tomahawk. Visibility outside from the cockpit was excellent, and the large doors made entry and exit easy. The instrument panel was well laid out, and the centrally-located power quadrant housed the throttle, mixture and carburetor heat controls.

The wide main landing gear track, coupled with the steerable nose gear, facilitated learning how to maneuver the airplane on the ground, and the brakes were more than adequate for the flight training task. Although the Model 77 had a maximum gross weight of only 1,650 pounds, I often wished the Avco Lycoming O-235 engine had another 35 horsepower, particularly on hot summer days in Kansas.

I usually flew one-hour training sorties with fuel tanks half full to help performance, but the airplane’s rate of climb was always marginal with two people on board, often managing no more than 100-150 feet per minute (fortunately, that part of Kansas was flat!). Once airborne, however, the Skipper flew well. The student usually mastered shallow and steep turns quickly, followed by slow flight and introduction to stalls. For these maneuvers the Skipper was a superb flight training platform, but once again, I wished it had more horsepower. Climbs to higher altitudes were a slow process. That unfortunate characteristic became more evident when it came time to give the student optional spin recovery training.

The usual scenario went like this: After a thorough ground school session discussing spin entry in the Skipper and the salient points of spin recovery, we donned backpack parachutes and took off, climbing to a minimum of 6,000 feet (8,000 was preferred, for safety’s sake). After advising local ATC of our intention to conduct multiple spins in the practice area, I demonstrated how to make the Skipper spin:

•  Power to idle.
•  Maintain altitude.
•  At the stall break, hold the control wheel full aft, wings level, being careful not to release back pressure.
•  Apply full left rudder.
•  When the airplane reluctantly rolled left, apply full right aileron to induce a cross-control stall.
•  The Skipper would roll sharply into the incipient spin, but only if the flight controls were held in position.

The spin stabilized nicely after the second turn. Rotation was rapid, and I normally allowed up to five or six turns before initiating recovery. The next steps happened in fast succession to terminate the spin:

•  Full opposite rudder to stop rotation.
•  Apply brisk forward pressure to the control wheel to break the stall.
•  When rotation stopped and the wings were flying again, maintain wings level and slowly apply back pressure to resume straight and level flight, being careful not to exceed airspeed limitations.

A majority of my students elected to take the spin training and benefitted from it, but I always emphasized that flying the airplane properly was the best way to avoid a stall/spin incident.

Notes:

1. McDaniel, William H.; “The History of Beech”; McCormick-Armstrong Co., Incorporated, Wichita, Kansas; 1982.
2. Ibid
3. Taylor, John W.R.; “Jane’s All The World’s Aircraft;” Jane’s Publishing Company Limited, London, England; 1981.
4. Phillips, Edward H.; “Beechcraft – Pursuit of Perfection;” Flying Books, Publishers and Wholesalers, Eagan, Minnesota; 1992.
5. McDaniel, William H.: “The History of Beech;” McCormick-Armstrong Co., Incorporated, Wichita, Kansas; 1982.
6. Taylor. W.R.; “Jane’s All The World’s Aircraft;” Jane’s Publishing Company Limited, London, England; 1981.
7. Phillips, Edward H.; “Beechcraft – Pursuit of Perfection:” Flying Books, Publishers and Wholesalers, Eagan, Minnesota; 1992.