Beechcraft Model 34
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The Beechcraft Model 34 "Twin-Quad" was a prototype
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designed and built by
Beechcraft Beechcraft is an American brand of civil aviation and Military aircraft, military aircraft owned by Textron Aviation since 2014, headquartered in Wichita, Kansas. Originally, it was a brand of Beech Aircraft Corporation, an American manufacture ...
in the period between
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and the
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.Phillips 1992 At this time many aircraft manufacturers in the
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anticipated a boom in
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and a large number of designs left the drawing board only to ultimately fail. The Model 34 was one of these failures, partly because of its unusual design, and partly because of the thousands of ex-military transport aircraft that were available at the time for a fraction of the price of a new aircraft.


Design and development

The design was a four-engine high-wing
monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...
with
tricycle undercarriage Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', that is arranged in a tricycle fashion. The tricycle arrangement has one or more nose wheels in a single front undercarriage and two or more main wheels slightly aft of th ...
, originally designed for 14 (three abreast seating with six additional seats mounted on the side) and eventually converted to take 20 passengers. The side "couch seats" were also able to be folded away so that cargo could be carried internally in the cabin. Individual storage space was provided for each passenger seat on the fuselage side above the seat. In order to accommodate a larger cargo load, a cargo hatch was located near the pilot's compartment.Neal 1970. p. 15. The unusual aspects of the design were the butterfly or V-tail and engine layout that led to its popular nickname, "Twin Quad." The four engines were buried in the wings, with each pair of engines connected to a single propeller via
clutch A clutch is a mechanical device that allows an output shaft to be disconnected from a rotating input shaft. The clutch's input shaft is typically attached to a motor, while the clutch's output shaft is connected to the mechanism that does th ...
es and a common
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. The engines were
horizontally opposed A flat engine is a piston engine where the cylinders are located on either side of a central crankshaft. Flat engines are also known as horizontally opposed engines, however this is distinct from the less common opposed-piston engine design, ...
eight-cylinder air-cooled
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s (GSO denoting "Geared Supercharged and Opposed", with each engine featuring a built-in reduction gear box in addition to the common propeller gear box). The engines were rated at 400
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at 3,300
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. The tail was unusual because unlike the vertical and two horizontal surfaces found on most aircraft, the Twin-Quad's was a two-surface V-tail similar to the tail fitted to Beechcraft's other new product at the time, the Model 35 Bonanza. The V-tail configuration was flight-tested on a twin-engine Beech AT-10. Another, but more conventional, design aspect was that the belly was made strong enough to sustain minimal damage in the event of a "wheels-up" landing, with built-in integral landing keels or "skids."Neal 1970, pp. 16–17. The wing measured from tip to tip and the fuselage was long. With the top of the V-tail almost above the ground and a design maximum takeoff weight (MTOW) of 20,000 lbs, the Model 34 is to date the largest and heaviest Beechcraft civil design, with only the smaller XA-38 Grizzly military aircraft outweighing it.


Operational history

The Model 34 took to the air for the first time on October 1, 1947, with Beech Chief Pilot Vern L. Carstens at the controls. The first flight was uneventful and the initial report from the test pilot was, "We have another outstanding Beechcraft!" The prototype Model 34 had accumulated more than 200 hours of test flying when the reinforced belly was validated in a wheels-up landing.Simpson 1991, p. 42. On January 17, 1949, in a severe
forced landing A forced landing is a landing by an aircraft made under factors outside the pilot's control, such as the failure of engines, systems, components, or weather which makes continued flight impossible. However, the term also means a landing that has ...
a few miles northwest of the Beech plant shortly after taking off, the sole Beech 34 was damaged beyond repair. An inadvertent cutting off of an emergency master switch when battling an electrical fire had resulted in the shut down of all the powerplants, leading to the crash. The co-pilot was killed and the pilot and two flight observers were injured in the crash.Neal 1970, p. 17. After the accident, Beech re-evaluated plans to go into series production with the Model 34. At the time, two new prototypes were being manufactured, one for static test and the other to continue the flight test program. One of the main considerations was that the U.S.
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was delaying the licensing of the anticipated "feeder airlines" for which the design was intended.Neal 1970, p. 64. The Beech 34 ultimately could not compete in major and regional airline operations with the thousands of less complex and cheaper war surplus transports, such as the larger
Douglas DC-3 The Douglas DC-3 is a propeller-driven airliner manufactured by the Douglas Aircraft Company, which had a lasting effect on the airline industry in the 1930s to 1940s and World War II. It was developed as a larger, improved 14-bed sleeper ...
/
C-47 Skytrain The Douglas C-47 Skytrain or Dakota ( RAF designation) is a military transport aircraft developed from the civilian Douglas DC-3 airliner. It was used extensively by the Allies during World War II. During the war the C-47 was used for troo ...
, the similarly sized C-60 Lodestar and Beechcraft's own smaller
Beechcraft Model 18 The Beechcraft Model 18 (or "Twin Beech", as it is also known) is a 6- to 11-seat, twin-engined, low-wing, tailwheel light aircraft manufactured by the Beechcraft, Beech Aircraft Corporation of Wichita, Kansas. Continuously produced from 1937 ...
. Despite its promise, since the "Twin Quad" had attracted no orders, Beech terminated the project, closing down the production line in January 1949.


Specifications (Model 34)


See also


References

;Notes ;Bibliography * ''
Illustrated Encyclopedia of Aircraft The ''Illustrated Encyclopedia of Aircraft'' was a weekly partwork magazine by Aerospace Publishing (an imprint of Orbis Publishing) which was published in the United Kingdom (and sold in other countries too) during the early 1980s. The magazi ...
'' (Part Work 1982–1985). London: Orbis Publishing, 1985. * Neal, Ronald D. "Pioneer Without a Cause." ''Air Classics'', Vol. 6, no. 4, April 1970. * Phillips, Edward H., ''Beechcraft - Pursuit of Perfection, A History of Beechcraft Airplanes''. Eagan, Minnesota: Flying Books, 1992. . * Simpson, R.W. ''Airlife's General Aviation''. Shrewsbury, UK: Airlife Publishing, 1991, .


External links


"Beech Twin-Quad Power Plant"
a 1949 ''Flight'' article on the coupled engine installation on the Model 34 {{Beechcraft 0034 Abandoned civil aircraft projects of the United States 1940s United States airliners V-tail aircraft Four-engined twin-prop tractor aircraft High-wing aircraft Aircraft first flown in 1947 Four-engined piston aircraft Aircraft with retractable tricycle landing gear