Goodyear Inflatoplane
Encyclopedia
The Goodyear Inflatoplane was an experimental aircraft made by the Goodyear Aircraft Company, a subsidiary of Goodyear Tire and Rubber Company
Goodyear Tire and Rubber Company
The Goodyear Tire & Rubber Company was founded in 1898 by Frank Seiberling. Goodyear manufactures tires for automobiles, commercial trucks, light trucks, SUVs, race cars, airplanes, farm equipment and heavy earth-mover machinery....
, well known for the Goodyear blimp
Blimp
A blimp, or non-rigid airship, is a floating airship without an internal supporting framework or keel. A non-rigid airship differs from a semi-rigid airship and a rigid airship in that it does not have any rigid structure, neither a complete framework nor a partial keel, to help the airbag...
. Although it seemed an improbable project, the finished aircraft proved to be capable of meeting its design objectives although its sponsor, the United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
, ultimately cancelled the project when it could not find a "valid military use for an aircraft that could be brought down by a well-aimed bow and arrow."
Design and development
The original concept of an all-fabric inflatable aircraftAircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
was based on Taylor McDaniel inflatable rubber glider experiments in 1931. Designed and built in only 12 weeks, the Goodyear Inflatoplane was built in 1956, with the idea that it could be used by the military as a rescue plane to be dropped in a hardened container behind enemy lines. The 44 cubic ft (1.25 cubic meter) container could also be transported by truck, jeep trailer or aircraft. The inflatable surface of this aircraft was actually a sandwich of two rubber-type materials connected by a mesh of nylon threads, forming an I-beam. When the nylon was exposed to air, it absorbed and repelled water as it stiffened, giving the aircraft its shape and rigidity. Structural integrity was retained in flight with forced air being continually circulated by the aircraft's motor.
There were at least two versions:
The GA-468 was a single-seater. It took about five minutes to inflate to about 25 psi (172.4 kPa); at full size, it was 19 in 7 in (5.97 m) long, with a 22 ft (6.7 m) wingspan. A pilot would then hand-start the two-stroke cycle
Two-stroke cycle
A two-stroke engine is an internal combustion engine that completes the process cycle in one revolution of the crankshaft...
, 40 hp Nelson engine, and takeoff with a maximum load of 240 pounds (108.9 kg). On 20 US gallon
Gallon
The gallon is a measure of volume. Historically it has had many different definitions, but there are three definitions in current use: the imperial gallon which is used in the United Kingdom and semi-officially within Canada, the United States liquid gallon and the lesser used United States dry...
s (76 L) of fuel, the aircraft could fly 390 miles (627.6 km), with an endurance of 6.5 hours. Maximum speed was 72 miles per hour (115.9 km/h), with a cruise speed of 60 mph. Later, a 42 hp engine was used in the aircraft.
Takeoff from turf was in 250 feet with 575 feet needed to clear a 50 foot obstacle. It landed in 350 feet. Rate of climb was 550 feet per minute. Its service ceiling was estimated at 10,000 ft.
The GA-466 was the two-seater version, 2 in (50.8 mm) shorter, but with a 6 ft (1.8 m) longer wingspan than the GA-468. A more powerful 60 hp McCulloch 4318 engine could power the 740 pounds (335.7 kg) of plane and passenger to 70 miles per hour (112.7 km/h), although the range of the plane was limited to 275 miles (442.6 km).
Operational history
Akron, Ohio
Akron , is the fifth largest city in the U.S. state of Ohio and the county seat of Summit County. It is located in the Great Lakes region approximately south of Lake Erie along the Little Cuyahoga River. As of the 2010 census, the city had a population of 199,110. The Akron Metropolitan...
showed that the inflation could be accomplished with as little as 8 psi (544 mbar), less than a car tire. The flight test program had a fatal crash when Army aviator Lt. "Pug" Wallace was killed. The aircraft was in a descending turn when one of the control cables under the wing came off the pulley and was wedged in the pulley bracket, locking the stick. The turn tightened until one of the wings folded up over the prop and was chopped up. With the wings flapping because of loss of air, one of the aluminum wing tip skids hit the pilot alongside the head, as was clear from marks on his helmet. Wallace was pitched out over the nose of the aircraft and fell into the shallow lake. His chute never opened. He may have been knocked unconscious and rendered unable to open it. Only 12 Goodyear Inflatoplanes were built, but development continued until the project was cancelled in 1973.
Survivors
Goodyear donated two Inflatoplanes for museum display at the end of the project, one to the Franklin InstituteFranklin Institute
The Franklin Institute is a museum in Philadelphia, Pennsylvania, and one of the oldest centers of science education and development in the United States, dating to 1824. The Institute also houses the Benjamin Franklin National Memorial.-History:On February 5, 1824, Samuel Vaughn Merrick and...
in Philadelphia and one to the Smithsonian Institution
Smithsonian Institution
The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...
in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
Variants
GA-33 Inflatoplane- The initial single-seat version, with open cockpit, based on the Taylor McDaniel inflatable rubber glider experiments from the early 1930's. One built.
GA-447 Inflatoplane
- An enclosed cockpit and new wing, used for undercarriage experiments (tricycle, uniwheel, and hydroskid). One built.
GA-466 Inflatoplane
- Company designation for the AO-2 Inflatoplane
GA-468 Inflatoplane
- Company designation for the AO-3 Inflatoplane
XAO-2-GI Inflatoplane
- Military designation for the GA-466. One built.
XAO-3-GI Inflatoplane
- Military designation for the GA-468. Five built.