Back in the 1950s, Goodyear had a concept for a kind of plane that some thought was improbable. Designed as a way for stricken pilots to extract themselves from behind enemy lines, the Inflatoplane was a rubber aircraft that could be air-dropped in a box, inflated in just five minutes, then flown to safety.
This incredible plane was sent in by a reader and I’m amazed that we’ve only given just a passing mention of it. I will change that right now as this is a wild piece of aviation history.
The concept of rubber planes date back a century as Aviators have long been enamored with the idea of a plane that didn’t kill its occupants in a crash. Back in 1931, HistoryNet notes, Taylor McDaniel would patent what is considered to be the first inflatable plane.
McDaniel’s aircraft was a glider and its first six flights were on January 4. It flew again the next week for the press and during a second flight test it slammed into the ground. The glider was left intact as its wing deflected the impact. The damage? One broken wire. With McDaniel’s creation the concept was set and would be attempted again a number of times.
The Russians and the British both tried their hands at their own inflatable planes. While both reportedly worked, neither project got off of the ground.
This leaves us with Goodyear Aircraft Corporation. In 1956, four years after McDaniel’s death, the company designed and built 12 Inflatoplanes over the course of 12 weeks, notes the Smithsonian.
To improve on structural stability, the Inflatoplanes used Goodyear’s Airmat that consisted of joined layers of inflatable rubber-coated nylon fabric shaped by thousands of nylon threads. This made for a building material that was not just light, but strong enough to work for an aircraft. The fuselage was built out of airship fabric with reinforced areas for the landing gear and a pilot seat.
The first Inflatoplane, GA-33, was a single-seat model similar to the McDaniel glider. Favorable test results led to the improved GA-447.
This one got a new wing and was used for undercarriage testing. This would lead into the GA-468, which had some impressive specs for an inflatable:
The airplane was wheeled out like a wheelbarrow and inflated in about 5 minutes using less air pressure than a car tire. The two-cycle 40-hp Nelson engine had to be hand-started and held 20 gallons of fuel.
The Inflatoplane carried a maximum weight of 240 lb., had a range of 390 mi., and an endurance of 6.5 hr.s. Its cruise speed was 60 mph. Take off distance on sod was 250 ft with 575 ft needed to clear a 50-foot obstacle. It landed in 350 ft on sod. Rate of climb was 550 ft per min. Its service ceiling was estimated at 10,000 ft.
An Inflatoplane could even take some arms fire as the engine also worked to keep the craft inflated. And when it was done flying it could be packed up into a 44 cubic-foot crate, small enough to fit on a Jeep’s trailer or in the back of some cars.
Later, a two-seater was built with a 60 HP engine, an estimated service ceiling of 16,000 feet and a cruising speed of 70 mph. The rubber plane seemed promising and soon the idea was pitched to the public for recreational use. That was right until they started crashing.
The Akron Beacon Journal details the two crashes that ultimately put the whole program into question:
Pilot Ulm narrowly escaped death in April 1959 when the plane crashed into the Patuxent River during a test flight in Maryland. The wing collapsed and hit the propeller, forcing Ulm to bail out with a parachute to safety.
Two months later, disaster struck at Wingfoot Lake.
Army Lt. Malcolm Wallace, 26, of Greenville, Texas, was training on an Inflatoplane when it began to spiral out of control about 700 feet up.
“The engine sounded like it was going to conk out,” witness William Church told the Beacon Journal. “Then the plane went into a spin and the left wing seemed to deflate. The pilot stayed with the plane for a while, then jumped out.”
Wallace didn’t have enough time to open his parachute. He plunged to his death in a marshy area near the lake.
Suddenly, the Inflatoplane seemed less revolutionary and more questionable.
As the above Mustard video notes, there were already doubts that an inflatable plane was really a good way to extract a downed pilot. After all, they’d have to fly through the same area they got shot down in but in a slower, weaker aircraft. Eventually, helicopters became the tool for saving trapped airmen, anyway.
The Inflatoplane was canceled in 1973. Only 12 were built with just three surviving today. The aircraft was a weird idea proven to work, but it never really found its place.