From: Bruce Sterling <>
Subject: Viridian Note 54 : The Festo Stingray
To: Viridian List <>

Key concepts: aviation design, inflatable aircraft

Attention Conservation Notice: This product exists, but is not commercially available. Pre-release hype should always be treated with proper caution.


Entries in the Viridian Teakettle Design Contest:

We still have a Russian entry on the way... This contest ends March 20, 01999.

(((Bruce Sterling remarks: Festo is a German multinational specializing in pneumatic control devices. They have a natural interest in unusual applications for compressed air. Festo creates novel, large-scale inflatable buildings (a process they call "airtecture"), which feature giant inflatable Y-shaped beams, big inflatable girders, and computer controlled tension- cables. Given these bizarre structures, apparently an aircraft somehow came to mind. The Festo "Stingray," designed by a small Swiss company, seems to be a fancy conceptual showpiece for Festo´s core competencies. It is a translucent two-man aircraft made mostly of membranes, compressed air, and computer-controlled wire. The Stingray is something like a rigid, tough, high-tech, flying, intelligent, air mattress. With a little extra development work, the Stingray would work and look much like the flying soap-bubble of Glinda the Good Witch in THE WIZARD OF OZ. This aircraft is nonmetallic, fibrous, and collapsible. It uses "less mass and more data." Most Viridian of all, it consumes very little fuel. Every high-tech CEO now fouling the skies with a fuel-hogging GulfStream should consider floating serenely into town in one of these elegant devices.)))

Source: Sunday Times of London, January 24, 1999

"Inflatable aircraft set for take off

"OWNING an aircraft could become cheaper and far more convenient when a new inflatable plane is launched. Trials of three new craft are taking place in Germany to prove that conventional materials could be replaced by lightweight polyester sheeting stretched across an aluminum frame.

"Festo, the Stuttgart manufacturer behind the trials, already markets inflatable buildings and ballooning baskets. It says the unconventional aircraft are being designed to prove that plastic sheet is safe and can cut a third off the cost of owning and running a plane.

"The most striking of the three designs is a delta- shaped plane called Stingray that has already flown in tests for more than 250 hours.

"Its name is derived from its unusual take-off method. First the pilot must rev the two 28hp engines with the brakes on. He then presses a button that releases a telescopic rod that strikes the ground and lifts the craft two metres into the air. At the same time a computer releases the brakes and Stingray is airborne, its engines moving it forward. The ´blended wing´ design allows it to gain altitude.

"Axel Thallemer, head of design at Festo, claims the craft is sturdy and will not plummet to the ground if punctured.

"´The sheeting can take several tonnes of pressure per metre," he says. ´Also, the air inside the craft is not at a high pressure, particularly at high altitudes, so if there is a tear it will not gush out instantly. We estimate a pilot would have 30 minutes to land before the plane became uncontrollable. It would be difficult to rip the lining because it is incredibly strong. The yarn is made in a similar way to the material in bullet-proof vests.´ (...)

"´People don´t believe we can fly a plane with just two 28hp engines," says Thallemer. ´But because the design is so light we can get away with it.´ (...)

"´We don´t know for sure if, after testing, Stingray will be launched commercially. We are simply doing it to show that there is more to construction than conventional materials. Air is all around us so it makes sense to use it and cut down on weight.´ (...)

"Festo is also testing an inflatable hang glider, called Pneumagic, and an ultra-light single-seat plane, called Pneuwing.

"Both have pumps that automatically inflate and deflate the polystyrene covering that surrounds the aluminium fuselage.

"Pneumagic has a nine-metre wingspan but when deflated it fits in a rucksack."


"The media talked about a ´flying stingray´ when Prospective Concepts AG finally unveiled its secretive technology demonstrator in May 1998. Stingray is indeed an appropriate name for the groundbreaking aircraft designed by this small Swiss company.

"The Stingray has a revolutionary wing that derives its rigidity from compressed air. Later versions will be filled with helium. The second radical concept developed especially for the Stingray is a pneumatic catapult to be placed in the aircraft´s tail. (...)

"As the founder and president of Prospective Concepts Andreas Reinhard notes, the Stingray constitutes the high end in the use of pneumatic structures. It is thus a showcase and the pioneer of a technology which uses high strength fiber materials and air pressure as its components. With the use of this technology, rigidity and flexibility can be combined, a union that seemed contradictory up to now."

The Festo Stingray was first brought to our attention by:

Tor Kristensen ( **)