This idea is actually baked. In the late 1940s/early 1950s Goodyear designed and built several prototype inflatable aircraft. They were hardly "ultralight," since they weighed over 500 lbs, but advances in materials technology and engine design could surely produce a craft that weighed under 250 lbs. The applications could be recreational, rescue (air-drop a deflated plane to a stranded pilot or intelligence operative) or ?
-- whlanteigne, Sep 28 2002

BBD - Big Black Delta http://www.space.co...riangle_020805.html
(UFO-lore) [Shz, Oct 04 2004, last modified Oct 21 2004]

Prospective Concepts Stingray http://hotairship.c...abase/prospect.html
...you mean kind of like this? [BunsenHoneydew, Oct 04 2004, last modified Oct 21 2004]

(???) URL moved from the [whlanteigne] post http://www.geocitie...7/inflatoplane.html
[bristolz, Oct 04 2004, last modified Oct 21 2004]

Square ram-air chute and a fan http://www.poweredparachuteworld.com/
Slow but ultralight-legal [FloridaManatee, Oct 04 2004, last modified Oct 21 2004]

This'll fit in your trunk http://www.paratoys.com/skymotors.html
Its a fan that you strap to your back. [mortenal, Oct 04 2004, last modified Oct 21 2004]

This is a decent idea, I'm surprised that no one has commented.
-- 2 fries shy of a happy meal, Jan 06 2003


Hypothetically... OK

I am a qualified pilot and I have 40 hours in ultralights and 60 jumps skydiving, so I've got some experience here.

The reason you don't see these things is inflatables do not offer much in the way of rigidity. Also, any aircraft that depends on inflatables for structural integrity would scare the pants off me.

There are however, aircraft that do depend to a large extent on inflatable parts:

(1) All lighter-than-air aircraft - hot air balloons, airships; use inflatable structures to minimise weight

(2) Inflatable wing - powered parachutes, paragliders; inflation comes from ram-air action; can be easily carried and stowed

(3) Pressurized structures- Full Lotus inflatable seaplane floats; light weight and damage resistant

(4) Skirted A/C - hovercraft flies using an inflated skirt to increase lifting performance

I know these aren't exactly what you meant, and your idea probably combines more than one of the above, so here's your croissant. (+)
-- FloridaManatee, Jan 06 2003


I don’t think it will fit in the trunk – they’re pretty big. <link>
-- Shz, Jan 06 2003


Yeah, but who wants to fly in their trunk anyhow?
-- 2 fries shy of a happy meal, Jan 06 2003


Check out the Stingray, and other pneumatic-wing aircraft from Swiss company Prospective Concepts (link). Won't fit in the boot. A paragliding chute will fit in a backpack, though...
-- BunsenHoneydew, Jan 18 2003


This is what I had in mind, already somewhat baked, but lighter, weighing under 250 lbs to meet ultralight specs.

[URL moved to where ALL URLs in halfbakery ideas should be]

"The Inflatoplane was one of those might have been airplanes designed by the Goodyear Company in the 1950's. The design of the plane was to provide for an inflatable rubber airplane that could be used for military purposes.

The Inflatoplane performed in capabilities comparable to a J3 Cub. The aeroplane was wheeled out like a wheelbarrow on its own wheel and inflated using less air pressure than a car tire in about 5 minutes. The aircraft used a two-cycle 40 horsepower Nelson engine that had to be hand started. It's wing span was 22 feet and had a length of 19 feet 7 inches. The airplane held 20 gallons of fuel and carried a maximum weight of 240 lbs. The range of this airplane was 390 miles with an endurance of 6.5 hours. Its' cruise speed was 60 mph. Take off on sod was in 250 feet with 575 feet needed to clear a 50 foot obstacle. It landed in 350 feet on sod. Rate of climb was 550 feet per minute. Its' service ceiling was estimated at 10,000 feet.

The inflatoplane could be dropped by container behind lines for downed pilots to use to be rescued. It was ideally suited for both land and water uses. Later designs included a 42 hp engine and a two place inflatoplane design.

A total of twelve Inflatoplanes were built. Development, testing, and evaluation of the inflatable airplane continued through 1972 and the project finally was laid to rest in 1973. Goodyear donated two Infaltoplanes, one to the Franklin Institute in Philadelphia, and one to the Smithsonian Institute in Washington, D.C."
-- whlanteigne, May 18 2003


This is not theoretical. the "Inflatoplane" did work. It was an U.S. Army project. The theory was that these planes could be dropped behind enemy lines so pilots could self rescue themselves. They exhibited great strength at relatively low air pressures (7 to 8.5 PSI) a man could stand on the wing just outboard of the guy wires. Most models were amphibious and single person. this project was ended in 1973 or so. The army just did not like the idea of an aircraft that was easy to shoot holes in. A few good shots with a wrist rocket (slingshot) could probably cause a leak that the on-engine pump could not keep up with. With modern materials this plane could be even lighter and stronger than in 1973. I think the concept should be reevaluated for disaster and rescue work. These planes would have been very handy in Louisiana after the hurricane.
-- LoboCal, Jul 19 2008


//aircraft that do depend to a large extent on inflatable parts://

To that list should be added inflatable tires. The aircraft that does not land on inflatable tires is a rare exception. The rest routinely drop the entire aircraft onto their inflatable tires, while the aircraft is moving at landing speed and the tires aren't even rolling, then apply braking force through the tires, roll out and taxi around, then park on the poor things.

I'm just saying that inflatable airplane parts are in taken-for-granted use, and incredibly dependable. That may not be relevant to this discussion.
-- baconbrain, Jul 19 2008



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