Introducing the Basic Ultralight Gliders

The Pig1, Goats1 & 4, and Bug4, are home built, basic ultralight gliders. Technically these aircraft are ultralight sailplanes, but they are best described as "airchairs", which are simple, slow flying gliders with the pilot sitting out in the open air rather than inside a fuselage.

My airchair dersigns are intended to provide open air soaring, forgiving flight characteristics, convenient transport, simple "garage technology" construction, and a high level of crash safety. In the United States, all unpowered ultralights, including paragliders, hang gliders, and airchairs are regulated under FAR Part 103, which allows gliders to be built and flown with no direct official oversight as long as they weigh less than 155 lbs.

The complete descriptive drawings of the Pig1, Goat4, Bug4, and some of their predecessors are free and available for downloading in CAD format (select "Drawings" from menu above). In addition, the the Goat4 drawings can be viewed on the Web. My activities are noncommercial and all of the materials on my website are available for whatever purposes the user may consider worthwhile.

Quick assembly & roof rack transport make flying convenient. A Bug, Goat, or Pig can be strapped down onto an ordinary hang glider rack, with no special saddles or pads. Here we see me with Bug4 on my truck, ready to roll down the highway.

Truck Tow An airchair can be launched by ultralight aerotow, car tow, winch cable, or just by rolling down an open slope. Ultralight Aero Tow

Rolling Launch

My gliders fly at about the same speeds as a hang glider, readily mixing with hang glider and paraglider traffic. No formal performance measurements have been made, but all are in the hang glider range and can stay up in good lift conditions. I designed, built, and flew the Bug2, Bug4,Goats 1-4, and the Pig. In the Bug and Goats and have soared thousands of feet above take off altitude in each of them (Pig1 has flown high but not soared as of this writing).

Open air soaring is a special kind of adventure. Here my feet are out in the breeze as I soar my airchair high over the California desert.

A Basic Ultralight Glider is not a hang glider (it cannot be foot launched) nor is it what is usually meant by an ultralight airplane (it has no engine). Its construction is "low tech", at the hand drill and hacksaw level, for easy home building, from readily available materials (it is made mostly from aluminum tubing and steel cable with polyester fabric covering).



Bug4, (and Goats & Pig) are light and simple. Folding wing design provides a large area wing in a small, light package, allowing transport & assembly by one person.

Center stick & rudder pedals provide a traditional control system.

Construction is of aluminum tubing and steel cable covered with a heat shrunk fabric.

The Basic Ultralight Gliders are best characterized by their light wing loading, which is about the same as that of a hang glider (around 1.7 lb. of gross weight for every square foot of wing area). Light wing loading results in slow flight, which is safe, comfortable, and allows soaring in small thermals (because of the ability to turn tightly).

Slow flight provides the unique ability to self launch by rolling down open slopes, usually at the same mountain launch sites used by hang gliders and paragliders. This rolling launch has become a standard procedure for local weekend soaring. The launch slope I most often use has a vertical drop of about 17 feet over a rolling distance of 72 feet (so, the rolling distance is two wing spans for the Goat). I launch here only with a headwind; a longer slope is required (by me) for calm air launching.





Photo by Floyd Fronius, in Goat1

Links:

Airchair Discussion Group (Yahoo Forum)

Airchair-wiki (airchair information, broadly gathered & activly edited)

HillHopper Page

Experimental Soaring Society (formerly: Sailplane Homebuilder's Association )

"X Gliders", my experimental hang gliders

Drogue Chute Page

freeware, thanks t o .... Irfanview (photo viewer) ...... Beamboy (beam analysis )......

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