Made On Earth — Open Source Soaring

Craft & Design
Made On Earth — Open Source Soaring


We may all dream of flying silently through the clouds, but Mike Sandlin has actually created a set of gliders that allow you to fly with only the power of gravity.

Using his expertise in building hang gliders, Sandlin prototyped a slow-flying, ultralight sailplane that he calls an “airchair.” Airchairs are basically hang gliders with seats, that steer like an airplane. Beginning with his Basic Ultralight Glider (Bug) in the 1990s, Sandlin has pioneered a unique field of powerless aviation.

His airchairs include the biplane Bug series, monoplane Goat series, and his current creation, the rudder-steered Pig series. Instead of selling plans like most small aircraft designers, Sandlin provides the source CAD drawings free for download.

The airchair is designed to be loaded on top of a car for quick setup and disassembly. The pilot launches the glider by rolling down a small incline, usually at hang-glider launch sites.

Sandlin says his gliders are “intended to provide open air soaring, forgiving flight characteristics, convenient transport, simple ‘garage technology’ construction, and a high level of crash safety,” all major accomplishments for machines that weigh less than 155 pounds.

The Pig (Primary Instruction Glider) is a biplane design that features a two-axis control system, which is much easier for beginner pilots. It’s slow, but easy to fly, while still maintaining a decent level of safety for the pilot. Assembly can be accomplished in less than an hour with minimal tools.

Although Sandlin prefers to avoid working with motors, his design has incorporated a space for a small pusher motor attachment on the Pig. With a small motor, the Pig could hop between thermals, staying airborne for hours on end.

So, when will Pigs fly? As it happens, they’re flying right now, and with Sandlin’s help, you could fly a Pig of your own!

>> Basic Ultralight Gliders:

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Abe Connally

Abe Connally and Josie Moores live with their two sons off the grid in the mountains of the Chihuahuan Desert. They develop innovative and practical solutions to homesteading on a budget. is the online documentation of their experiments and adventures.

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