The company specialized in the manufacture of ultralight aircraft in the form of kits for amateur construction.

When Teratorn went out of business in about 1989, the Tierra designs were put back into production by Golden Circle Air of De Soto, Iowa, as the Golden Circle Air T-Bird line.

Golden Circle Air went out of business in about 2006, and Indy Aircraft was formed to provide parts for the existing fleet.

More than 1500 Tierra/T-Bird Is and 2500 Tierra II/T-Bird IIs have been constructed by all manufacturers of the types in total.

The new company offers new kits and parts for the T-Bird I and II, refurbishing of old kits, and are developing a new design, the Tbird TU, to conform to FAR Part 103 requirements.