Ryan Aircraft manufactured four and six-place cabin monoplanes at their St. Louis facility, adjacent to the municipal airport.

Incorporated in Michigan, June 11, 1929, to take over and continue the development of automatic riveting machines and their application to all types of aircraft.

Owned and operated an airport on Grosse Ile, an island in the Detroit River.

The airport covered 403 acres (1.63 km2) of land and has water approaches on three sides.

Incorporated in Michigan, June 11, 1929, to specialise exclusively in all-metal amphibian and flying boat construction for commercial and naval uses.

Incorporated in Michigan, May 20, 1929. to acquire design and patent rights on entire line of metal aircraft of Blackburn Airplane & Motor Co., Ltd. of England.

Incorporated in December 1928 for the purpose of handling export sales in South and Central China.

[13][failed verification] The Lockheed Aircraft Company of Santa Barbara, California had been a going concern all throughout the 1920s.

However, in 1929, the management of Lockheed voted to sell majority share ownership to the Detroit Aircraft Corporation.