USA
One-time sales representative of the Curtiss Aeroplane and Motor Co, G. S. Ireland founded his company to manufacture an aircraft known as the Ireland Comet, which combined surplus-Curtiss Oriole fuselages with new wings and tail unit. Incorporated in 1926, the company began production of the Ireland Neptune, a five-seat amphibian flying-boat.

Karlis Irbitis is one of the pioneers of the aircrafts design in Latvia. In his early years Latvia was part of the Russia and he had chance to see some of the Russians war machines of French origins. His early attempt to build aircraft failed when his Nieuport replica crashed so he turn his interest in the modeling.

Karlis Irbitis has enrolled into the Mechanical Engineering Facility and spent time on airframe maintenance for the newly formed Latvian Air Force. In 1925 Irbitis met Nicholas Pulins. Mr. Pulins had an interest in light aviation and Irbitis influencec him to start building a high wing monoplane with Anzani engine. Previously Pulins have interest in biplanes. With the financial support, Irbitris made his first aircraft, the I-1 and it had its maiden flight on 13th June 1925. The I-1 was a single seat airplane and followed by the I-2, two seat aircraft and name Ikarus. On I-2 both, Irbitis and Pulins learn to fly.

After military service, Karlis Irbitis start work as designer in the A.S. Backman company and main work was focused on repairing of aircraft for Latvia. His first work was on Hansa Brandenburg W.29 and this was hard due to the lack of the technical documentation. After several projects A.S. Backman was bankrupted and closed in 1930 and Karlis Irbitis joined the Valsts Elektrotechniska Fabrika electric company. In the 1935 he submit proposal for the company to built aircraft and an aircraft construction division was established in the same year with Irbitis as the head of the division. The very first project was I-11, powered with Minor 90 HP engine and its maiden flight was in July 1936.

USA

In the late 1920s the Invincible Metal Furniture Company of Manitowoc, Wisconsin, formed an aircraft division to build a four-seat cabin monoplane. The fuselage and tail unit were welded steel-tube structures, the wing of wooden construction. Access to the cabin was by a completely circular door on the starboard side of the fuselage.