08/15/2008. The second Model 30 was completed in September 1943, differing from Ship number 1 in having an enclosed two-seat cabin. Ship number 2 made its public debut in March 1944. On May 10, it became the first US helicopter flying indoors, when Floyd Carlson flew the aircraft inside the US Army 65th Regiment Armory, at Buffalo, New York. View also photo 9798.