Complex sentence: Winfield Bertrum "Bert" Kinner I (16 December 1882--4 July 1957) founded Kinner Airplane & Motor Corporation in Glendale, California which produced radial engines and aircraft.
Split into simpler sentences: Winfield Bertrum "Bert" Kinner I (December 16,1882--July 4,1957) was an American aircraft engine designer and constructor. Kinner founded Kinner Airplane & Motor Corporation in Glendale, California which produced radial engines and aircraft.