Complex sentence: The airfield was built circa 1942 as part of the Army Airfields in the Orlando area, as an auxiliary to the Bushnell Army Airfield and Zephyrhills Army Airfield.
Split into simpler sentences: The airfield was built about 1942 as part of the construction of Army Airfields in the Orlando area. It was built as an auxiliary to the Bushnell Army Airfield and Zephyrhills Army Airfield.