Blaha received his pilot wings at Williams Air Force Base, Arizona, in 1967. He was subsequently assigned as an operational pilot flying F-4, F-102, F-106, and A-37 aircraft (completing 361 combat missions in Vietnam). He attended the USAF Aerospace Research Pilot School at Edwards Air Force Base, California, in 1971, and piloted the NF-104 research aircraft to 104,400 feet. Following graduation, he served as an F-104 instructor pilot at the test pilot school, teaching low lift-to-drag approach, zoom, performance, stability/control, and spin flight test techniques. In 1973, he was assigned as a test pilot working with the Royal Air Force at the Aeroplane and Armament Experimental Establishment, Boscombe Down, United Kingdom. During a three-year tour, he flew stability/control, performance, spin, and weapons delivery flight tests in the SEPECAT Jaguar, Blackburn Buccaneer, BAE Hawk, and BAC Jet Provost aircraft. In 1976, he attended the U. S. Air Force Air Command and Staff College. After graduation, he was assigned to work for the Assistant Chief of Staff, Studies and Analyses, at Headquarters USAF in the Pentagon. During this tour, he presented F-15 Eagle and F-16 Fighting Falcon study results to Department of Defense, State Department, and Congressional staffs.