Credited with 44 aerial victories during World War I, he was one of Germany's leading flying aces, as well as commander of one of the first Imperial German Air Service Jagdeschwaders.

In November 1917, he and his squadron mate Göring each had 15 kills, and both still coveted the highest Prussian decoration - the blue enamel cross of the Pour le Mérite.

Leading Jasta 26 and three other squadrons, with Hermann Dahlmann's support as adjutant and wingman, Loerzer proved a successful wing commander.

Equipped with the new BMW-engined Fokker D.VII, JG III cut a wide swath through Allied formations in the summer of 1918, and his own score mounted steadily.

During the 1930s he was a leader in various civil aviation organizations (National Socialist Flying Corps: NSFK), and rejoined the Luftwaffe in 1935 with the rank of Oberst (colonel).

His unit was transferred to Messina, Sicily in October 1941, and he remained there until the middle of 1943, when his section returned to the Italian mainland after suffering heavy losses.

In December 1942, fighter ace Werner Baumbach, Group Commander of III./Kampfgeschwader 30, wrote a letter to Hans Jeschonnek, then Chief of the General Staff of the Luftwaffe, regarding the heavy losses suffered by the II Air Corps under Loerzer's leadership.