Frank G. Tinker, Jr. was the top American ace flying under contract with the Spanish Republican Air Force in the Spanish Civil War. This first in-depth biography of Tinker covers his experience in combat, culminating with his commanding a Soviet squadron and terminating his contract with the government of Spain. The authors, well-known aviation historians, also offer a rare discussion of the aerial tactics introduced in the Spanish Civil War that became standard procedures in World War II and firmly establish Tinker's aviation feats for the historical record.