Baer joined the Lafayette Flying Corps in February 1917. In January 1918, he was assigned to N124. In February, the American pilots of N124 transferred to the United States Air Service to form the 103rd Pursuit Squadron. Baer scored his first victory during March and on 23 April 1918, he scored his fifth victory to become the first American ace of the United States Air Service. On the morning of 22 May 1918, Baer scored his ninth victory but was then shot down by a member of Jasta 18, possibly Hans Müller. Badly injured when his SPAD S.XIII crashed near Armentieres, he was captured by the Germans. Baer received the DSC with Oak Leaf Cluster, and the French Croix de Guerre. On 9 April 1919 he became a Chevalier de la Legion d'Honneur.
Born on a farm at Pea Ridge, Gravette, Arkansas, 13 March 1896. He enlisted in the Kansas National Guard on 10 May 1917. He then transferred to the Aviation section of the Signal Corps and was sent to England for further training. He was sent to 65 Squadron in France on 22 May 1918 for operational experience. He scored one victory before being transferred to 148th Pursuit Squadron in July. Here he added a further 11 victories, one of which may have been Lothar von Richthofen who was wounded on 13 August in a fight with the 148th. He won the British DFC and the American DSC and Cluster. He was killed in a flying accident on 1 February 1920. Hamilton Air Force Base on Bermuda was renamed Kindley Field in his memory.
Putnam joined the French Air Service in April 1917 and was assigned to the Lafayette Flying Corps. He was commissioned into the USAS on 10 June and joined the 103rd Pursuit Squadron as acting CO on the 24th. With the 103rd he scored four more victories, bringing his official score to 13. However, many of his victories were gained far over the enemy lines, and so he received no official confirmation. At one stage he was said to have 34 victories, but only 9 of these were made official. If all this was true, then Putnam would have been America's 'ace of aces' by the summer of 1918. David Putnam fell in combat on the afternoon of 12 September in a fight with several enemy aircraft, being hit by several bullets.
From Philadelphia, Pennsylvania, he joined the Aviation section of the Signal Corps, trained at Issodoun and was then assigned to the 22nd Pursuit Squadron. He gained 10 official victories between 27 August and the end of the war. On the afternoon of 8 September 1918, Swaab was wounded while scoring his first three victories near Cirey-Saarburg. Having shot down a two-seater, he was about to land at a German aerodrome when he realized his mistake. Enemy fighters scrambled to intercept Swaab's SPAD S.XIII and he shot down two Fokker D.VII's while making his escape. On 23 October, Swaab shot down a Fokker D.VII that had just destroyed an American balloon. Evidence suggests the German pilot was Max Näther of Jasta 62.
Born in Dongan Hills, Brooklyn, New York on 20 May 1897. George Vaughn attended Princeton University and enlisted in the Aviation section of the Signal Corps in 1917. Completing his training with the British, he began to ferry planes to France. In mid May 1918 he was assigned to the RAF's 85 Squadron, flying SE5a scouts. He scored 7 victories with this unit, and won the DFC before transferring to the 17th Pursuit Squadron on 27 August. Now flying Camels with the 17th as a flight commander, he accounted for a further six enemy machines bringing his total to 13. He was awarded the DSC in September. His biography 'War Flying in France' was published in 1980. He died on 31 July 1989.