Connelly transferred from the French Foreign Legion to the Lafayette Flying Corps where he received his Pilot's Brevet in November of 1917, he was assigned to Spa157 on January 15, 1918. Flying the SPAD S.VII, he scored two victories before being reassigned to Spa163 onJune 27 , 1918. He served with this Escadrille for the rest the war, scoring five more victories.

Médaille Militaire
"Voluntarily enlisted for the duration of the war, has become indispensable by greatness of his character, his qualities as a pilot, and his complete contempt for danger. On 6 September 1918, he reported his fifth victory by downing an enemy scout. Three citations." Médaille Militaire citation

Distinguished Service Cross (DSC)
"Distinguished himself by extraordinary heroism in connection with military operations against an armed enemy of the United States at Suippes, France, onSeptember 6, 1918, and in recognition of his gallant conduct, I have awarded him, in the name of the President, the Distinguished Service Cross." J.J. Pershing, Commander-In-Chief, United States Air Service