▁Army ▁in ▁the ▁United ▁States ▁Army ▁and ▁Fle et ▁Admir al ▁in ▁the ▁United ▁States ▁Navy . ▁The ▁rank ▁has ▁been ▁held ▁only ▁once ▁in ▁history , ▁by ▁General ▁Henry ▁H . ▁Arnold , ▁who ▁served ▁as ▁head ▁of ▁the ▁United ▁States ▁Army ▁Air ▁Forces ▁during ▁World ▁War ▁II . ▁ ▁History ▁ ▁Army ▁Air ▁Forces ▁The ▁term ▁" General ▁of ▁the ▁Air ▁Force " ▁was ▁first ▁inform ally ▁used ▁in ▁ 1 9 4 4 ▁after ▁General ▁Henry ▁H . ▁Arnold ▁was ▁promoted , ▁along ▁with ▁other ▁senior ▁World ▁War ▁II ▁American ▁officers , ▁to ▁the ▁rank ▁of ▁General ▁of ▁the ▁Army . ▁Arnold ▁was ▁at ▁that ▁time ▁head ▁of ▁the ▁United ▁States ▁Army ▁Air ▁Forces ▁which ▁had ▁become ▁its ▁own ▁branch ▁of ▁service ▁in ▁all ▁but ▁name . ▁To ▁differenti ate ▁Arnold ▁from ▁the ▁other ▁five - star ▁gener als ▁in ▁the ▁regular ▁U . S . ▁Army ▁( such ▁as ▁D w ight ▁Eisen h ower ▁and ▁Douglas ▁Mac Ar thur ), ▁Arnold ▁was ▁commonly ▁referred ▁to ▁as ▁" General ▁of ▁the ▁Air ▁Force ▁Arnold " ▁in ▁all ▁but ▁official ▁correspond ence . ▁In ▁official ▁documents , ▁his ▁rank ▁was ▁listed ▁as ▁" General ▁of ▁the ▁Army ▁( USA AF ) ". ▁ ▁Post - W ar ▁ ▁On ▁September ▁ 1 8 , ▁ 1 9 4 7 , ▁the ▁United ▁States ▁Air ▁Force ▁was ▁founded ▁as ▁a ▁separate ▁branch ▁of ▁service . ▁For ▁the ▁first ▁few ▁months ▁of ▁its ▁existence , ▁U . S . ▁Air ▁Force ▁ranks