in ued ▁on ▁ 9 ▁July ▁ 1 9 4 8 , ▁when ▁the ▁Air ▁Pro ving ▁Gr ound ▁Command ▁re organ ized ▁according ▁to ▁the ▁Wing / Base ▁( H ob son ▁Plan ) ▁model . ▁ ▁Line age ▁ ▁Const it uted ▁as : ▁ 2 3 d ▁Compos ite ▁Group , ▁and ▁activ ated ▁on ▁ 1 ▁August ▁ 1 9 3 9 ▁ ▁Red es ign ated ▁as : ▁Air ▁Corps ▁Pro ving ▁Gr ound ▁Det achment ▁on ▁ 1 ▁July ▁ 1 9 4 1 ▁ ▁Red es ign ated ▁as : ▁Air ▁Corps ▁Pro ving ▁Gr ound ▁Group ▁on ▁ 1 0 ▁April ▁ 1 9 4 2 ▁ ▁Red es ign ated ▁as : ▁ 1 st ▁Pro ving ▁Gr ound ▁Group ▁on ▁ 1 6 ▁April ▁ 1 9 4 3 ▁ ▁Dis band ed ▁on ▁ 1 ▁April ▁ 1 9 4 4 . ▁ ▁Ass ign ments ▁ ▁Air ▁Corps ▁T act ical ▁School , ▁ 1 ▁August ▁ 1 9 3 9 ▁ ▁Office ▁of ▁the ▁Chief ▁of ▁Air ▁Corps , ▁ 1 ▁June ▁ 1 9 4 0 ▁ ▁Air ▁Corps ▁Pro ving ▁Gr ound ▁( l ater ▁Pro ving ▁Gr ound ▁Command ), ▁ 1 5 ▁May ▁ 1 9 4 1 ▁- ▁ 1 ▁April ▁ 1 9 4 4 ▁ ▁St ations ▁ ▁Max well ▁Field , ▁Alabama ▁ ▁Army ▁Air ▁Base , ▁Or lando , ▁Florida , ▁ 1 ▁September ▁ 1 9 4 0 ▁ ▁Eg