M/Sgt Ernest J Barker job in the 392nd Bomb Squadron was listed as "Section Chief of Armament (under Lt. Louis)."

From "The History of the 392nd Bombardment Squadron", Nov 1944:

"Operationally, the Armament Section is handicapped by a shortage of personnel. Additional airplanes coupled with personnel lost to various squadron details, continued to impair the overall efficiency. M/Sgt. ERNEST BARKER, T/Sgt. TYRA ROBERTS, and S/Sgt. STEVE SADVARI deserve special commendation in view of their efforts and skill in the successful pursuit of armament and bombsight maintenance."

From "The History of the 392nd Bombardment Squadron", Jun 1945:

"All members of this squadron were detailed to fire their weapons on the range this month. M/Sgt. ERNEST J. BARKER, Armament Section Chief, and Captain KENNETH B. COCHRAN, Gunnery Officer were in charge of the range and instructed the men in range discipline and the regulation positions of firing. Although this has been the first opportunity in almost two years that this squadron has led to fire for record, several qualified as expert and over fifty percent of all who fired qualified as marksmen or above."

The 392nd Bombardment Squadron was assembled at March Field, CA in the fall of 1943. It moved to Barking Sands, Kauai, Hawaii Territory in Oct 1943. In Nov 1943 the squadron moved to Canton Island in the Phoenix Islands, and began combat operations against the Japanese.

Over the next year and a half the squadron kept moving "from one damn island to another". In Jan 1944 the 392nd Bomb Squadron moved to Apamama Island, followed by a move to Kwajalein Island in Mar 1944. Their final move was to Saipan in Aug 1944. They remained there until Feb 1945, at which time they returned to Hawaii. They were sent back to the US in the summer and fall of 1945.

https://30thbombgroup.org/wp-content/uploads/2023/09/392.unit_.history.v02.pdf