According to USAAF and 8AF records of losses, he was killed with nine other members of his crew on B-17F 42-29934 over Nantes on September 16, 1943, when bombs dropped from an airplane above his airplane caused it to crash.
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Bombardier of B-17F tail No. 42-29934 of the 379th Bomb Group, 526th Bomb Squadron. On a bombing mission to Nantes, France, September 16, 1943, his B-17 was struck by a bomb dropped from another B-17 in the formation, and crashed with no survivors.

Note: Several Find-a-Grave entries for crew members note a death date of Aug. 12, 1945, but that was the date they were declared dead for legal and insurance reasons, and the cause of death is given as "an aerial bomb from an enemy fighter," an omission/whitewashing of the fact they were killed by American bombs dropped out of formation.

Note added 2019-11-16: The 8th Air Force Historical Society website cited above has moved to a paywall, so a search no longer is possible. Other websites also list this cause of loss, citing Missing Air Crew Report (MACR) 1348. Confusingly, some site list both an errant bomb AND enemy AAA fire, and it is possible both contributed to the loss of this bomber and its gallant crew. Further research is needed.

The lost crew members were:

Pilot: 1LT Donald M. Murray, FAG memorial No. 187425766.
Co-pilot: 2LT Robert M. McGraw, FAG memorial No. 187425821.
Navigator: 2LT William R. Meyer, FAG memorial No. 187425881.
Bombardier: 2LT Chester R. Gwinn, Jr., FAG memorial No. 56247418 .
Engineer/top turret gunner: TSGT Michael F. Curtin, FAG memorial No. 187426086.
Radio operator: TSGT Rogers W. Tatum, FAG memorial No. 187426086.
Ball turret gunner: SSG Alexander C.J. Robert, Jr., FAG memorial No. 187426036.
Waist gunner: SSG Carl G. Moak, FAG memorial No. 110271738.
Waist gunner: SSG Frank M. Wininger, FAG memorial No. 56295651.
Tail gunner: SSG John W. Rogers, FAG memorial No. 56293851.
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Entered the service from Colorado.