Robert James Benninger was born on January 26, 1923, in Pittsburgh, Allegheny County, Pennsylvania. He was the son of Charles Curtis Benninger and Jane F Benninger. He served in the 369th Bomber Squadron, 306th Bomber Group, Heavy, as a First Lieutenant and a navigator of B17G (#42-31499) during World War II. On February 8, 1944, after completing a bombing mission over Frankfurt, Germany, his plane was shot down. Surviving the crash, 1Lt Benninger evaded capture with the help of local resistance fighters, who provided shelter and assistance as he awaited the opportunity to escape back to England.

Unfortunately, the safety of 1Lt Benninger and seven other American airmen was compromised after a betrayal by local collaborators. They were captured by German forces, along with two members of the Belgian resistance who had been aiding them. The Belgian resistance members were deported to camps in Germany, where they later died. On April 22, 1944, 1Lt Benninger and the other airmen were taken to a wooded area near Chimay, where they were executed by German troops and buried in a mass grave.

After the war, those responsible for the massacre were prosecuted by Belgian authorities. 1Lt Benninger is now buried in the Winchester National Cemetery, Winchester, Winchester City, Virginia, USA.