Telfer went up on a mission to Brux, CZ on July 21, 1944. He was in the "Jersey Bounce". The official story, from a crew member on the plane, on record is this:

 

After completing the bomb drop, a piece of flak hit the right side of the radio room hitting the hydrogen generator causing it to burst into flames. The pilot called for the ball turret gunner, William S. Telfer, to come up out of the ball turret as I yelled, "Fire!" There were flames in the radio room and heavy smoke as we tried to extinguish the fire. Telfer snapped on his chute, came over and got a "walk around" oxygen bottle from me. I plugged it into the filler valve. He walked over to the waist door, looked out for a few seconds and came back to return the oxygen bottle. He retraced his steps to the door and jumped. We saw his parachute open. We were deep into enemy territory.

 

A commander on the ground recorded the following:

 

S/Sgt William S. Telfer was captured July 21, 1944 near Leitmaritz and given to the Gestapo. According to a statement given by the military police, Telfer bailed out of his plane and, as far as it could be established, he suffered a broken leg, severe head and internal injuries and died from those injuries later that day. He was buried in a cemetery in Leitmaritz on July 29, 1944.

 

Further research revealed his body was disinterred, returned to this country, and he is buried out in CA with his parents.