Elmer Edward Koepsell was born in South Dakota on May 2, 1911. His parents were William H. Koepsell (3 Nov 1886 – Feb 1969) and Lena August (Matzke) Koepsell (23 Feb 1886 – Jun 1980). He had one brother, Harvey Koepsell (13 Sep 1912 – 28 Jan 1998). He graduated from Canova, South Dakota, High School in 1929, and worked as a salesman for Standard Oil in the Canova area. He married Edna Mae Hanno at Hartford, Minnehaha County, South Dakota on April 25, 1939. They had one son, William Gale Koepsell. Sgt Koepsell's home of record was Canova, Miner County, South Dakota.

He enlisted in the U.S. Army in 1944, and completed Army Air Forces aerial gunnery training at Kingman, Arizona. He was then assigned as waist gunner on the heavy bomber crew of Lt Daniel C. Smoke Jr. The Smoke crew completed B-17 operational training at Biloxi, Mississippi, and was sent to Hunter Field, Savannah, Georgia, where they were assigned a new B-17 for the deployment to England. They were assigned to the 838th Bomb Squadron of the 487th Bomb Group at Army Air Forces Station 137 near Lavenham, Suffolk, England. They arrived at Station 137 by February 26, 1945, and became part of the 8th U.S. Army Air Force in Europe.

On March 19, 1945, the 487th Bomb Group dispatched thirty aircraft to bomb a communications center at Zwickau, Germany. The Smoke crew flew B-17G 43-38038 on this mission. Because of poor weather over England, the Group assembled into formation over A-71, the Allied advanced landing ground near Clastres in northeastern France. Sgt Koepsell and his eight crewmates were killed in action when their aircraft collided with Lt John R. Virgin's B-17G 43-37969 'Beverly Jean' during formation assembly. All of Lt Virgin's crew bailed out and survived, but none of Lt Smoke's crew was able to bail out. Sgt Koepsell and his crewmates perished in the subsequent crash of their aircraft near Couvron, France.

The dead were buried initially at the temporary U.S. Military Cemetery Champigneul #1 near Chalons-sur-Marne, France. (Chalons-sur-Marne was renamed Châlons-en-Champagne in 1998.) After the war, Sgt Koepsell's remains were reinterred at Epinal American Cemetery in France.

B-17G 43-38038 crew:
• Smoke Jr, Daniel C – 2/Lt – Pilot – KIA
• Pendarvis, George H – F/O – Copilot – KIA
• Olsen, Gunnar K – F/O – Navigator – KIA
• Strong, John H – 2/Lt – Bombardier – KIA
• White Jr, John – Sgt – Engineer – KIA
• Stone, Harold J – Sgt – Radio Operator – KIA
• Sala, David W – Sgt – Ball Turret Gunner – KIA
• Koepsell, Elmer E – Sgt – Waist Gunner – KIA
• Burres, Richard E – Sgt – Tail Gunner – KIA

Source of information: Paul M. Webber, www.findagrave.com, www.abmc.gov