When an aircraft was lost over enemy territory, a Missing Air Crew Report (MACR) was generated. A partial list of the MACRs for the 452nd Bomb Group is listed below. I used Ed Hinrichs's book Missing Planes of the 452nd Bomb Group as a source to reconstruct the missing page 206.
Of course, not all aircraft lost were over enemy territory. Many were lost during formation. Sometimes two aircraft would collide. Sometimes, a damaged plane could limp back to a friendly base. In addition, one or more crewmen would be killed, but the aircraft was not destroyed.
Images of the MACRs can be found at https://catalog.archives.gov/
Search for "missing air crew report number (number you are searching for)"
For example, search for "missing air crew report number 2520"
A list of service men from 452nd BG who died
This list was scanned from Missing Planes of the 452nd Bomb Group 3rd Edition, Compiled by Edward Hinrichs.
The book is available from Amazon: https://www.amazon.com/Missing-Planes-Groups-452nd-Group/dp/1412033217
KIA 452nd BG (pdf)
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