John E. Parker was a Naval Academy graduate, and an entrepreneur. Parker was the president of Northwestern Aeronautical Corporation (NAC), which made wooden gliders for the war effort. Allied forces used the unpowered gliders at the Normandy D-Day invasion and at other battles to silently carry troops into enemy territory. The company assembled fifteen gliders a day in a huge plant on Minnehaha Avenue in St. Paul, Minnesota. After the War, Parker also became president of the newly created Engineering Research Associates (ERA), a computer development company.