As Manhattan Hide and Wool continued to grow and move along, Jack received a draft notice in December of 1941.  Because the business needed him to get through the peak season, Jack requested to be deferred until January 31 of 1942 offering to voluntarily enlist if his request was granted.  The government agreed and after the fur season Jack got a call on February 2, 1942 to report to duty.  By February 3rd he was at Fort Leavenworth reporting for duty and was sworn in.  Jack would not return for 3 years while Sam and Marvin ran Manhattan Hide and Wool.

Jack was assigned to the US Army Air Forces, the 8th Air Force, 68th Bomb Squadron, 44th Bomb Group, 2nd Air Division as an Air Operations Specialist (or as Jack called it ‘amateur navigator’).  By October of 1942 Jack was already making bombing runs over the English Channel.