The Last Mission — Harry Mazer

In 1944, as World War II is  raging across Europe, fifteen-year-old Jack Raab  dreams of being a hero. Leaving New York City, his  family, and his boyhood behind, Jack uses a false  I.D. and lies his way into the U.S. Air  Force.

From their base in England, he and his crew  fly twenty-four treacherous bombing missions over  occupied Europe. The war is almost over and Hitler  near defeat when they fly their last mission -- a  mission destined for disaster. Shot down far  behind enemy lines, Jack is taken prisoner and sent to  a German POW camp, where his experiences are more  terrifying than anything he'd ever imagined.