 The Enola Gay ( Model number B @-@ 29 @-@ 45 @-@ MO , Serial number 44 @-@ <unk> , Victor number 82 ) was built by the Glenn L. Martin Company ( now Lockheed Martin ) at its Bellevue , Nebraska plant , located at what is now known as Offutt Air Force Base . The bomber was one of 15 B @-@ 29s with the " Silverplate " modifications necessary to deliver atomic weapons . These modifications included an extensively modified bomb bay with pneumatic doors and British bomb attachment and release systems , reversible pitch propellers that gave more braking power on landing , improved engines with fuel injection and better cooling , and the removal of protective armor and gun turrets . 
