In 1935 the USAAC wanted to build a potential intercontinental bomber, a 'Guardian of the Hemisphere,' and granted Donald Douglas a contract to build the world's largest bomber.The groundwork for the intercontinental bomber had been laid in the previous two decades by the courageous military and civilian pilots who risked their lives to set new distance and endurance records. After World War I the future Axis and Allied nations built larger aircraft and finally dur...

The XB-40 and XB-41 were secret, little-known experimental modifications of the B-17F and B-24D, respectively, into heavily-armed bomber gunships sometimes referred to as “bomber escorters”.They were developed during early World War II in response to the lack of a USAAF long-range fighter aircraft able to escort and protect regular B-17 formations making the round trip from Britain deep into Germany. Unfortunately, these “protecters” were found wanting in several w...