Boeing B-17 Flying Fortress. WW IIs iconic four-engine heavy bomber. » Subscribe: » Visit the Official Site: .\r<br>\r<br>Copyright © 2012 Malcolm Auld This video and audio material may not be used in any form without written permission. The Boeing B-17 Flying Fortress was a .\r<br>\r<br>Documentary 2015,\r<br>\r<br>Fortress Of The Sky - The B-17 Bomber - The development of the Boeing B-17 Flying Fortress, a four-engine heavy bomber aircraft developed in the 1930s for .
