We visit the Air & Space (Smithsonian) Museum, DC; Udvar Hazy Museum, Dulles; National Museum of the Marine Corps, Triangle; and the Mid-Atlantic Aviation Museum (MAAM), Reading, PA. Also, the latter's annual WWII Weekend Airshow. Also, the ongoing restoration to flight of the first Air Force One: VC-121 "Columbine ". See MAAM's nearly airworthy P-61 Black Widow! Free days in DC.