Wright Flyer
For many years the Smithsonian Institution did not formally recognize the 1903 "Wright Flyer" as first in flight. Instead, it proclaimed the Langley Aerodrome as first to be "capable" of manned powered flight. This policy offended the surviving Wright brother, Orville, who sent the "Wright Flyer" to the Science Museum in London on long-term loan, rather than donate it to the Smithsonian. In 1942 the Smithsonian publicly recanted its position, and Orville agreed to bring back the "Flyer".