330-PS-3157 :  Gypodyne Completes Coaxial ‘Copter Test Program for Navy.   The Navy Bureau of Aeronautics revealed that the gyrodyne coaxial helicopter, pictured here, has completed an extensive program involving flight testing to military specifications.  This is the first coaxial-type helicopter to complete such tests.  The coaxial helicopter was flown for a year under the Navy contract at the heliport of the Gyrodyne Company of America, Inc., St. James, Long Island, and the Navy is currently evaluating the test data acquired.  Results of the tests will be made available, according to the Bureau of Aeronautics officials, to such agencies as the Air Force, Army, and the National Advisory Committee for Aeronautics to permit evaluation for future coaxial helicopter designs, January 30, 1953.  (5/5/2015).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/127906254@N06">National Museum of the U.S. Navy</a>
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