A little bit more evidence (more where that came from).   All quotes are from 
CIA documents from 1952 released (after being declassified) to MUFON 
following a 
FOIA request.
CIA UFO summary dated 14 August 1952 entitled  FLYING SAUCERS
'In January 1948, an interception was attempted at Godman Field Kentucky and 
the 
pilot - Captain Mantell -crashed and was killed.  In October 1948, a National 
Guard fighter pilot at Fargo, North Dakota - Lt. Gorman - coming after dark 
spotted a moving light below him - also seen from the field - and for 
twentyminutes put on a dog-fight with it, finally, being outdistanced at 
17,000 
feet.  the third incident occurred in April 1949 at White Sands proving 
ground 
when a Navy Commander, tracking a missile flight by theodolite, watched two 
discs maneuvering at high speed around the test rocket.  three such sightings 
were made at White Sands within a month.'
'Reported characteristics include three general levels of speed:
hovering; moderate, as with conventional aircraft; and stupendous,
up to 10,000 miles per hour in the White Sands incident.  Violent
maneuvering was reported in somewhat less than 10%.  Accelerations have been 
given as high as 20 G's.'
'Second, a recent Far East report from an aircraft carrier operating
between southern Korea and Honshu.  here ships radar reported a high
speed target approaching from the north.  Observers on the bridge picked it 
up 
visually as a plane.  When still far out, it did a superspeed 180 deg. turn 
and 
shortly thereafter split in two, disappearing both visually and in PPI 
scopes.'
--- FMail 1.22
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