Description:

U.S. ARMY AIR FORCE BALL TURRET GUN SIGHT
Type K-4 Computing Gun Sight, approx. 12" x 13" x 9 1/2", as used in the underside bal turrets of B-17 and B-24 heavy bombers during World War II. The sight would be mounted suspended from the ceiling of the turret, with an optic head fitted with a glass screen positioned on the bottom of the instrument, in the gunner''s line of sight. An illuminated reticule would be projected onto this screen. The sight is fitted with dials allowing the gunner to input his target''s wingspan and range; the mechanical computer within the instrument would then automatically calculate and compensate for the lead angle. The back panel is fitted with a metal plaque listing the model number, the serial number "414110", and identifying the manufacturer as the N.C.R. Co. of Dayton, manufacturing the sight under license from the Sperry Gyroscope Co. The sight head is angled slightly off-center, easily adjusted, else very good.

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April 18, 2018 10:00 AM EDT
Elkton, MD, US

Alexander Historical Auctions LLC

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Bid Increments
From: To: Increments:
$0 $99 $10
$100 $499 $20
$500 $999 $50
$1,000 $1,999 $100
$2,000 $4,999 $250
$5,000 $9,999 $500
$10,000 $19,999 $1,000
$20,000 $49,999 $2,500
$50,000 $99,999 $5,000
$100,000 + $10,000