Original Item: Only One Available. This a a very rare navigational instrument used on American bombers in WWII. The data plate on the transit chest reads:
U.S. ARMY AIR CORPS
TYPE NO. A-7 SERIAL No. AC-41-739
SPECIFICATION NO. 94-27747A
ORDER NO. AC-15814
MFR’S ASSY. DWG. NO. 3003-B
BENDIX AVIATION CORPORATION
PIONEER INSTRUMENT DIVISION
BENDIX, NEW JERSEY, U.S.A.
In January 1942 the Pioneer Instrument Division of Bendix Aviation received a contract worth $1,068,000 to make 2400 A-7 aircraft sextants for the Army Air Corps.
The A-7 was based on the instrument that Pioneer had introduced in 1931, but equipped with a finger activated pencil that enabled the navigator to make a number of vertical marks on a piece of roughened gray paper mounted below the index knob.
After each series of shots, these marks would be visually averaged, and the average time of the series determined from a stopwatch. Although the technique was relatively crude, the Army boasted that an experienced navigator using an in instrument of this sort could “set his plane down at the end of a transoceanic flight within an error radius of only 15 miles, less than four minutes’ flying time.
Offered in excellent condition.