Aeronautical Instruments & Tools
USAAF Type E-6B Dead Reckoning Computer
The E-6B was developed in the United States by Naval Lt. Philip Dalton (1903–1941) in the late 1930s. The name comes from its original part number for the U. S Army Air Corps, before its reorganisation in June 1941. The designation "E-6B" was officially marked on the device for only a couple of years as by 1943 the Army and Navy changed the marking to their joint standard, the AN-C-74 (Army/Navy Computer 74). A year or so later it was changed to AN-5835, and then in 1948 to AN-5834.. Despite the name changes navigators and most instruction manuals continued using the original E-6B, whilst many just called it the "Dalton Dead Reckoning Computer".
This example is marked Spec no 94-27892 and order no 42-18252, confirming it was manufactured in 1942. The fact it has turned up here in the UK would seem to indicate it served with the USAAF in WWII. They were used for pre-flight planning and in the air to aid in calculating fuel burn, wind correction and route timings. This example is incomplete and has at some stage been separated from the back section, that would have been used to calculate the effects of wind and drift during flight;this is reflected in our price. Otherwise it is in generally good condition, with some patination due to age and use and is U. S. Army Air Forces property marked. Measures 5.5"x 4.5" (14 cm x 12 cm)