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Feature Article: The E-6B
The E-6B was more created than invented by Phillip Dalton
in the early 1930s. It was initially called "The Dalton
Dead reckoning Computer" . The exact derivation of E6B is
not known but the E-6B has become the generic name for a vast
number of similar devices, which include a circular slide rule
and a sliding wind angle ground speed plotter. The Dalton E-6B
was developed from a large shipboard device for handheld use
aboard aircraft. My first E-6B, which is still in the family,
is from WWII and made of solid brass with enameled engraving.
A quality piece. Plastic E-6Bs became common later in the war.
Aluminum and cardboard came later as the E-6B became obsolete
with the advent of electronic E6Bs.
E-6B
Dalton invented several flight computers before the design that
we all know so well, but they were NOT derived from a shipboard
device. (A much earlier - 1917 - very popular flight computer
was, however, so it's easy for people to think all F/Cs came
from marine usage. Some of the navigation principles are the
same, of course.)
His "Model J" was first bought in quantity by the
US Army Air Corps in very early 1940, I believe, and it was given
the designation of a navigation device "E" along with
the "-6B". Even though there was an "E-6A"
made, a very real possiblity is that the "6B" was arbitrarily
settled on because that was the British/Canadian/ Australian
prefix for aerial navigation devices. (e.g "6B/245"
for one example RAF flight computer)
Last Modified December 25, ©2025 TAGE.COM
