1940 to 1949: Computing During World War II and the Postwar Era - The Technical and Social History of Software Engineering - page 62

Computers in the United States During World War II
Before addressing the developments of digital computers by the United States in
World War II, it is important to consider the analog computers used for bomb-
sights, naval gunnery, artillery ranging, and torpedo launches. There were only a
few digital computers built during World War II, but there were many thousands
of these sophisticated analog computers deployed on all surface ships, submarines,
and bombers.
One of the most interesting analog computers developed by the United States
during World War II is the famous Norden bombsight used on both Air Force and
Navy bombers. This bombsight had a very long service life—much longer than
the average digital computer. It continued to be used during the Korean War and
into the Vietnam War. The slang name for this bombsight by flight crews was “the
blue ox.”
Earlier bombsights could compensate for aircraft speed and direction but were
still not extremely accurate. They also required a lot of verbal communication
between the pilot and the bombardier during the final stages of the bombing run.
The Norden bombsight included a linkage to the aircraft's autopilot and actually
calculated the bomber's flight path on the final run before the bombardier would
release the bomb.
The Norden bombsight was developed by a Dutch engineer named Carl Norden
who moved to the United States and worked for the Sperry Gyroscope company.
However, he was also a consultant to the Navy, who awarded Norden a contract in
1929 to build a working automatic bombsight. Norden completed a working pro-
totype in 1930.
The Navy accepted the design, and production of the Norden bombsight started
in 1931. Norden founded his own company to build these bombsights and was
awarded a Navy contract. Later when the Army and Air Force wanted to buy the
Norden bombsights, they had to acquire them from the Navy, which caused in-
terservice rivalry.
Prior to the Norden bombsight, bombardiers also needed to use a variety of
tables and manually entered data into the bombsight while communicating course
directions to the pilot. As might be imagined, the process was sluggish and prone
to a variety of errors.
With the Norden bombsight, all of the calculations were handled by embedded
analog computers in the bombsight itself. The bombardier only had to make ad-