John Vincent Atanasoff and Clifford Berry complete the Atanasoff Berry Computer (ABC), an unworkable prototype of the programmable digital computer.

Industrial applications of fluorescent lighting increase to such an extent that three times as many fluorescent bulbs are manufactured by the end of 1941 as in 1940.

Plutonium is isolated by Edwin M. McMillan and Glenn Theodore Seaborg.

Mar.

Nylon is first used to string tennis rackets.

Apr.

Under the direction of Lee DuBridge, Rad Lab physicists develop a workable prototype of the microwave AI-10 aircraft radar to detect both aircraft and submarines.

An executive order by President Roosevelt establishes the Office of Scientific Research and Development (OSRD), a larger federal agency that includes the NDRC, to oversee and coordinate all wartime research and development.

Aug.

The Rad Lab ASV (air-to-surface-vessel radar) detects ships twenty to thirty miles away and surfaced submarines two to five miles away.