Alfred Lee Loomis (November 4, 1887 – August 11, 1975) was an American attorney, investment banker, philanthropist, scientist, physicist, inventor of the LORAN Long Range Navigation System and a lifelong patron of scientific research.

He established the Loomis Laboratory in Tuxedo Park, New York, and his role in the development of radar and the atomic bomb contributed to the Allied victory in World War II.

[1] He invented the Aberdeen Chronograph for measuring muzzle velocities,[2] contributed significantly (perhaps critically, according to Luis Alvarez[3]) to the development of a ground-controlled approach technology for aircraft, and participated in preliminary meetings of the Manhattan Project.

[citation needed] His first cousin was Henry Stimson, who held cabinet-level positions in the administrations of William Howard Taft, Herbert Hoover, Franklin Roosevelt, and Harry S. Truman.

At Aberdeen he met and worked with a Johns Hopkins physicist, Robert W. Wood, under whose influence Loomis's long-standing interest in inventing and gadgetry evolved into the serious pursuit of experimental and practical physics.

He and his small staff conducted pioneering studies in spectrometry, high-frequency sound and capillary waves, electro-encephalography, and the precise measurement of time, chronometry.

Loomis often sent first-class tickets to famous European scientists so that they could travel to the United States to meet with their peers and collaborate on projects.

At first, some in the scientific community called him an "eccentric dabbler," but soon his laboratory became the meeting place for some of the most accomplished scientists of the time, such as Albert Einstein, Werner Heisenberg, Niels Bohr, James Franck, and Enrico Fermi.

He turned this Tuxedo Park laboratory into a meeting place for the most visionary minds of the twentieth century; Albert Einstein, and the aforementioned scientists.

[12] Additionally, Loomis's 1937 house in Tuxedo Park by architect William Lescaze is regarded as an early experiment in double-skin facade construction.

[14] In the late 1930s, Loomis's scientific team turned their attention to radio detection studies, building a crude microwave radar which they deployed in the back of a van.

[16] On hearing that the British magnetron had a thousand times the output of the best American transmitter, Loomis invited its developers to Tuxedo Park.

He pressed for the development of radar in spite of the Army's initial skepticism, and arranged funding for the Rad Lab until federal money was allocated.

Meanwhile, Loomis assumed his customary function of eliminating the obstacles to research and providing the encouragement that was needed at a time when success still remained elusive.

The resulting 10-cm radar was a key technology that enabled the sinking of U-boats, spotted incoming German bombers for the British, and provided cover for the D-Day landing.

President Roosevelt lauded the value of Loomis's work, describing him as being the civilian who was second perhaps only to Churchill, in facilitating the Allied victory in World War II.

Loomis was married to Ellen Farnsworth for more than 30 years: beautiful, delicate and often suffered from debilitating depression, eventually developing dementia.

At this point he completely changed his lifestyle, eschewing his multiple residences and numerous servants and settling into a single household in which he and his wife shared a relationship that was characterized by its domesticity.