DRAFT: The Rad Lab at MIT

Joseph E. Riehle of Cincinnati and an Unusual Contribution to Allied Victory in World War II

The Radiation Laboratory, also called the Rad Lab, was a radar research laboratory located at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts (US). It was first created in October 1940 and operated until 31 December 1945 when its functions were disbursed to industry and peace time research facilities.

The use of microwaves for various radio and radar uses was highly desired before the war, but existing microwave devices were far too low powered to be useful. Alfred Lee Loomis, a millionaire and physicist who headed his own private laboratory, organized the Microwave Committee to consider these devices and look for improvements. In early 1940, Winston Churchill organized what became the Tizard Mission to introduce US researchers to several new technologies the UK had been developing. Among these was the cavity magnetron, a leap forward in the creation of microwaves that made them practical for the first time.

MIT “Radiation Lab” c.1944

Loomis arranged for funding under the National Defense Research Committee (NDRC) and reorganized the Microwave Committee at MIT to study the magnetron and radar technology in general. Lee A. DuBridge served as the Rad Lab director. The lab rapidly expanded, and within months was larger than the UK’s efforts which had been running for several years by this point. By 1943 the lab began to deliver a stream of ever-improved devices, which could be produced in huge numbers by the US’s industrial base. At its peak, the Rad Lab employed 4,000 at MIT and several other labs around the world, and designed half of all the radar systems used during the war.

Alternative / for consolidation:

In June of 1940, President Franklin Roosevelt approved the creation of the National Defense Research Committee (NDRC) at the urging of several scientists and academics.  Alfred Lee Loomis, a millionaire retired from Wall St. and operating a private research facility near New York at the time, was heavily into research into the practical applications of microwave radiation and, accordingly, was appointed to head up the Microwave Committee of the NDRC at MIT near Boston.  Loomis was the Nephew of Henry Stimson, the Secretary of Defense and had equally strong connections in financial and scientific circles.  Loomis’ team and other radar researchers around the world recognized that their work with under powered, longer wavelength radar devices was problematic. In September 1940, under the bombardment from the Battle of Britain, the British sent Sir Henry Tizard to the US to pursue the establishment of a joint research facility as agreed upon by Sir a Winston Churchill and President Roosevelt.  The Tizard mission disclosed the top secret development and provided a working prototype of the cavity magnetron which made ten-centimeter wavelength radar a reality. Developed earlier that year, this device, the size of a dinner plate, could be carried on aircraft and the short wavelength allowed for a smaller antenna, again more suitable for mounting on aircraft. The short wavelength and high power made it very effective at spotting submarines and even smaller objects from the air. 
In November of that year, the MIT research facility began operations.  Named the “Radiation Laboratory” or “Rad Lab”, an intentionally misleading name suggesting theoretical work on nuclear radiation, the facility was charged primarily with improving the magnetron, developing it for various specific applications and overseeing the ramp-up of production for the war effort.  
The Rad Lab would eventually employ nearly 4000 people. While employing large numbers of PhDs, the lab also employed many engineers and technicians. Joe Riehle was an experienced machinist, having worked for The Riehle Machine Company, owned by his father (Albert Joseph), for several years.  He had taken college level engineering courses in Cincinnati and continued to do so in Boston at Northeastern University.  (60 years later his grandson would earn a PhD at Northeastern).

Joseph Riehle heard about the formation and hiring at the lab in 1942 from a friend, William Sheeran, who had heard only superficial information about a secret government facility that needed engineering and technology expertise. He pursued the lead and and began work …

Riehle’s initial role at the Rad Lab was involved in… During this period Joe and Martha’s first son, Bill, was born.

In [Month, year] Riehle was drafted into the army and sent to basic training in the midwest with his wife [and new born son] returning to Cincinnati. He had been told by his superiors at the Lab that they intended to have him released from the army and returned to the Lab but years later he recalled thinking that nobody was getting out of the army until the anticipated D-Day operation was successfully accomplished.

Nonetheless he was called to the base commander’s office, wondering what the heck was he in trouble for now, and was told, in effect, “son, I don’t know who you know but you’re out of this arm, you’re going back to Boston”.

I have often imagined that moment, realizing suddenly that instead of facing possible dath on the beaches of France he would be reunited with his wife and son to do a job he enjoyed while contributing significantly to the war effort. The only comment I can recall relating to that moment however was, in effect, “you never know when hard work and commitment to your assigned task will payback beyond any possible expectation.”

Second stint in Boston – role.

Release and return

Wright Patterson AFB

As a young boy in the 50’s, steeped in the drama of the recent World War, it seemed somehow disappointing that my father had not fought the bad guys, meaning of course that he did not carry a rifle in Europe or the Pacific. Still I understood that he had served, and that he served in an important, if not senior capacity. Over the years I realized increasingly how vital that contribution was, and how fortunate we were that he could serve in that capacity.

“Vital”, because by the time his friends and fellows from the “Greatest Generation” waded ashore in Normandy, the German Luftwaffe and U-Boat force were largely neutralized, in large part as a result of the work done at the Rab Lab. Similar benefits were of course realized at Saipan, Iwo Jima, Okinawa and elsewhere in the Pacific. “Fortunate”, because he, unlike many others from that generation, survived the war. Of course his 5 sons, 21 grand children and more than double that many great-grandchildren, most of whom might not be here otherwise, share in that good fortune.

Joseph died in 1983 at age 64 of coronary heart disease. His widow, Martha (LeSaint) Riehle survives as of this date in 2021 at 102 years of age.

Joseph was the son of Albert J. Riehle, grandson of Francis A. Riehle and great-grandson of Clemens Riehle who came to America from Baden, Germany in 1854.

Notes & Best Estimates for further edits:
– Employment card below, issued August 1943, suggest approximate start date
– Letter re draft suggest possible draft date soon after March 1944 with a brief delay before being sent back

Read March 1943 Letter Re. Draft Deferment


  • Conant, Jennet (2002). Tuxedo Park. New York, NY: Simon & Schuster. ISBN 0-684-87287-0
    Subtitle: “A Wall Street Tycoon and the Secret Palace of Science That Changed the Course of World War II
  • “MIT Radiation Laboratory” Wikipedia – Nov. 2020
  • Letter re. draft deferment and payroll related employment card provided by William Riehle from the papers of Martha Riehle.

Any additional papers or information related to J.E.
Riehle’s services at the Rad Lab would be greatly appreciated.
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