John G. Trump


John George Trump was an American electrical engineer and professor at MIT. He developed high-voltage generators for cancer treatment, led radar deployment during World War II, and organized one of the first venture-funded companies, a particle accelerator manufacturer. He was the paternal uncle of President Donald Trump.
Trump earned his PhD in 1933 as Robert Van de Graaff's first student, working on the design and insulation of electrostatic generators. He joined MIT's faculty and first applied these generators to cancer radiotherapy, building compact X-ray machines for hospitals. Over a 37-year career, he developed new therapy techniques, oversaw treatment of 10,000 cancer patients, and taught hundreds of radiologists. Trump directed the High Voltage Research Laboratory from 1946 to 1980, which explored uses of electrostatic machinery in medical sterilization, spacecraft propulsion, wastewater disinfection, and power transmission.
In October 1940, he joined Vannevar Bush's new National Defense Research Committee as a technical aide and helped establish MIT's Radiation Laboratory, which invented and manufactured radar sets for Allied forces. As the lab's assistant director and secretary of the NDRC Microwave Committee, he administered contracts for the war's largest civilian research enterprise. In 1944, he was sent to England and France to direct the lab's field laboratory, where he organized radar deployments for the D-Day invasion, worked on V-1 rocket interception, and advised American commanders on radar use in combat.
In 1946, Trump organized the High Voltage Engineering Corporation with co-founders Van de Graaff and Denis Robinson. HVEC was one of the first two startups backed by the American Research & Development Corporation, the first modern venture capital firm. Originally building compact accelerators for cancer clinics, HVEC pivoted to research accelerators as federal funding for nuclear physics expanded. By 1970, nearly 70 percent of experimental nuclear physics papers relied on data from HVEC accelerators. After his 23-year term as chairman ended, Trump offered technical advice as the company diversified into accelerator-enabled industrial products.
President Reagan awarded Trump the National Medal of Science in 1983 for the "beneficial application of ionizing radiation to medicine, industry and atomic physics." He received wartime commendations from President Truman and King George VI. Trump installed the original Van de Graaff generator at the Boston Museum of Science, and many HVEC accelerators remain in use at physics laboratories worldwide.

Early life and education

New York years (1907–1931)

Born in the Bronx, New York City, on August 21, 1907, John Trump was the youngest of three children born to German immigrants Frederick and Elizabeth Christ Trump. When the Queensboro Bridge was finished in 1910, the family moved to Queens, eventually settling in the Woodhaven neighborhood. When Trump was 11, his father died in the 1918 influenza pandemic, leaving his mother to support the family.
Like his siblings, Trump attended Richmond Hill High School, where he was a gifted student. He joined Western Electric's Manhattan engineering office in 1923, two years before it became known as Bell Labs.
Both John Trump and his older brother Fred joined their family's real estate firm. Their mother hoped that Fred would build homes and John design them. With support from his brother, John enrolled at Brooklyn Polytechnic Institute to study architecture. The brothers' work together ended due to differences in business philosophy: Fred preferred to sell units as they were planned; John thought they should only sell once constructed. By the end of his freshman year, John left the family real estate business and switched his concentration from architecture to engineering.
Selected as Brooklyn Poly's valedictorian, Trump graduated from in 1929 with a bachelor's degree in electrical engineering. While teaching electrical engineering at his alma mater, he earned his master's degree in physics from Columbia University in 1931.

MIT doctorate (1931–1933)

In fall 1931, Trump arrived at the Massachusetts Institute of Technology to pursue a PhD in electrical engineering. MIT's new president, the physicist Karl T. Compton, was recruiting scientists to strengthen basic research at the institute. Vannevar Bush, dean of MIT's engineering school, recommended Trump work with one of these recruits: Robert J. Van de Graaff, a 29-year-old physicist developing his electrostatic generator. Van de Graaff became Trump's advisor and lifelong collaborator.
Eager to artificially split the atom, Van de Graaff sought to build a model with sufficiently strong insulation to reach ten megavolts. He split his research between open-air models, which required large terminals, and vacuum-insulated designs, which were compact but technically challenging. In November 1933, he demonstrated the Round Hill generator, a air-insulated generator that produced dramatic electrical arcs and attracted broad press coverage. But the demonstration also revealed the design's fundamental limitation: high voltages broke down in open air.
To overcome these limits, Trump worked on vacuum techniques. He designed a synchronous alternating-current motor to power a vacuum, which proved highly efficient. Encouraged by this practical innovation, his dissertation also proposed a method to build vacuum-insulated, long-distance transmission lines for high-voltage direct current. In 1932, Van de Graaff filed to patent components in the transmission system. The new Tennessee Valley Authority showed interest in developing these patents for its hydropower projects, and Vannevar Bush offered to license them to the TVA by assigning them to the Research Corporation. Though the transmission project fell through, MIT became the first private university with a policy of research commercialization, and its arrangement was an influential predecessor to university patent licensing.
Trump received his doctorate of electrical engineering in 1933. His thesis, Vacuum Electrostatic Engineering, described these contributions and examined the factors governing voltage-insulation strength in vacuums.

Early career

After graduating, Trump remained at MIT as a research associate, then became an assistant professor in 1936. His research focused on improving high-voltage generators and finding new uses for them in industry.
While writing his thesis, Trump had learned about an MIT lecture on medical uses of high-voltage x-rays. At the time, low-voltage radiotherapy techniques could only target superficial tissues and required long exposures that damaged skin. Because Van de Graaff sources produced steady, controllable, power that other high-voltage sources could not, Trump hypothesized that they could produce penetrating, precise x-rays that could target deeper tumors.
In May 1935, Trump showed that striking a gold target with the Van de Graaff electron beam produced abundant x-rays. The Godfrey M. Hyams Trust funded the construction of a 1-MV generator for Harvard's Huntington Memorial Hospital, which entered service in March 1937. The first of several hospital generators Trump would build, it required a room-sized voltage terminal with an internal focusing coil suspended over the patient in the room below. Though just one-third the height of the Round Hill generator, its operators saw it as "magnificent monster." Radiologist reported that it provided "increased depth dosages, greater skin sparing, and greater intensity" than radium exposure, then the prevailing technique. The first patient treated by the Huntington machine survived beyond four years. However, Huntington Hospital survived only another four years, and the machine was shut down in 1941.
Trump focused his research on making hospital generators smaller and more controllable. He adopted a pressurized gas system developed by Raymond Herb, which allowed him to increase dielectric strength at a smaller size. He built a compact 1.25-MV generator for Massachusetts General Hospital in 1940, which treated patients for sixteen years. He built another generator for the Philadelphia Oncologic Hospital. Trump's pre-war generator installations have been acknowledged as precursors to the field of radiosurgery.
Trump's gas-insulated generator would find other commercial applications. With World War II engulfing Europe and Asia, the United States began expanding its military fleet production. With engineers at Boston Navy Yard, Trump discovered that his high-voltage x-ray generator could detect manufacturing defects in ships and aircraft. Robert Van de Graaff would carry this work forward through MIT's High Voltage Radiographic Project, a Navy-funded effort to build Van de Graaff generators to find ship manufacturing defects.

World War II service

Administration of the MIT Rad Lab (1940–1943)

During World War II, Trump interrupted his research on x-ray therapy to focus on military uses of microwave radar. In early 1940, Vannevar Bush organized the National Defense Research Committee to direct the White House's wartime research strategy. Trump joined the NDRC as technical aide to MIT President Karl Compton, head of the committee's radar and detection section. In October 1940, British scientists demonstrated secret microwave transmitters to the United States, offering vast potential improvements in resolution and range. NDRC members pressed Compton to organize radar research at MIT. On October 24, Trump joined the first meeting of Radiation Laboratory, where a small group identified space at MIT and submitted a funding proposal to the NDRC. Within a week, the Rad Lab began recruiting top physicists and engineers from universities across the country.
The Rad Lab focused on conceptual radar research in its first year. As an NDRC aide, Trump oversaw the lab's federal contract. The Pearl Harbor attacks pushed the Rad Lab into radar equipment production, and its rapid expansion pulled Trump inside the Lab's business operations. In March 1942, the lab reorganized around its expanded duties, and lab director Lee DuBridge appointed Trump to the lab's newly formed Steering Committee. A month later, Trump was appointed secretary of the NDRC Microwave Committee, overseeing all government radar research contracts.
During Trump's tenure in the Rad Lab's top administration, it would grow to become the war's largest civilian research contractor. It employed 3,879 personnel, constructed three buildings on the MIT campus, opened field operations around the world, and fulfilled $110,758,000 in government research contracts, or 80 percent of United States' radar research budget. The lab introduced new capabilities including early warning systems, fire control, and bombing through cloud cover, giving American forces a growing technological edge.

Review of Tesla papers

Following the death of Nikola Tesla in January 1943, the U.S. Office of Alien Property Custodian requested Trump's support to examine the notes, papers, and artifacts left by the inventor. Tesla had offered the U.S. Army a license to unspecified secret weapons, and officials believed his belongings might contain designs for a promised high-voltage "death ray." Tesla had bequeathed the items to his nephew, a Yugoslavian government official. OAPC was reluctant to send them to a Nazi-occupied country without prior review.
Then a government employee, Trump was called upon for his expertise in direct-current electrical equipment, which overlapped Tesla's work. After a three-day investigation in Manhattan, Trump reported in a classified memo to OAPC that the materials had neither military value to the United States nor would "constitute a hazard in unfriendly hands." In the memo, Trump expressed admiration for Tesla's well-known inventions, but assessed that his late-career ideas were "somewhat promotional" and "did not include new sound workable principles or methods."
After many of these personal items disappeared, the Federal Bureau of Investigation received letters accusing it of suppressing Tesla's design for a secret weapon. In 1984, technical papers describing the weapon were discovered at Yugoslavia's Nikola Tesla Museum and did not overturn Trump's assessment.

Service in Europe (1944–1945)

Late in 1943, the NDRC established the British Branch of the Rad Lab to coordinate plans for the invasion of Europe. In February 1944, Trump was appointed director of the BBRL. Initially asked to spend three months overseas, he would stay fifteen months in Europe from D-Day planning until the fall of Berlin. Trump oversaw the BBRL's expansion into a 100-member group with service operations in Malvern, Worcestershire, England, home of the British Telecommunications Research Establishment.
Stationed in Malvern, Trump was one of the few civilians read into secret D-Day plans. During preparatory meetings, Trump counseled generals and advised an overhaul of U.S. Army Air Force bombing tactics. He recommended radar techniques for radar-guided blind bombing ahead of the Normandy landings, enabling an assault of Nazi fortifications on the beachfront while avoiding the Allied troop carriers positioned just offshore. He also promoted the development of close air support with new Rad Lab ground-to-air SCR-584 radar sets.
Trump's BBRL oversaw the debut of long-range Microwave Early Warning radar used for monitoring and ground control of aircraft formations. MEW radar would be first activated on D-Day, where it documented from England the parachute drops and aerial bombings ahead of the Normandy troop landings. When Germany launched unmanned V-1 flying bombs against England in the week after D-Day, BBRL diverted MEW to detect the rockets at 130 miles offshore. Working with interceptor planes, and later with the Rad Lab's gun-laying radar, the V-1 attacks on England were suppressed by August.
After D-Day, Trump traversed the frontlines of the continental war. In August 1944, he followed Allied combat infantry into France. He arrived in Paris on the final day of its liberation, where he established the "Advanced Service Base" of the BBRL to support frontline operations. In November 1944, he was formally appointed to the Advisory Specialist Group, civilian scientists counseling USAAF General Carl Spaatz on navigational radar, precision bombing, and countermeasures against German radar. As troops advanced into Belgium and Germany, Trump would routinely meet with General Spaatz, and occasionally with other generals like George Patton and Pete Quesada. Radar historian Henry Guerlac described Trump as "one of the most respected and influential scientific figures in the entire theater."
During his final month in Europe, Trump conducted debriefing interviews with the leadership of Telefunken, the telecommunications firm that developed Nazi radar and countermeasures. From these interviews, he determined that German radar development had fallen substantially behind British and American war efforts. Trump attributed this to the failure of German military leaders to closely cooperate with scientists and industry experts, as Allied forces had.
Returning from Europe in April 1945, Trump led the Rad Lab's new Field Service division, an effort to reproduce the BBRL model in other theaters of combat. He helped the Rad Lab fulfill General MacArthur's request for a field operation in Manila. Efforts to formalize the operation ended abruptly with Japan's surrender.
Trump received recognition for his war service from both the United States and the United Kingdom. In 1947, King George VI awarded Trump the Medal for Service in the Cause of Freedom for his work on radar for the U.S. Air Forces and co-operation with Britain. A year later, President Truman awarded Trump Certificate of Merit, given to 250 civilian scientists who "performed a meritorious act or service" during the war.

Post-war career

After the war, Trump returned to his prior research in improving high-voltage generators, treating cancer, and began pursuing new applications of the artificial radiation. He pursued these both through research at MIT and a new company he organized, the High Voltage Engineering Corporation.

MIT cancer research

Trump returned to MIT and was appointed director of High Voltage Research Laboratory, a lab pursuing the improvement and application of electrostatic energy. Building upon his pre-war collaboration with hospitals, Trump focused on applying high-voltage engineering to medical challenges, particularly cancer treatment.
Months after the war ended, Trump began work with his Huntington colleagues to treat cancer patients at a new clinic building on MIT's campus. Having discovered a way to reach deep-seated tumors without harming tissues above them, he worked on methods to improve targeting. Trump designed an apparatus to rotate the patient around the beam, allowing x-rays to be cross-fired at the tumor site. This technique, known as "rotational radiation therapy," remains widely used.
In 1949, Trump began a two-decade collaboration with the Lahey Clinic, Boston's leading cancer hospital. Over the next 22 years, over 500 cancer patients a year received treatment at MIT using Trump's x-ray generator. Trump supervised treatments, improved targeting techniques, and personally trained many doctors in their use. For many years, he taught radiation physics to early-career doctors. The lab also focused on skin cancer treatment, designing a 5-MV electron-beam generator for targeting superficial lesions.
Despite advances in supervoltage generators, few hospitals had machinery to allow high-voltage cancer treatment by the 1940s. After receiving many requests from hospitals for his generator, Trump oversaw a commercialization effort to meet demand. He designed a compact, low-cost 2-MV Van de Graaff generator, then founded a firm to build them. Between 1948 and 1969, the High Voltage Engineering Corporation manufactured 43 of these 2-MV machines, which treated as many as 1,000 patients a day in the United States alone.
By the time Trump was appointed full professor in 1952, his cancer research devices had received worldwide attention. He attracted support from the National Institutes of Health and the National Science Foundation, each of which were building major cancer research operations. His 1960 Lamme Medal citation, given for contributions to electrical engineering, observed that Trump had also "remain faithful to his original goals in the treatment of malignant diseases." In 1963, Trump was appointed to the board of the Lahey Clinic, and became its chair after retiring his professorship in 1973. Throughout this period, he published widely in radiology and scientific instrument journals.

High Voltage Engineering Corporation

In 1946, Trump received more hospital inquiries about his Van de Graaff generators and decided a company could better meet demand. He approached MIT President Karl Compton, who had recently co-founded the American Research and Development Corporation, the first modern venture capital fund, who introduced Trump to ARD president Georges Doriot. Trump organized High Voltage Engineering Corporation with Van de Graaff and British physicist Denis M. Robinson as co-founders, whom he had met through wartime radar work. ARD provided $200,000 in initial capital, Compton arranged an exclusive license to MIT's Van de Graaff patents, and both served on HVEC's board. Trump served as HVEC's founding chairman and technical director while maintaining his MIT professorship.
Trump's motivations—making radiation therapy affordable to patients and accessible to hospitals—set the company's early production priorities. HVEC's first product was a commercial version of Trump's compact 2 MV generator, which could be operated by hospital technicians. It provided controllable, directed radiation that reduced damage to healthy tissue compared to traditional radium sources. Between 1948 and 1969, HVEC delivered these machines to 35 U.S. hospitals and eight hospitals abroad.
Trump's High Voltage Research Laboratory at MIT maintained close ties with HVEC. The laboratory provided technical feedback, developed clinical procedures, and tested prototypes for the company. While HVEC's Van de Graaff accelerators were early market leaders in radiotherapy, cheaper cobalt-60 machines and higher-voltage medical linear accelerators debuted in the 1950s, displacing HVEC's Van de Graaff accelerators as the preferred source for radiotherapy.
As federal funding for nuclear physics expanded, HVEC pivoted from medical devices to large research accelerators for universities and national laboratories. Trump and Van de Graaff contributed technical innovations that enabled higher-voltage machines. Between 1958 and 1973, HVEC manufactured 55 tandem accelerators that became the dominant platform for nuclear physics experiments. At its peak, nearly 70 percent of papers in experimental nuclear physics relied on data from HVEC accelerators.
Through declining federal support for nuclear physics, HVEC's research accelerator business collapsed. Trump exited his position as chairman in 1970, but continued providing technical advice over the next decade. The company reorganized as a conglomerate focused on industrial radiation processing products. Under this revised business model, Trump championed industrial and environmental uses of electron beam technology. In 1962, he encouraged the company to invest in new industrial applications of ionizing radiation. In the late 1970s, he led research into electron beam treatment of wastewater and sewage sludge, demonstrating that high-energy radiation could eliminate pathogens and organic contaminants. In 1980, HVEC received contracts from Miami-Dade County and the Massachusetts Metropolitan District Commission to develop commercial-scale water treatment systems.
Along with Tracerlab, HVEC was one of the first two new companies backed by ARD. At the time of its 1963 public offering, HVEC was ARD's largest asset and first major success, helping establish the viability of venture capital investing ahead of the debut of Digital Equipment Corporation. HVEC was privately purchased in 1988 and filed for bankruptcy in 2005. Trump held HVEC shares until his death in 1985.

Wastewater experiments

In 1972, Congress passed new Clean Water Act standards for secondary treatment of wastewater discharged into oceans and waterways. New rules gave cities five years to make major upgrades to sewage treatment. Trump, who had longstanding interests in sterilization methods, initiated a new program at MIT concentrated on disinfecting wastewater. He researched using an electron beam from a 2-MeV accelerator as the deactivating agent in the treatment of municipal wastewater sludge. The High Voltage Research Laboratory developed a prototype system that was tested at Boston's Deer Island Waste Water Treatment Plant, and it was able to provide bacterial and viral disinfection via continuous on-line treatment.
Trump retired from his faculty appointment in 1973, but continued running wastewater experiments and teaching MIT students as a senior lecturer. He directed the High Voltage Research Laboratory until stepping down in 1980. Trump remained engaged in wastewater research until the year of his death.
Trump died in Cambridge, Massachusetts on February 21, 1985.

Science education

Trump became a trustee of the Boston Museum of Science in 1961. When the museum installed the original Van de Graff generator as a permanent exhibition, he designed electrostatic shielding that allowed live audience demonstrations. He became a life trustee of the museum.

Legacy

President Ronald Reagan awarded Trump the National Medal of Science in 1983 for his innovative applications of radiation in medicine, industry and atomic physics. Trump died six days before the White House ceremony in February 1985, and his son John, Jr. accepted the medal on his behalf. In a posthumous tribute, the National Academy of Engineering described John Trump as "a pioneer in the scientific, engineering and medical applications of high voltage machinery."
In addition to his cancer research, Trump made institutional contributions to the Lahey Clinic. While chair of its board, he advocated for the relocation of the cancer clinic to a new hospital campus in Burlington, Massachusetts. The radiation oncology building of the Lahey Hospital & Medical Center is named for Trump. In 2024, one of his scientific collaborators endowed a fund at Lahey for diagnostic radiation named for Trump.

Disputed claims about career

Refusal to work on weaponry

James Melcher, Trump's successor as HVRL director, claimed that Trump declined to research military weaponry during his career. Melcher, an advocate for nuclear disarmament, stated: "John, over a period of three decades, would be approached by people of all sorts because he could make megavolt beams of ions and electrons – death rays... What did he do with it? Cancer research, sterilizing sludge out in Deer Island, all sorts of wondrous things. He didn't touch the weapons stuff." Trump worked on cancer research, sludge sterilization and also worked on military contracts for dual uses of microwave radar and high-voltage generators.

Longest-serving MIT professor

President Donald Trump has repeatedly claimed his uncle was MIT's "longest serving professor." John Trump served as an MIT professor for 37 years, retiring at the university's then-mandatory retirement age of 65. His career at MIT spanned 51 years, including research staff and senior lecturer appointments before and after his professorship. According to Newsweek, other MIT professors have had longer tenures: Doc Edgerton remained active at MIT for nearly 62 years, and Gilbert Strang served as professor for 61 years

Alleged connections to Unabomber

At a July 2025 political rally, President Trump asserted that domestic terrorist Ted Kaczynski was a student of his uncle and described asking about Kaczynski's performance as a student. The reclusive Kaczynski was identified as the Unabomber in 1996, nine years after John Trump's death, and multiple media outlets concluded it was unlikely President Trump knew the Unabomber's identity during his uncle's lifetime. Kaczynski was a student at Harvard University and the University of Michigan ; MIT officials told CNN they have no records of Kaczynski's enrollment in MIT courses.

Degrees

John has two degrees in physics and electrical engineering.

Personal life

John G. Trump was a member of the Trump family.
In 1935, he married Elora Sauerbrun, a fellow native of New York's Jamaica neighborhood. The Trumps had three children: John Gordon Trump of Watertown, Massachusetts; Christine Philp of New London, New Hampshire; and Karen Ingraham of Los Alamos, New Mexico; and six grandchildren.
The Trumps lived in Winchester, Massachusetts, and were members of the Winchester Unitarian Society.

Awards and honors

Trump received a number of awards including:

Selected publications

Trump wrote about 100 peer-reviewed articles, published across journals in applied physics, nuclear science, radiology and medicine, scientific instruments, and environmental engineering.

Essays

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Reports

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Manuscripts

A War Diary, 1944-5