Homi Bhabha Asked the Tata Trust for a Physics Institute on 12 March 1944, Had the Apsara Reactor Critical by 4 August 1956, and Died on Mont Blanc on 24 January 1966 at 56

Homi Jehangir Bhabha, born on 30 October 1909, founded the Tata Institute of Fundamental Research (TIFR) in 1945, chaired India’s Atomic Energy Commission from 1948 and became the first secretary of the Department of Atomic Energy, created on 3 August 1954. The Bhabha Atomic Research Centre (BARC) says he set up the Atomic Energy Establishment, Trombay in January 1954, and that its Apsara reactor first reached criticality, the point where a chain reaction sustains itself, on 4 August 1956. He died at 56 on 24 January 1966 when Air India Flight 101 flew into the Mont Blanc massif.

Several parts of that record are argued over, and each is attributed below to the person who makes the claim. They are the date of his three-stage power plan, how Indian the Apsara reactor was, what he told Nehru and the public about building a bomb, and why the aircraft hit the mountain.

A letter to the Tata Trust on 12 March 1944

Bhabha was on a holiday visit to India when war broke out in Europe in 1939, and he could not return to Cambridge. In 1940 he joined the Indian Institute of Science in Bangalore as a reader in physics, in charge of a cosmic ray unit that the Sir Dorabji Tata Trust had set up for him, according to Virendra Singh of TIFR. The historian Jayita Sarkar writes that CV Raman, the Institute’s first Indian director, supported the appointment. Raman’s own discovery is covered in CV Raman and the effect that bears his name.

On 12 March 1944 Bhabha wrote formally to Sir Sorab Saklatvala, the Trust’s chairman, proposing an institute for fundamental research. Singh’s account is that the letter went to Saklatvala and not to JRD Tata. Tata had corresponded with Bhabha earlier, and Singh says his encouragement persuaded the Trust to back the plan. In the letter Bhabha expected nuclear power to be working “in say a couple of decades from now”, and wrote that India “will not have to look abroad for its experts but will find them ready at hand”. Hiroshima was still more than a year away, Singh notes. In April 1944, Sarkar adds, the Trust agreed to give one lakh rupees (100,000 rupees) a year to start a school of physics in Bombay.

TIFR says it was founded on 1 June 1945. It began inside the cosmic ray unit in Bangalore, moved to Bombay that October, and was inaugurated on 19 December 1945 at Kenilworth, a bungalow on Pedder Road, by the Governor of Bombay, Sir John Colville. Its founder director was Bhabha. In a speech at its new building on 15 January 1962 he called the institute “the cradle of our atomic energy programme”, Singh reports, and Singh adds that the commission’s physics division was first housed there and that Apsara’s control systems were built there.

Committee, commission, department

Singh records that an Atomic Energy Committee of the Council of Scientific and Industrial Research was formed towards the end of 1945 with Bhabha as chairman. On 26 April 1948 he sent Nehru a note on organising atomic research and recommended a commission. India adopted its Atomic Energy Act in April 1948, Sarkar writes, and named monazite, a thorium-bearing sand, and beryllium as priority raw materials whose export stayed embargoed.

The Department of Atomic Energy (DAE) says the Commission was first set up in August 1948 inside the Department of Scientific Research, which had been created that June. The Homi Bhabha Fellowships Council gives the day as 10 August. Singh names Bhabha as chairman and KS Krishnan and SS Bhatnagar as members. By mid-1949 a Rare Minerals Survey Unit existed, and Indian Rare Earths Limited was started in 1950 to process beach sands in Kerala and Orissa.

Sarkar notes that the pace drew criticism, with Meghnad Saha, then a member of the Rajya Sabha, asking why the commission had so little to show years after 1948.

The DAE was created on 3 August 1954 by presidential order, under the direct charge of the Prime Minister, with Bhabha as secretary. A presidential order avoided parliamentary scrutiny, Sarkar points out. A government resolution dated 1 March 1958, which Nehru laid before the Lok Sabha on 24 March, made the department’s secretary the commission’s chairman. Bhabha held both posts until his death, Sarkar says.

Trombay and the reactor named Apsara

Apsara was a one-megawatt swimming-pool reactor, meaning the fuel sits in a deep pool of water. In late 1954 the UK Atomic Energy Authority gave the department engineering drawings, technical data and six kilograms of enriched uranium fuel, Sarkar writes, and DAE engineers built it. BARC says Apsara reached criticality on 4 August 1956 and “was the first research reactor in Asia to achieve criticality”. Sarkar’s wording is narrower: the first operational reactor in Asia outside the Soviet Union.

Nehru formally opened the Trombay laboratories on 20 January 1957, Singh writes. Research reactors CIRUS and ZERLINA became critical in 1960 and 1961, and a plutonium plant was commissioned in 1964. BARC says Apsara was shut permanently in June 2009, and that its successor, Apsara-U, first approached criticality on 10 September 2018.

Chairing the Geneva conference of 1955

The first United Nations conference on the peaceful uses of atomic energy met in Geneva from 8 to 20 August 1955, and Bhabha presided. A State Department memorandum of 19 January 1955 says that Lewis Strauss, chairman of the US Atomic Energy Commission, had “expressed strong objections” to Bhabha as president, and judged it doubtful that Washington could stop the appointment. The memo asks whether Strauss would drop the objection if the US got its choice of secretary-general. A margin note reads “He did.”

Sarkar counts more than 1,400 delegates from 73 countries. In his opening speech Bhabha argued that developing countries needed atomic power. He also told delegates that nuclear power would put into many hands fissile material “from which the making of atomic bombs is but a relatively small step”.

David Fischer’s history of the International Atomic Energy Agency records another forecast from the chair. Bhabha predicted that “during the next two decades” scientists would find a way to release fusion energy in a controlled manner. Singh calls him “unduly optimistic” on fusion, and on 28 August 2026 the Press Information Bureau said that fusion is “still under development for commercial electricity generation”.

Fischer also records Bhabha’s stand in the talks that wrote the Agency’s statute. He opposed a clause letting it require deposit of surplus plutonium, arguing it would let “23 gentlemen in Vienna” dominate recipient states.

The three-stage plan as the DAE describes it

The Nuclear Power Corporation (NPCIL) and the Press Information Bureau describe the same sequence. In stage one, pressurised heavy water reactors burn natural uranium, using heavy water to slow the neutrons, and their spent fuel is reprocessed to recover plutonium. In stage two, fast breeder reactors run on that plutonium and breed uranium-233 from thorium. In stage three, reactors use uranium-233 and thorium as fuel.

The reason lies in the reserves. The Press Information Bureau says India’s uranium reserves are low grade and need supplementing by imports, while thorium is abundant in coastal sands from Kerala to Jharkhand. NPCIL’s table lists 78,000 tonnes of uranium and 363,000 tonnes of thorium.

Sources differ on dates. According to the Press Information Bureau, Bhabha proposed the programme in 1954. Sarkar cites a paper by Bhabha and NB Prasad at the second Geneva conference in 1958 as the place where he “laid out” the three stages. She also reads the plan as giving an official peaceful purpose to the plutonium from CIRUS, plutonium that could equally fuel weapons.

On 28 August 2026 the Press Information Bureau reported that the Prototype Fast Breeder Reactor at Kalpakkam reached first criticality in April 2026, which it called the start of stage two.

What he said about a bomb

In the excerpt from Bakhtiar Dadabhoy’s biography, Nehru asked Bhabha in 1960 whether he could develop a bomb. Bhabha said about a year, and Nehru replied, “Well, don’t do it until I tell you to.” George Perkovich, the excerpt says, notes that the claim was not based on facts and that a bomb could not have been made before 1963.

Sarkar writes that after 1962, the year of the border war with China, Bhabha publicly made exaggerated claims that India could explode a device within 12 to 18 months of a decision. Days after China’s first test, on 24 October 1964, he said in a broadcast on All India Radio that a stockpile of 50 atomic bombs would cost under Rs 10 crore (100 million rupees). A US embassy telegram of 21 January 1965, relaying a report by a Dr Wiesner to the US Atomic Energy Commission, says Bhabha was still saying 18 months, and adds that “Many of the scientists object to this optimistic figure.”

The Nuclear Weapon Archive, citing Raj Chengappa’s Weapons of Peace (2000), reports that Raja Ramanna later said Bhabha planned from the start to build a weapons capability. Stuart Leslie and Indira Chowdhury write that Bhabha “clearly designed Trombay with nuclear weapons as more than an afterthought”, while remaining ambivalent himself about a nuclear-armed India.

Air India 101 and the claims made since

Flight 101 left Bombay on 23 January 1966 for London, with stops at Delhi, Beirut and Geneva, according to the French final report. Singh writes that Bhabha was on his way to a meeting of the International Atomic Energy Agency in Vienna. The Boeing 707-437, registration VT-DMN, had 11 crew and 106 passengers on board. At about 07:02 universal time it hit the ridge near the Vallot refuge at roughly 4,750 metres (15,585 feet), in the commune of Chamonix. All 117 died.

France’s transport secretary set up a commission of inquiry on 27 January 1966, chaired by the air force engineer-general L Bonte. Accredited representatives of India, the United States, Switzerland and Italy took part and approved the report’s terms. It is dated 9 March 1967 and was printed in the Journal Officiel on 8 March 1968.

The commission found that the aircraft, engines and ground equipment were not at fault. One of two navigation radio receivers (VORs) was out of service when the aircraft left Beirut, which the rules permitted. Its most probable explanation was that the captain misjudged his position relative to Mont Blanc and told Geneva. The radar controller saw the error and gave information meant to correct it, but without precise phraseology the captain misunderstood. At 07:00:43 the captain said “we are passing abeam Mont Blanc now”. The controller replied, “you have five miles to the Mount Blanc”, and the report says the controller meant five miles still to go before the mountain. Earlier the controller had proposed that the captain keep descending in visual conditions, staying 1,000 feet above the cloud tops, and the captain accepted. Believing he had passed the ridge, he continued down. Also cited are a low sun, white-out, downdrafts of about 25 metres per second and possible altimeter errors of 800 to 1,100 feet.

A collision with another aircraft was proposed in the press after the crash. The report says pieces gathered at the site by journalists, which fed that idea, were identified by its investigators at Courmayeur on 9 March as parts of the Boeing, and that no other civil or military aircraft was reported missing that day. Gendarmes who reached engine parts on the ice soon after the crash found them hot at impact, which the report takes as proof the engines were running. Two pilots in the area saw a dark cloud rise near Mont Blanc between about 07:02 and 07:04, and the report treats it as a cloud that formed after the impact.

Later claims differ. The climber Daniel Roche, who found aircraft remains on the mountain in 2017, says the plane collided with an Italian aircraft, according to ThePrint in 2018. He told The Aviationist in 2009 that a crash into the mountain should have caused a huge fire. David Cenciotti of The Aviationist replied that evidence would have been found if a shoot-down had happened. ThePrint says a CIA story rests on an alleged conversation between the officer Robert Crowley and the writer Gregory Douglas, published in a 2008 book. Neither claim comes with a document in the French report or the other sources cited here. The flight recorder was never found, and the report says the debris could be examined only in part.

After Bhabha

Vikram Sarabhai succeeded him as commission chairman, according to the Nuclear Weapon Archive, which also says Bhabha set up a nuclear explosive design group on 5 April 1965 under Raja Ramanna and that Sarabhai halted it in June 1966. Sarkar’s account differs. She says the BARC explosions group had worked on underground explosions since November 1964, and that Sarabhai neither encouraged it nor ended it during his tenure from 1966 to 1971. Sarabhai’s own story is in Vikram Sarabhai and the birth of Indian space research.

BARC says AEET was renamed after Bhabha’s death, and the Nuclear Weapon Archive dates that to 12 January 1967.

On 28 August 2026 the Press Information Bureau put India’s nuclear fleet at 24 reactors with 8.78 GW of capacity, against a stated goal of 100 GW by 2047. India’s solar capacity gives the same 8.78 GW inside the country’s 308.03 GW of non-fossil capacity.