the industry of aviation is planning a transition to the use of sustainable fuels for reduce the impact on global warming. As government agencies and airlines work hand in hand to develop biofuels, some wonder if there is a cleaner alternative. Nuclear energy has been the subject of study by some engineers and experts in the military industry for decades. A nuclear plane not only would it reduce the carbon footprint, but it would be able to operate 24/7.
While the idea of a jet-powered plane sounds good on paper, its implementation is more complex what it seems like. Years of studies and experiments by the United States and the USSR during the Cold War concluded that nuclear planes are impractical and dangerous. Issues such as radiation or the consequences of a possible plane crash prevented governments from adopting this energy source in the mid-20th century.
After decades of technological progress, the question of whether it would be possible to develop a round nuclear plane is again being raised. A report from the NATO Energy Security Center of Excellence studies whether it is possible to design a jet-powered aircraft today. This energy source, which powers submarines and warships, is considered vital in future military operations.
Would it be possible to exchange the engines of an Airbus A320 for small jets? To answer this question we first have to travel back in time.
A nuclear plane to power supersonic flights
Nuclear planes were part of the first ideas that man had after the discovery of fission in 1938. Prior to the space race, The United States and the Soviet Union competed for nearly a decade to develop a nuclear propulsion system that would be integrated into bomber and reconnaissance aircraft. The idea of an aircraft that did not have to be refueled would give a considerable advantage to whoever developed it first.
According to the document The Cold War competition for a nuclear-powered aircraftthe first to propose a nuclear aircraft was Henry Fermi, an Italian physicist who won the Nobel Prize for Physics in 1938 and was part of the Manhattan Project. In 1942, Fermi considered using nuclear power in aircraft, which led to the creation of the Nuclear Power Project for Aircraft Propulsion in 1946.
The US government has funded five years of research and development on possible nuclear aircraft projects. Later, in 1951, companies such as General Electric, Convair, Lockheed and Pratt & Whitney were invited to collaborate. The Atomic Energy Commission and the Air Force left it to private contractors to development of aircraft capable of flying with the help of a jet.
Around the same time, the Atomic Energy Commission and the Air Force focused their efforts on developing a nuclear turbojet engine. Known as CAMAL, the engine was to be fitted to an intercontinental bomber. A memorandum from the Commission anticipated that it would be possible to carry out routes of one or more round the world with a load of the reactor.
Radiation, the main enemy
The first nuclear aircraft experiments were conducted with two modified bombers carrying a test reactor. convair he took two B-36s and retrofitted them with a sealed cockpit that could hold three crew members and two engineers. The thick windows up to 30 centimeters thick were necessary to isolate a 1-megawatt reactor placed in the cargo bay.
Though the armor proved effective in protecting the crew, its design revealed a problem that would be inherent in nuclear aircraft. To avoid radiation contamination, components were needed that would add weight to the aircraft. The cabin of the NB-36H weighed 11 tons, added to the 16 tons of the test reactor. Another drawback would be the protection of the reactor in the event of an accident.
With Cold War tensions on the rise and the arrival of the first intercontinental missiles, the Government of The United States considered that it was not necessary to develop a nuclear aircraft and dismantled the Convair NB-36H in 1957. The Soviets had managed to put the first artificial satellite into orbit, so the efforts of the Americans were focused on the space race.
Interestingly, the nuclear aircraft program was officially canceled only in 1961. During these four years, the United States was aware of the Soviet Union’s experiments in jet-powered aircraft.
The Soviet Union and the Tupolevs nuclear
In 1952, Igor Kurchatov, the designer of the Soviet atomic bomb, began a program with other scientists to develop nuclear-powered bombers. master minds like Sergei Korolev, Andrei Tupolev, or Vladimir Myasishchev sketched the first prototypes. However, the program received approval once the Soviets learned that the American Convairs had made successful flights.
While the nuclear aircraft program was winding down in the United States, the USSR spent a lot of money producing its own version of the NB-36H. The Soviets developed the Lastochka, a Tupolev TU-95 modified to carry a nuclear reactor on board.
The Tu-95LAL had a pressurized cabin with a sensor to detect radiation. Behind it was a protective screen of lead and mixed materials. The reactor was installed in the cargo compartment, accompanied by a water-based cooling system. The Soviets installed multiple sensors in the fuselage to record radioactivity.
After several delays, the Tu-95LAL made its first flight during the summer of 1961. Like its American counterpart, the Soviet nuclear plane flew with a reactor, but only to prove that they could isolate the crew. The Lastochka made 40 test flights, most between May and August 1961.
The death of the nuclear program
American intelligence was aware of the development of the Soviet program, however, it ruled out that the USSR had built a nuclear plane.
There are indications that the Soviets have engaged in an effort to produce some kind of nuclear powered aircraft (NPA). We estimate that in 1960 the Soviets were able to fly a test aircraft with at least one nuclear power unit providing useful thrust during one phase of the flight, but there is no evidence that prototypes were actually built.
For their part, the Soviets mounted a propaganda campaign to mislead the Americans. Rodion Malinovsky, Minister of Defense and Marshal of the Soviet Union, proposed promote a legend about the invention of an airplane powered by a nuclear engine “with successful flight tests demonstrating the high technical performance of the reactor and its reliability”. Malinovsky and Pyotr Ivashutin, deputy chairman of the KGB, devised a disinformation campaign in late 1961.
Despite the propaganda and positive test flight results, the Soviets realized that developing a nuclear aircraft was expensive and the benefits did not justify the investment. The first intercontinental missiles were successful and there was no need to design a nuclear aircraft to carry out bombing tasks.
The Soviet nuclear aircraft program was canceled in 1961although the Tu-95LAL made an additional 6 flights between 1961 and 1965.
Why are there no nuclear planes today?
Although technology has advanced a lot compared to 1961, the idea of making nuclear aircraft has not crossed the minds of the military or scientists. The truth is that engineers face the same problems as sixty years ago. Designing a nuclear aircraft would involve considering an isolation system to prevent radioactive contamination.
The cabin would have to be sealed with materials such as steel, concrete, lead, cadmium or tungsten, which would add considerable weight to the aircraft. In addition to this, they must be considered cooling and emergency systems in case the reactor fails. Finally, protecting the reactor in case the plane suffers a damage would be the main limitation. A plane crash could turn into a catastrophe similar to Chernobyl, although to a lesser extent.
Although the engineers of Boeing or Airbus designed a nuclear plane capable of flying over the Earth several times, regulators would prevent its operation. Few governments would authorize jet-powered aircraft to fly, especially if they leave a trail of radioactive emissions along their flight path.