Report: Russia's nuclear-powered 'Skyfall' missile is dirty and dangerous
NPR >
National Security
Report: Russia's nuclear-powered 'Skyfall' missile is dirty and dangerous
By Geoff Brumfiel, Connie Hanzhang Jin
Thursday, June 18, 2026 • 9:00 AM EDT
Heard on Morning Edition
Sometime on Oct. 21 of last year, high above the Arctic Circle, a lone missile shot skyward from a Russian island.<br>The missile flew northeast and then banked and began flying in loops for hours over the barren, frozen landscape.<br>According to Russian and Western sources, the new weapon, known in Russian as Burevestnik and by NATO as Skyfall, was powered by a small nuclear reactor. Few other details were forthcoming.
Related Story: NPR<br>Now, two MIT researchers have published an analysis that sheds fresh light on how the nuclear-powered missile actually worked. If they are correct, the October flight test marks the first time a nuclear-powered aircraft has ever flown. It would also suggest the opening of an extraordinarily dangerous new chapter in the 21st century's simmering arms race.<br>"This is something that is possible, but wildly expensive and very dangerous," said Jake Hecla, a professor at the Massachusetts Institute of Technology with a dual appointment in both aerospace and nuclear science and engineering, who led the new analysis along with co-author R. Scott Kemp.<br>Their modeling shows a reactor design that spews radiation as it flies, putting anyone living or working near the test site for the missile at "enormous risk, potentially."<br>The dream of nuclear flight
Since the 1950s, both the U.S. and the then-Soviet Union contemplated building nuclear-powered aircraft. Such weapons had the potential to give both sides an advantage in the Cold War because they would have nearly unlimited range. That could allow them to loiter near a target awaiting an attack order almost indefinitely, or they could attack from an unpredictable direction, making it harder to defend against.<br>In 1955, the U.S. Air Force put a small nuclear reactor inside a Convair B-36 strategic bomber to test whether it would expose the crew to excessive amounts of radiation in flight. The reactor was never hooked up to the plane's engines, but it did show that a nuclear reactor could fly. In 1961, the Soviet Union conducted similar experiments aboard a modified Tupolev TU-95 bomber.<br>Safety concerns left those concepts grounded, but the U.S. also worked on a series of nuclear reactors to power missiles. Known collectively as Project Pluto, the idea was to build a supersonic low-altitude cruise missile that could deliver a nuclear weapon to any point on Earth. The tests culminated in 1964, with the ground test of a reactor mounted on a railroad car in Nevada that could run for five minutes, producing 513 megawatts — equivalent to more than 35,000 pounds of thrust.<br>When news of the new Russian cruise missile first emerged, many onlookers assumed it would be a variant of the Project Pluto engine, but Hecla was skeptical. Project Pluto's design, known as a ramjet, required air to move through it very quickly and could only operate at supersonic speeds.<br>"There are a number of reasons we have to suspect that a nuclear ramjet is infeasible for Burevestnik," he said. In particular, the shape of the weapon looks much like a conventional subsonic cruise missile.<br>"You can see very obviously that it is a subsonic system, and ramjets are not very efficient at subsonic speeds," he said.<br>A new kind of reactor
To try and figure out how the weapon was powered, Hecla first used a handful of videos posted by Russian media to determine its dimensions. He identified objects of known size in the factory where the videos were filmed — things like a utility desk or a fire extinguisher. Through many hours of repeated measurements, he was eventually able to build a three-dimensional model of the missile.<br>Based on the measurements, he concluded that Burevestnik is larger than even the largest Russian cruise missiles, but it is by no means enormous. Aerodynamic modeling showed it would need to travel around Mach .75 or about 575 miles per hour to stay airborne. That speed is similar to a commercial aircraft, like the Airbus A320.<br>Hecla now knew roughly how big the reactor could be and how much thrust it needed to produce to make Burevestnik fly. Based on that data, and his knowledge of nuclear engineering, he was then able to model the type of reactor that might be powering the missile.<br>His conclusion: "It's almost certain that the system uses a direct-cycle air-breathing nuclear propulsion system, most likely driving a turbojet," he told NPR.
Related Story: NPR<br>A direct-cycle system means that the reactor runs by pushing air from the atmosphere directly through the nuclear fuel. A compressor forces the air through tiny straw-like channels in the reactor core, where nuclear reactions cause the air to heat and expand out the back of the engine. Such a system is radically different from...