Monday marks the official launch of an advanced propellants developer that is helping U.S. military aircraft fly faster, farther, longer, higher, and with more payload—all using the same amount of fuel.
Mukund Karanjikar founded sustainable aviation fuel (SAF) provider CleanJoule in 2009. Since then, Karanjikar and a team of engineers have been working behind the scenes with the military and other partners to develop propellants that beat the energy density of existing fuels by up to 32 percent.
That translates to about a 30 percent improvement in range and, for spacecraft, more than double the payload, Karanjikar said.
CleanJoule is now a subsidiary of CycloKinetics, Karanjikar’s new venture targeting aerospace and defense customers.
“They work on different timescales [than civil customers],” he said. “They work on different urgency. They work on different needs based on where they are geographically.”
CleanJoule—which now exclusively serves civil aviation customers—worked with the U.S. Army, Navy, and Air Force for about 15 years to develop fuel that could extend missions and improve performance under high speeds and extreme temperatures. Since mid-2025, all three branches have used CycloKinetics products for “multiple different requirements,” Karanjikar said.
Now, the company seeks to attract more U.S. military and allied customers. It offers three products, each billed as “100 percent drop-in replacements” for existing jet and rocket propellant.
“We took 15 years to absolutely perfect the manufacturing platform,” Karanjikar said. “And now it’s all about scalability, setting up larger reactors with more capital that we intend to raise, both from government as well as private markets.”
Flipping the Script
Karanjikar believes the aviation industry has it all wrong.
For decades, investment has flowed toward new airframes. But over the past 75 years, he said, there has been “zero innovation in how we fly” from a propellant standpoint.
Aircraft flew with gasoline for about 50 years after the Wright brothers’ first flight. The jet era introduced kerosene-based fuels. Jet-A, JP-5, and JPTS came in the 1950s, followed by JP-8 and JP-10 in the ’70s. RP-1 rocket propellant also emerged in the ’50s. Since then, few alternatives have come out.
“The planes look better, the seats are nicer, they are better painted, and it’s much cheaper to fly,” Karanjikar said. “But nothing changed when it comes to propulsion, because it’s a very hard problem to solve.”
From CycloKinetics’ standpoint, propellant should be a “leading variable” and structures a “lagging variable” in aerospace design. In other words, engineers should develop high-performing fuels and tailor airframes to them—not the other way around—so as not to limit themselves in the future.
Had the Lockheed SR71 Blackbird been designed in an era of advanced propellants, it would be “so economical you can’t even imagine,” Karajikar said. In that world, the Blackbird might still be flying rather than in a museum.
“The iPhone, it was never about the songs,” he said. “It was about the operating system that enabled those songs on a small, silicon device. Propellants are exactly that—they enable high-tech use cases.”
Karanjikar said that beyond existing technology, the company’s advanced propellants are designed for “next-generation engines that go beyond just a standard turbine combustion mechanism,” such as Venus Aerospace’s rotating detonation rocket engine.
“That is an uncontested market for CycloKinetics,” he said.
CycloKinetics’ Approach
Karanjikar said CleanJoule and CycloKinetics’ products are “distinct,” but “there are a lot of synergies on the feedstock side, on the facility side, on the types of expertise and talent we need” that make the split sensible.
Though he is not an expert on the manufacturing process, Karanjikar said CycloKinetics’ competitive edge is the production of cyclo-paraffinic hydrocarbons, which “any chemist on the planet would tell you” are “very hard to make.” These molecules contain high-density structures that allow a fuel to be “100 percent drop-in.”
Karanjikar said the company uncovered its production method during testing with the military and other customers.
“That’s the piece we took 15 years to unlock, and with that came a series of benefits,” he said.
Most aircraft use what Karanjikar called “substandard hydrocarbons.” He said CycloKinetics has demonstrated a more than 30 percent improvement in range during testing with an uncrewed aircraft that flies “pretty regularly.” He said “other unmanned systems” not owned by the company have flown “substantially farther.”
Karanjikar also said a “space services company,” which he could not name due to confidentiality, has conducted ground engine testing that indicates its fuels could more than double a rocket’s payload. He added that CycloKinetics is in “advanced conversations” with the company for a real space launch by early 2027. CleanJoule in 2025 notably conducted testing with Venus Aerospace.
The manufacturer offers three products that meet different customer performance requirements.
CycloJP is billed as a replacement for jet-A, JP-5, JP-8, and JPTS. It is designed to improve the range, speed, and endurance for both crewed and uncrewed aircraft, including the military’s collaborative combat aircraft (CCA). That could be particularly useful in large regions such as the Indo-Pacific.
CycloJP is also “freezer-stable,” surviving temperatures as low as minus-70 degrees Celsius to enable high-altitude, long-endurance (HALE) operations.
“You need superior propellants,” Karanjikar said. “Planes and pilots can do only so much.”
CycloRP, formerly produced by CleanJoule as SpaceSAF, is an alternative to kerosene-based RP-1 and RP-2 propellants. Its higher energy density could allow the U.S. Space Force to launch twice as many satellites, while a cleaner combustion process reduces soot emissions to extend the longevity of reusable spacecraft, such as SpaceX’s Falcon 9. That could be particularly relevant as the FAA begins charging for orbital activities.
“People get up in their chairs when they hear double the payload,” Karanjikar said.
The third product, CK-10, is a “tailor-made” replacement for long-range missile systems, extending their range and endurance without requiring larger fuel tanks. Though CycloKinetics bases production in Salt Lake City, it can produce fuels using whatever feedstocks are available, allowing the military to fuel up in-theater.
“It’s about giving more juice but not necessarily more gallons to the systems,” Karanjikar said.
The CycloKinetics chief believes CleanJoule, which has attracted investment from Frontier Airlines, Wizz Air, Volaris Airlines, and other carriers, still has a role to play. But the new company is a “natural progression” that will “pursue things with the speed that the customers require us to.”
