She flew on liquid oxygen and oil: the DPRK stated that her rocket had exploded through new fuel

"Initial analysis showed that the cause of the malfunction is related to the recently developed liquid-fuel missile engine, but now they are investigating other possible reasons," Pyongyanana said in the state media. Although the state media did not name the type of rocket and did not publish photos, analysts said it is most likely different from the Callim-1 missile, which was used in the successful launch of the satellite in November 2023.

US officials and independent analysts have stated that Callima-1, apparently, is based on systems designed for North Korean intercontinental ballistic missiles with nuclear warheads that usually do not use liquid oxygen due to low temperatures required for storage.

The engine on oil fuel and liquid oxygen may indicate that Russia, which has promised to help the satellite program of North Korea last year, could provide assistance, said Lee Chun Iin, an honorary researcher at the South Korean Institute of Scientific and Technical Policy. "Even if Pyongyang fails, it is a huge jump," he said, noting that some of the South Korean space missiles were originally developed together with Russia a few decades ago and used similar technology.

"Russia is the strongest country in the field of liquid oxygen-gassing fuel, and our Nai and Nuri missiles use it through technical cooperation with Russia," Lee said. Liquid oxygen boils at -183 ° C and requires special storage and equipment. This may explain why North Korea conducted several static rocket tests at the end of last year, he added.

"It is very difficult to solve the problems of unstable combustion in this fuel system and apply materials and parts that can withstand extremely low temperatures," Lee said. Russian experts have visited North Korea to assist in the implementation of the satellite and rocket program, reports Yonhap with reference to the unnamed high-ranking representative of the Ministry of Defense of South Korea.