North Korea’s Missile Success Is Linked to Ukrainian Plant, Investigators Say

North Korea’s success in testing an intercontinental ballistic missile that appears able to reach the United States was made possible by black-market purchases of powerful rocket engines probably from a Ukrainian factory with historical ties to Russia’s missile program ..

.. After those failures, the North changed designs and suppliers in the past two years

.. Government investigators and experts have focused their inquiries on a missile factory in Dnipro, Ukraine, on the edge of the territory where Russia is fighting a low-level war to break off part of Ukraine.

.. During the Cold War, the factory made the deadliest missiles in the Soviet arsenal, including the giant SS-18. It remained one of Russia’s primary producers of missiles even after Ukraine gained independence.

.. the state-owned factory, known as Yuzhmash, has fallen on hard times.

.. The new missiles are based on a technology so complex that it would have been impossible for the North Koreans to have switched gears so quickly themselves. They apparently fired up the new engine for the first time in September — meaning that it took only 10 months to go from that basic milestone to firing an ICBM, a short time unless they were able to buy designs, hardware and expertise on the black market.

.. “I feel for those guys,” said Mr. Elleman, who visited the factory repeatedly a decade ago while working on federal projects to curb weapon threats. “They don’t want to do bad things.”

.. But the R-27 was complicated, and the design was difficult for the North to copy and fly successfully.

.. the Yuzhmash plant in Ukraine, as well as its design bureau, Yuzhnoye. The team’s engines were potentially easier to copy because they were designed not for cramped submarines but roomier land-based missiles. That simplified the engineering.

.. Moscow withdrew plans to have Yuzhmash make new versions of the SS-18 missile.

.. the Ukrainian factory remains financially beleaguered. It now makes trolley buses and tractors, while seeking new rocket contracts to help regain some of its past glory.