The Hwasong-15 is an intercontinental ballistic missile developed by North Korea. It had its maiden flight on 28 November 2017, around 3 a.m. local time. It is the first ballistic missile developed by North Korea that is theoretically capable of reaching all of the United States mainland.
According to international weapons analysts, the Hwasong-15 first stage has a gimbaled two-chambered main engine system, as opposed to the Hwasong-12 and Hwasong-14 which have one fixed main chamber and four gimbaled steering vernier thruster chambers.
According to missile specialist Norbert Brügge, the missile uses the ‘Paektusan, 백두산’, the first stage of the two stage missile uses an RD-250 clone liquid propulsion system developed by Pyongyang, comprising two combustors fed by common turbopump to increase takeoff thrust. The new propulsion is estimated to have 170 percent increase in thrust, compared to the Hwasong-14.
On November 29, 2017, Michael Elleman wrote for 38 North that at 13,000 km, the payload would be around 150 kg (330 lb), based on flight data of the test and conjectured it was a reconfigured Hwasong-14 and on November 30, after release of the images and video of launch, he wrote a subsequent article on 38th North in which he stated that he first visualized the design of the missile based solely on flight data. After seeing the images and video, Elleman increased the maximum estimate of payload from 150 kg to 1,000 kg (2,200 lb) at a range of 13,000 km. He noted major differences in the design of the actual Hwasong-15 and the missile he visualized the day before, from the dimensions to two nozzles/engine instead of one, such as on the Hwasong-14.
Analysts have noted that the re-entry vehicle has a blunter nose than previous designs, which can accommodate a larger diameter warhead and reduces re-entry stress and heating at the cost of accuracy. Some analysts think it may have been designed with multiple warheads or decoys in mind. More details
