As there is no publicly available imagery of the only Taepodong-2 launch in 2006, all estimates of technical parameters are approximate. Based on the size of the missile, the fuel composition, and the likely fuel capacity, it is estimated that a two-stage variant would have a range of around 4,000 km and a three-stage variant would be capable of reaching as far as 4,500 km, giving it potentially the longest range in the North Korean missile arsenal. The burn time of each stage is a little over 100 seconds, thus allowing the missile to burn for 5 or 6 minutes. Speculative variants of the missile could be capable of a range of approximately 9,000 km. At maximum range, the Taepodong-2 is estimated to have a payload capacity of less than 500 kg. According to a former worker in the publications department of one of North Korea's top research centres, who defected to South Korea, North Korea began development of the missile in 1987. Very few details concerning the technical specifications of the rocket are public information; even the name "Taepodong-2" is a designation applied by agencies outside North Korea to what is presumed to be a successor to the Taepodong-1. The TD-2 first stage likely uses a liquid propellant driven engine and the second stage likely utilises the Rodong short-range missile. Depending on the range, the estimated payload capacity could be as high as 700-1,000 kg at short range, making it potentially suitable for conventional weapons payloads, NBC payloads as well as Earth orbitsatellite delivery. At maximum range, the Taepodong-2 is estimated to have a payload capacity of less than 500 kg. North Korea has yet to demonstrate the ability to produce a re-entry vehicle, without which North Korea cannot deliver a weapon from an ICBM. In 2015, aerospace engineer and North Korea missile program analyst John Schilling stated that North Korea did not seem to be planning to create an operational ICBM from the Taepodong-2 technology, and that the Taepodong-2 had been mistakenly identified as an ICBM development, whereas in reality it was a space launch development vehicle.
Structure
First stage
Taepodong-2's first stage consists of four Rodong motors.
Second and third stages
Little is known about the Taepodong-2 design beyond the first stage. Most likely the second stage is one of the Scud-derived North Korean ballistic missiles, and the third stage most likely uses Chinese solid-fuel engines.
Subsequent launches were intended to launch satellites, using a Taepodong-2 development called the Unha rocket. After two failures in April 2009 and April 2012, its first successful flight, Unha-3, occurred in December 2012 with the launch of the second version of Kwangmyŏngsŏng-3 satellite. This successful flight was repeated on 7 February 2016 with the successful launch of Kwangmyŏngsŏng-4 using a similar rocket as Unha-3 even though the rocket is officially named as Kwangmyŏngsŏng.
