Tag Archives: N. Ramani
Analysis of North Korea’s February 2016 Successful Space Launch
Authors: S. Chandrashekar, N. Ramani, Arun Vishwanathan
To read the complete report click here
To cite: S. Chandrashekar, N. Ramani, Arun Vishwanathan. Analysis of North Korea’s February 2016 Successful Space Launch. ISSSP Report No. 02-2016. Bangalore: International Strategic and Security Studies Programme, National Institute of Advanced Studies, April 2016, available at http://isssp.in/analysis-of-north-koreas-february-2016-successful-space-launch/
The Democratic Peoples’ Republic of Korea (DPRK) or North Korea succeeded in placing a 100 kg Earth Observation (EO) satellite Kwangmyongsong-4 into a Sun Synchronous Orbit (SSO) on February 7, 2016. As it had done in earlier launches, the DPRK used its Unha-3 launch vehicle for the latest mission. The launch was conducted from the Sohae Space Center in Ch’o’lsan County, North Pyongyang Province.
North Korea has so far conducted six space launches. The last two launches conducted in December 2012 and the recent February 2016 launch have been successful in placing small remote sensing satellites into “more difficult to reach” sun synchronous orbits.
Based on available information put out by various agencies including official North Korean sources this report attempts to reconstruct the trajectory of the February 2016 launch. Using this reconstruction of the trajectory it goes on to make inferences about the technical parameters of the launcher. It builds upon and complements an earlier study carried out by the ISSSP on North Korea’s successful launch of 2012 to provide an update on North Korea’s launch and space capabilities.
On February 2, 2016, the North Koreans had released information about an impending space launch to the International Maritime Organisation (IMO). The statement indicated a launch window stretching from February 8 to February 25, 2016. It also provided the area coordinates or impact zones for the spent stages and the shroud. On February 6, 2016, the DPRK narrowed down the launch window to February 7-14. The launch took place on February 7, 2016, the first day of the revised launch window.
Analysis of the Unha-3 Launch using NIAS Quo Vadis Trajectory Software
The analysis was carried out using the Quo Vadis trajectory software developed at the National Institute of Advanced Studies (NIAS), Bangalore. Using an iterative trial and error process involving changes in the various launch vehicle parameters very similar to those used in our analysis of the 2012 launch we attempted to arrive at a trajectory in which the impact points of the first stage, second stage and shroud are closely matched with the nominal impact points put out by North Korea. Along with this we also introduced needed maneuvers to the first, second and third stages for realizing an orbit that matched well with the NORAD orbital data.
With two successful satellite launches, North Korea has indicated its capability to indigenously design, develop, test and integrate advanced technologies like a new engine for its launch vehicle. More importantly, the two launches have highlighted the North Korean capability to bring together the hard technologies with the softer parts of the launch like mission planning and management.
For placing the satellite into a sun synchronous orbit, North Korea has to carry out maneuvers after liftoff, pitch down the second stage after the first stage separation and also carry out a yaw maneuver of the third stage before injection of the satellite into orbit.
Successful mastery of these difficult technologies and a complex mission indicates the progress in rocket and missile technology that the North Koreans have achieved since their first failed launch in April 2012. The launch trajectory and the initial orbits of the February 2016 launch of the Unha-3 as computed by the Quo Vadis software is depicted in Figure below.
Click here to download the KMZ file for the Unha-3 Trajectory
Unha-3 as a long-range Ballistic Missile
North Korea conducted four nuclear tests with the latest test in January 2016. In addition it has successfully put a satellite into orbit twice – in December 2012 and February 2016. With these capabilities, North Korea is moving towards the capability to miniaturize its nuclear warhead and delivering them on long range missiles.
Though the Unha-3 is primarily designed for a space mission, it can be modified into a long range ballistic missile. Trajectory analysis using the NIAS trajectory modelling software – Quo Vadis – shows that a due North East launch (25o azimuth) of the Unha from a suitable location with a 1000kg payload (sufficient to carry a nuclear warhead) can reach all of Alaska and some parts of northern Canada. As indicated in an earlier ISSSP, NIAS report, if North Korea manages to reduce the payload mass to 800kg it will be able to successfully deliver a nuclear warhead on parts of western coast of the continental United States including the states of Washington, Oregon and northern parts of California.
Figure below provides a visual representation of the range of the Unha 3 launcher if it is deployed as a long range missile.
About the Authors
S. Chandrashekar is JRD Tata Chair Professor in the International Strategic and Security Studies Programme, NIAS, Bangalore. He can be reached at chandrashekar.schandra[at]gmail.com
N. Ramani is Visiting Professor in the International Strategic and Security Studies Programme, NIAS, Bangalore. He can be reached at narayan.ramani[at]gmail.com
Arun Vishwanathan is Assistant Professor in the International Strategic and Security Studies Programme, NIAS, Bangalore. He can be reached at arun_summerhll[at]yahoo.com
Launch of Pakistani Shaheen-II (Hatf-VI) Ballistic Missile on November 13, 2014: An Analysis
Authors: Rajaram Nagappa, S. Chandrashekar, N. Ramani, Lalitha Sundaresan and Viswesh Rammohan
To read the complete report in PDF click here
A launch of the Shaheen II (Hatf-VI) ballistic missile was carried out by the Pakistan Army Strategic Forces Command on 13 November 2014. What is significant about this launch is that it is taking place after a gap of nearly six and half years. The last announced Shaheen-II launch had taken place on 19 and 21 April 2008. The range claimed in those flights was higher at 2000 km.
A related issue is that the launch was conducted over the Arabian Sea and the Notice to Mariners/Airmen issued in advance identified missile launch window and the coordinates of the impact zones. With the available information from open sources an analysis is carried out of this flight and where relevant comparison is carried out with the launch of April 2008.
Based on available information, it would appear that the Shaheen-II launched on 13 November 2014 performed a successful flight. The Shaheen-II flight occurred after a gap of 6.5 years. The range of 1500 km indicated in the press release fits with the announced impact zones. The following questions come to mind:
- It is quite likely that the design range of the missile is only 1500 km. NAVAREA warnings for the 2008 flights are non-existent and therefore of it can be surmised that these flights were carried overland from Tilla Range. The 2000 km range claimed for these flights could therefore be overstated.
- If this is so, our estimate of the propellant and inert mass of the stage motors should also be wrong. If the propulsion parameters are overestimated by us, it would mean either a) the diameter of 1.4 m of the missile is in error or b) the design is not very efficiently carried out.
- Alternately, the propulsion parameters derived are nearly correct and the actual range of the missile is approximately 2133 km. A lofted trajectory was attempted in the November 2014 flight to get a lower range.
- Accepted practice is to qualify a missile system for its nominal performance. What is the reason therefore for trying a lofted trajectory, in a developmental mission, especially as there is no range constraint?
- The long interval in the resumption of the Shaheen-II flight is indicative of a major technical issue, which may have taken time to resolve.
- The possibility of technical problem is corroborated by a recent report emanating from Hong Kong.
- Shaheen-II, unlike the other missiles in the Pakistani arsenal is a two-stage system. Design and performance issues could arise in respect of : (a) sequencing of staging events, (b) transfer of control at the end of first stage burn, (c) vehicle bending modes and structural design, (d) management of vehicle vibration – e.g. issues relating to control system/structure interaction, (e) thermal management of reentry heating to name a few. If the April 2008 flights had brought out any such inadequacies, the planning of the corrective action required, its realization and implementation could explain the long timespan in the resumption of the missile flight. It is possible that remedial action has not reflected in changes to the overall configuration and dimension and therefore is not discernible in the images of the flight vehicle.
- The changes may however, have impact on the inert mass of the vehicle and the throw weight, thus impacting the performance.
- Procedural issues, lack of priority or financial/resource constraints could also be causative factor for the delay.
In short, the long time gap can only be explained assuming that the Shaheen-II flight of April 2008 exhibited some major anomaly in one or more of the subsystems (e.g. issues relating to staging, control, vehicle flexibility and coupling effects, reentry thermo-structural) and it has taken Pakistan a long time to diagnose, correct (perhaps with Chinese help) and qualify the corrective measures. The corrective measures in turn may have impacted on the inert mass and consequently on the performance. Additionally, if the PSAC has also been incorporated, the development and qualification of such a system would have taken up time, besides adding mass to the missile throw weight.
The Shaheen – II flight. Of 13 November 2014 is analysed. A launch location west of Somniani range is identified and corroborated with assessment of the historical images. The flight over open areas of the Arabian Sea seems to be a logical outcome after the failure of Ghauri flight launched over land in November 2012. The range of the missile has been simulated and matched with the impact location given in the NAVAREA IX warnings. Though a lofted trajectory simulation shows good match with the known impact locations, reasons for justifying such a trajectory is elusive. Reasons for the long gap are difficult to explain in the absence of confirmatory data and can only be speculated to be a combination involving technology issues, correction, requalification and use of PSAC as well as availability of resources and priorities.
The Hindu, March 5, 2014
China’s Anti-Ship Ballistic Missile: Game Changer in the Pacific Ocean
S. Chandrashekar, R.N. Ganesh, C.R. Raghunath, Rajaram Nagappa, N. Ramani and Lalitha Sundaresan
An ISSSP Report titled ‘China’s Anti-Ship Ballistic Missile: Game Changer in the Pacific Ocean’ was quoted by The Hindu to highlight the Chinese system of using land-based ballistic missiles to deter America’s powerful nuclear-powered aircraft carriers from coming anywhere near its coast. The link of the entire story which appeared on March 5, 2014 is given below.
For the entire link click here
The study was undertaken by a group at the ISSSP, NIAS to make an analytical assessment of China’s capability to design and develop an Anti-Ship Ballistic Missile directed against an Aircraft Carrier Strike Group (CSG), and also the Chinese ability to create the technical infrastructure required to transform this missile into an operational weapon system.
To read the complete report click here
North Korea’s Successful Space Launch
Authors: S.Chandrashekar, N.Ramani, Rajaram Nagappa and Soma Perumal
To read the complete report in pdf click here
Using publicly available information and images of the Unha launcher as well as the specific information on the first stage put out by South Korea after recovering and analyzing the debris from the first stage, the International Strategic & Security Studies Programme (ISSSP) at the National Institute of Advanced Studies (NIAS) attempted to reconstruct the trajectory of the successful launch.
For the December 12 2012 launch of the Unha, a lot of information was publicly available or reasonable estimates could be made from images of the launcher. This enabled us to reconstruct the trajectory flown by the Unha launcher with a reasonable degree of accuracy. Through an iterative process we were able to obtain a trajectory that matches well with the midpoints of the notified impact zones as well as the achieved orbit.
The analysis suggests that North Korea is somewhat more advanced than either Iran or Pakistan in space and missile technologies and products. This assessment, more than the actual performance of the Unha launcher as a missile, must be a source of considerable concern to North Korea’s immediate neighbours as well as the United States.
The available evidence based on the recovery of the first stage debris by South Korea indicates that the first stage of the Unha Launcher comprises a cluster of four Nodong Engines that have a common turbo pump and common tanks for the kerosene propellant and the RFNA oxidizer. The first stage sea level specific impulse that best fits the trajectory is only 229 seconds as compared to the initial assumed value of 232 seconds. This is consistent with a Kerosene RFNA fuel and oxidizer combination typical of the original Scud A Soviet era technology that has been modified and scaled up for a space booster application.
The second stage of the Unha does not use a Nodong engine as assumed by most analysts. We found that the second stage vacuum specific impulse that best fits the trajectory is about 270 seconds. This is not compatible with the 250 to 255 seconds vacuum specific impulse of the Nodong that uses a kerosene RFNA fuel oxidizer combination. The second stage most probably uses a UDMH RFNA fuel and oxidizer combination that is compatible with the Scud B technology of the Soviet era. Though it would have been easier for the North Korea to have used a regular missile engine for the Unha second stage they choose to develop an engine and stage specifically designed for a satellite mission. This indicates a substantial in-house capability that has built upon imported technology to not only improve it but to use the knowledge acquired to scaleup, re-design, develop, test and launch a new stage.
The ISSSP’s in-house Trajectory Model also suggests that the third stage uses an advanced engine with a specific impulse in the range of 288 to 290 seconds. The results also suggest that this is a light weight stage with a high propellant load factor of around 86%. The engine that powers this stage uses an advanced propellant oxidizer combination such as UDMH and Nitrogen Tetroxide.
This propellant and oxidizer combination was not used in the Scud series development. North Korea’s possession of this stage indicates that they have the knowledge and capabilities to indigenously design, develop, test and integrate such an advanced engine and stage into a space launcher. This is no mean achievement for a supposedly backward country like North Korea.
Though the Unha has been primarily designed for a space application it can also be used as a missile. The range of the Unha with a 1000 kg payload launched due north towards the US or Canada is 5950 Km. A due North East launch from the Launch site with a 1000 kg payload (sufficient for a nuclear warhead) can reach most parts of Alaska.
Apart from these hard technological achievements related to the development of the propulsion units and the stages for the Unha, the launch provides visible evidence that North Korea has been able to integrate these hard technologies with the softer technologies of mission planning and management of a complex project. The vehicle trajectory including the maneuvers after liftoff, the pitching down of the second stage after first stage separation, maintaining control during the fairly long coast phase, the yaw maneuver of the third stage and the final injection into a fairly good sun synchronous orbit shows a strong and well developed internal organization of effort within North Korea. The division of work and the integration of these various diverse subsystems and components into a whole launcher and the planning and execution of the launch mission show that North Korea has made commendable progress in its mastery of missile and space launcher products and technologies.