The North-Korean/Iranian Nodong-Shahab missile family

The North-Korean/Iranian Nodong-Shahab missile family
(based on the unknown Soviet missile - here provisionally designated as R-17K)

Norbert Brügge, Germany

Update: 28.12.2021

The riddle of the North-Korean Nodong missile (Hwasong-7) is difficult to decode up to now. It is a missile that presumably uses UDMH/AK-27 as propellant. Pakistan and Iran use the Nodong to build there similar Ghauri-I and Shahab-3 missiles. In North-Korea the Nodong vehicle was used for the first space-rocket Paektusan (Taepo-Dong 1). In the meantime upon base of an extended Nodong have builded North-Korea, Pakistan and Iran their next variants of missiles.
The Nodong missile is an upscaled Soviet R-17 (Scud-B) missile. But, the Scud-B uses in contrast TM-185 (Kerosene) / AK-27I (73%HNO3 +27%N2O4) as propellant.
The key to the problem was up to now the kind of the engine used for the Nodong. Recently were found further remarkable photos from the Iranian Shahab/Safir-engine. The engine is similar to the Scud engine. It is however ~140% larger formed. Also combustor and nozzle are different formed (area ratio 8.2 ---> 9.6). With a meanwhile known diameter the rocket of 1.25 m can be valued a diameter for the nozzle of 62 cm.

Previously it was assumed that it could be an engine of the clustered Chinese engine YF-2. The engine YF-2 is used for the DF-3 missile. The propellant is however UDMH/AK-27S.
The mixing proportion of this components requires approximately equal large tanks. That is also the case at the Nodong missile and Safir IRILV, contrary to the Scud-B !

Meanwhile at first by Novosti Kosmonavtiki published sensational photos of the Chinese first stage engine YF-2 from the DF-3 missile. It is now confirmed that four single engines are combined with its own turbopumps. The shape of the chambers and the nozzles are more similar to the smaller Scud-B engine than to the Nodong engine. The Nodong engine has greater similarity to the Soviet four-chamber engine Isayev S2.1100 (Burya booster). In addition however clear differences between all engines are to be determined. In any case, this engine YF-2 is a creation of Isayev's design bureau. All the details are typical.

It is reported by KB Makeyev that the development of an operational tactical missile (code not known) was stopped in December 1958 in the preliminary planning stage. It should be a R-17 similar missile with a longer range. Was the development later continued ?
An interesting reference for the origin of the Nodong is a drawing for the manufacture of an engine, whose measurements and outlines equal the Nodong engine. It is possible, that this engine belongs to an unknown Soviet missile, which exactly corresponds to the Nodong missile. Possibly the engine was constructed for the use of UDMH as fuel, as for the Isayev engine YF-2. These missile was not taken over however in the rocket arsenal of the Soviets, probably however exports to North Korea. This is realistic because Cyrillic letters were seen on a Shahab-3 (Nodong) missile.

A single Nodong engine has a thrust of approximately 280 kN (s.l.). That can calculated become with the kind of propellant, the quantity of ~11.151 kg and the burning time of 95 sec (Paektusan-1 launch). The Pakistani Ghauri-I missile have a quantity of 12.912 tons propellant. It is calculated a burning time of 110 sec. The Iranian Shahab3 has the same dimension. The new Iranian missile Ghadr-1(H) and the Pakistani Ghauri-II missiles are once more longer (Nodong+).

A stretched Nodong+ were used as first stage of the Safir IRILV and the unknown North-Korean Paektusan-2.

A statement to the Nodong missile by Schmucker Technologie, Munich, Germany , 2010
"The Missile Show". Prof. Dr.-Ing. habil. Robert H. Schmucker & Dr.-Ing. Markus Schiller

�In 1993, four missiles were launched in the DPRK. The exact missile types are still not known for sure, but one is said to have been the first appearance of a new rocket that would soon play a central role in the 3rd World arsenals. This missile, designated Nodong by the West, looks like an upscaled derivative of the Scud. Main diameter is roughly 1.3 m compared to Scud�s 0.88 m, and the whole system is accordingly larger, heavier and offers more per10 formance.
In the same year, a number of Russian missile experts from the Makeev design bureau tried to emigrate to North Korea. This was prohibited by Russian authorities, but it is not known if they found another way to the DPRK.
Since 1998, Nodong can be found in Pakistan by the name of Ghauri, and in Iran as Shahab 3, where it first appeared at a military exhibition, littered with numerous Cyrillic markings.
Lucky chance revealed the true origin of the engine. In 2001, a Russian textbook was published in context with a training course for rocket production in Iran. This book contains the drawing of a manufacturing device for rocket engines. The decisive figures of the according engine � nozzle and throat diameter � perfectly match those of the Nodong engine, as photos of the Iranian Shahab 3 engine clearly show. It is a Soviet-Russian engine, and the characteristic details of the Isaev design bureau are clearly visible.
Engineering details and technical data of Nodong are strikingly characteristic for Soviet missile concepts of the late 1950s. At that time, competing design bureaus proposed, pre-developed and tested dozens of different missiles that never reached the state of serial production and disappeared in the fog of history. To give an example of the scale of Soviet rocket efforts at that time: Isaev alone developed more than a hundred different engines, of which several dozens entered serial production.
Thus, it seems clear that Nodong is an early Soviet missile, perhaps the little known R-18 (better is R-17K; R-18 was other project).�

Quote, 2012, March 15: �The Scud-engine (S5.2) and the Nodong-engine were both designed at Isayev�s OKB-2. The Nodong is not something North Korea developed by "scaling up" the Scud engine. The book: I know both of the authors of this book which contains technical descriptions for the manufacture of the Nodong engine; they both have seen the "Nodong" engine while working in Iran during the late-1990s. They have stated to me that what they saw was an Isayev engine, produced in Russia.�
Source: www.iranmilitaryforum.net/space-technology-and-news/

Overview and Textmarks

	Hwasong-7	Paektusan-1	Shahab-3	Ghadr-F	Ghauri-I	Hwasong-8	Ghauri-II	Ghadr-H	Safir-1	Safir-1B	Safir-1B+	Emad
Length total	~15.9 m	-	~15.5 m	~15.5 m	~15.9 m	~16.6 m	~17.9 m	~16.6 m	-	-	-	~17.1 m
Length without warhead/guidance	~11.5 m	~11.5 m	~11.5 m	~11.5 m	~11.5 m	~13.5 m	~13.5 m	~13.5 m	~17.0 m	~17.0 m	~17.0 m	~13.5 m
Diameter	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m	1.25 m
Propellant	UDMH/AK-27								UDMH/AK-27+	UDMH/N2O4	UDMH/N2O4	UDMH/N2O4
Mass propellant (t)	12.912	11.151*)	12.912	12.912	12.912	14.670	14.670	14.670	~18.200			14.67
Engine	Isayev n.n. (1)
Thrust s.l. (kN)	279.8	279.8	279.8	279.8	279.8	279.8	279.8	279.8	284.4	298.2	333.6	298.2
Thrust vac (kN)	309.2	309.2	309.2	309.2	309.2	309.2	309.2	309.2	313.2	325.8	363.1	325.8
Isp s.l. (Ns/kg)	2383	2383	2383	2383	2383	2383	2383	2383	2422	2540	2658	2540
Isp vac (Ns/kg)	2633	2633	2633	2633	2633	2633	2633	2633	2667	2775	2893	2775
Burn time, nominal (sec)	110	95	110	110	110	125	125	125	155	155	145	125
Total vacuum impulse (MNs)	34.0	29.4	34.0	34.0	34.0	38.6	38.6	38.6	48.6	50.5	53.6	40.7

*) F= (mp * Isp) / t = (11.151 * 2383) / 95 = 279.8 kN

Shahab refueling on-site

Propulsion of the R-17K missile family

Nozzle of Ghauri missile engine (IDEAS 2006)

The Iranian Shahab-3 missile engine

Nodong engine dimensions

Injector plate of Nodong engine

North Korean HS-7 (Nodong) and HS-8 (Nodong+) missile

On Sept. 21, 2017 Vladimir Khrustalev wrote me:
"During my trip to Pyongyang visited Korean People�s Army Museum of Weapons and Equipment. The museum is generally closed for the foreigners with some exceptions. I managed to clarify the DPRK names for various ballistic missiles." The Nodong missile is called as Hwasong-7

Hwasong-7

HS-7 missile (first stage of Paektusan-1)

HS-8

HS-8 missile on unknown homemade TEL

Pakistani Ghauri-I and Ghauri-II missile

Ghauri-I

Ghauri-II

Iranian Shahab-3 & Ghadr-F missile

Shahab-3 missile launch

Shahab-3 with their different guidace units and warheads ------------------->

Shahab-3 with biconic RV (BRV)

Ghadr-F missile

In 2011 there was a missile exhibition in Tehran and for the first time there are exact specifications for several of Iran's missiles such as the Ghadr-F. Then, in 2012 and 2013 was presented this short Shahab-3 like missile with TRV warhead and small Ghadr fins, called Ghadr-F.