|L. W. (kg)||22,000|
|Thrust (Kg f)||26,000|
|Burn time (sec.)||293|
|Thrust Chamb.||1, 1, 1|
|Third Stage||Solid Motor*|
* May have been derived from existing Chinese designs.
North Korea has successfully developed a missile variously designated the Taep'o-dong-1/Paeutudan-1 (TD-1), No-dong-2, Ro-dong-2, NKSL-1*, Scud Mod-E, and Scud-X. The first designation, which is accepted in the U.S. intelligence community, is used here.
On 31 August 1998, without any advance warning, North Korea launched a space booster—apparently based on the Taepodong I ballistic missile—from a missile test launch pad in eastern North Korea near Taepodong. The launched vehicle was a two-stage ballistic missile, with a solid propellant third stage added. Its No-dong derived booster first stage fell into the Sea of Japan while its Scud-B derived second-stage impacted in the waters off the Sanriku coast. On 4 September, North Korea's Korean Central News Agency reported that the launch had placed an artificial satellite into an elliptical orbit ranging from 219km to 6,978km above the Earth.
No data indicated that such an object as the one claimed by North Korea ever attained a sustained orbit around the Earth. Circumstantial evidence seems to indicate that the satellite achieved orbital velocity before it was destroyed when its solid propellant third stage detonated before burn out. This solid motor may have been derived from existing Chinese Space Solid motors.
The missile configuration was apparently a NKSL-1, a three stage variant of the two-stage Taep'o-dong 1/Paeutudan-1. This attempt revealed considerable detail about the launch vehicle's performance. The TD-1 has two stages (with an estimated range of 2,000-2,200 km) or three stages (with a range of either 2,200-2,672 or 2,200-2,896 km) and a warhead estimated at 700-1,000 kilograms - comparable performance to the Soviet SS-4. The vehicle's first stage consists of a modified No-dong and a second stage based on the North Korean Scud-B missile. If a third stge is present, it consists of a small ellipsoidal solid motor of the type that was used in the August 1998 launch attempt. This launcher appears to be less capable in performance than the French Diamond-A satellite launcher.
In early November 1998 US intelligence informed the Japanese government that North Korea might be preparing to launch another Taepodong missile. An object thought to be a Nodong missile [which could become a Taepodong after assembly], was loaded onto a truck that exited a missile manufacturing plant in a suburb of Pyongyang. The truck was destined for a launch site.
The next flight of the Taep'o-dong-1/NKSL-1 derivative launch vehicle may take place in Iran. From February through April 1999 static test firings of the Taep'o-dong-1/NKSL-1 (redesignated the Shehab-4) booster engines were scheduled to take place in Iran. This would follow a familar pattern. Following the introduction of the No-dong with one flight test by North Korea, it was subsequently flight tested both in Iran as the Shahab-3, and the flight tests of the Ghauri-II of Pakistan. Both are officially recognized by the DoD as No-dong missile system copies. This same testing procedure will probably manifest itself once again in Iran for the Shehab-4. Iran will flight test after the one North Korea test already conducted.
|Taep'o-dong-1 / Shahab-4|
Range to Payload or Throwweight Trade-offs
North Korea may be unwilling to fly their Taep'o-dong-2 booster until after Iran flight tests the Shahab-4. First, it would give North Korea a chance to see if Iran was able to resolve the problems encountered by the Taep'o-dong-1/NKSL-1 during its first flight. Second, North Korea agreed to a moratorium on missile testing in exchange for aid from the United States and other nations. In the meanwhile, modifications to the Taepo'dong-1 launch facility were completed in the fall of 1998 and spring 1999 to make it capable of accomodating flight testing of the Taep'o-dong-2. These modifications are the primary reason why the U.S. intelligence community stated in the spring of 1999 that North Korea was ready to flight-test the Taep'o-dong-2.
In 2003, the Defense Intelligence Agency stated that "We continue to assess that Pyongyang may be ready to test the Taepo Dong 2 (TD-2), perhaps as a space launch vehicle, and perhaps in another country, with little advance warning. A flight test of a shorter range missile also is possible at any time.
"We have no information to suggest Pyongyang intends to deploy the Taepo Dong 1 (TD-1) as a surface-to-surface missile in North Korea. We believe instead that the vehicle was a test bed for multi-stage missile technologies."
|Launch Point|| 40 degrees, 51 min., 17 sec. North|
129 degrees, 39 min., 58 sec. East
|Attempted Orbit||218.82 km x 6,978.2 km|
|Attempted Orbital period||165 min. 5 sec.|
|Approximate inclination||~41 degrees (40.8 degrees?)|
|Height (m)||~26 Satellite launch vehicle, 25 two stages|
|Launch weight total (kg)||20,910-21,870|
|Lift off G's acceleration||1.4-1.5|
|Burn time to orbit||293 sec.|
|Height (m)||~14 m with inter-stage truss structure|
|Launch weight (kg)||15,100|
|Thrust (kg f)||Effective: 30,432|
|Isp. (sec.)||Effective: 226 SL - Due to vanes steering drag loss of 4-5 sec.|
Actual: 230 - SL
|Burn time (sec.)||95|
|Fuel||TM-185 (20% Gasoline + 80% Kerosene)|
|Oxidizer||AK-27I (27% N2O4 + 73% HNO3 + Iodium Inhibitor)|
|Propellant Mass (kg)||12,912|
|Shutdown altitude (km)||35.9|
|Down range distance (km)||19.5|
|Down range impact (km)||253 (180 or more by OH radar)|
|Impact point||40 degrees, 51 min. North, 132 degrees, 40 min. East|
|Payload Shroud Separation||144 sec. in flight, 49 seconds after staging|
|Shroud down range impact||1,100 km or more by radar estimation|
|Height (m)||~10 to third stage interface|
|Launch weight (kg)||~5,260-5,770 kg|
|Launch Thrust Altitude (kg f)||~6,690-7,523 at 50-55% thrust|
|Burn time to staging||<171 seconds operation at 50-55% thrust at altitude to vacuum|
|Fuel||TM-185 (20% Gasoline + 80% Kerosene)|
|Oxidizer||AK-27I (27% N2O4 + 73% HNO3 + Iodium Inhibitor)|
|Shutdown altitude (km)||204 (radar estimates 200-300 km, with one estimate at 400 km)|
|Down range distance (km)||450.5|
|Down range impact (km)||1,646 (radar estimates in excess of 1,550-1,600 km)|
|Impact point||40 degrees, 13 min. North, 149 degrees, 07 min. East|
|Height (m)||~1 or 2 m plus for shroud encapsulation|
|Diameter (m)||~0.65 m|
|Shroud diameter (m)||>0.88 ~ 0.95|
|Launch weight (kg)||~550-1,000 total package - shroud, satellite, and solid motor|
|Launch Thrust Altitude (kg f)||Burn time to staging- 25 sec. observed (27 sec. to orbit after separation from second stage) burn de-orbited the satellite and solid motor or apparently something exploded in the process. Immediately after staging from the second stage the solid motor third stage must utilize a series of small solid motors to spin up the third stage and satellite combination and also properly align itself for the orbit insertion firing while rotating about its center of gravity. There may also have been a small solid motor inside of the base of the satellite. The satellite is said to have been observed in space for 25 seconds after separation from the third stage if that is the correct interpretation of the events but clearly one or any number of these required processes went wrong catastrophically de-orbiting the third stage and satellite. The third stage firing was clearly observed. What actually went wrong is unclear from the available public information. There were parts of a debris field that did fly further down range and reenter.|
|Shutdown altitude (km)||239.3|
|Down range distance (km)||587.9|
|Orbital Injection Velocity (m/sec.)||~8,690-8,980 (7,800 m/sec. observed estimate?)|
|Down range impact||Variously estimated between 2,000-2,200-2,672-2,896 km. These are mathematical modeling estimates for 50-100-700 kg payload or less. As the weapon payload mass within the nose cone air frame becomes smaller the warhead depending on a number of highly technical issues can become quite unstable during reentry above certain velocities. The nose cone airframe mass does exact a fixed payload penalty from the total payload mass available for the weapons payload mass.|
Satellite Kwangmyongsong-1 Payload (estimated data)The satellite's structural design is a sub scale mathematical model version of the Chinese China-1 satellite which is apparently readily available in the public realm.
Developing Nations and Warhead Dynamic Performance
Recently, it was suggested that the developing nations missile program warheads would be tumbling about their center of gravity during re-entry, which would then make it difficult to identify. This was because they were not being spun-up along their longitudinal axis prior to re-entry through the atmosphere.
A warhead is much like a bullet fired from a rifle barrel. If the barrel is grooved to spin up the bullet along its longitudinal axis it tends to fly through the atmosphere to its target more smoothly and accurately. If the barrel is not built with this capability, the bullet tumbles uncontrollably about its center of gravity throughout its flight in the atmosphere to its target. This tumbling reduces the accuracy of the projectile.
This kind of missile warhead tumbling was noted in the ballistic flights of Iraqi's Scud-B, Scud-C/Al-Hussein, Scud-D/Al-Abbas ballistic missiles during the Gulf war. In this particular case all of the warheads remained attached to the Scud derived rocket bodies. The length of the Scud-C and D missile bodies and the failure to spin up either the missile with its warhead or separate the warhead after missile spin up made them extremely unstable and in accurate during re-entry to their target.
Today this is not the case with North Korean derived warhead technology. North Korea successfully demonstrated payload spin up with the satellite launch attempt of the Taep'o-dong-1 or PAEUTUSAN-1 booster. The Paeutusan-1 solid propellant third stage both demonstrated a near full duration burn and the spin up of the stage and satellite along its longitudinal axis. However, the third stage solid motor ruptured, de-orbiting the satellite, almost immediately after orbital insertion while achieving orbital velocity.
Therefore, it would be correct to assume that besides North Korea's, No-dong (first stage of Taep'o-dong-1), both Pakistan's Ghauri-II and Iran's Shahab-3 all benefit from this spin-up technology. The Shahab-3/Ghauri-II both apparently spin up the single booster stage and warhead combination starting at about 10 seconds before the termination of the powered flight at 110 seconds. At this point after 110 seconds of powered flight the warhead is then separated from the booster stage to fly on a re-entry trajectory that remains stable to its target. With the addition of GPS targeting the warhead accuracy is greatly enhanced. There are still many in the analytical community that question, perhaps correctly, this suggested accuracy of 190 meters to over one kilometer. There can be no doubt that this spin-up technology does improve the accuracy of these warheads over the previously demonstrated poor capability. Since the warheads are not tumbling it in fact enhances the interceptor sensor signature identification capability verses that of a tumbling warheads signature.
Equally revealing is the fact that this is the area where the Iranian Shahab-3 has repeatedly failed in flight test. If the steering vanes are not equally positioned correctly or are defective in any way the missile and warhead combination would tumble about its center of gravity out of control destroying the missile. The resulting tumbling warhead whether attached to the remaining missile body or not would in all probability be destroyed during its re-entry. It is known that Iran has and continues to suffer from a steering vane quality control problem for its Shahab-3 ballistic missile that the Germans during WW-II solved and that the United States and former Soviet Union were able to easily resolve with out using specialized coating.