An Analysis of the Pakistani Ghauri Missile Test (6 April 1998)
April 23, 1998
David Wright
Union of Concerned Scientists and
Security Studies Program, MIT
The following analysis is based on information that has been reported about the
Pakistani Ghauri missile test of 6 April 1998 combined with an understanding of
the North Korean Nodong missile.
Description of the Ghauri Missile
Press reports about the Ghauri flight test typically mention a maximum range of
1,500 kilometers for the missile, but the range of the test is usually given as
1,100 km with a flight time of 9 minutes and 58 seconds.[1] Many reports mention
that the missile rose to an altitude of 350 km. This appears to refer to the
apogee, or highest point of the trajectory, which occurs in the middle of the
trajectory.
Several reports have given the total mass of the Ghauri missile as 16 tonnes and
the payload as 700 kg; fuel masses of both 13 and 14 tonnes have been
reported.[2] However, a fuel mass of 14 tonnes would give a fuel fraction for
the booster of 91.5%, which appears unrealistically high without access to very
lightweight materials. On the other hand, a fuel mass of 13 tonnes would give a
fuel fraction of 85%, which is a reasonable value assuming the missile body is
made of aluminum, rather than steel (which Scuds are made of). Thus we assume
the missile has a total mass of 16 tonnes and a fuel mass of 13 tonnes.
If these figures for the Ghauri are correct, the missile appears to be somewhat
smaller than the North Korean Nodong missile. The Nodong mass is estimated to be
a couple of tonnes larger than these values (about 15 tonnes of fuel and 18.5
tonnes total mass if the body is made of aluminum).[3] This is consistent with
reports that the Ghauri was not a Nodong, although the design and technology are
probably similar to the Nodong.
Similarly, from the photos of the Ghauri launch that were released by Pakistani
television, one can get a very rough estimate of the size of the missile based
on the trucks in the background.[4] From this, the missile appears to be very
roughly the same size as, though possibly smaller than, the Nodong, which is
reported to be 15.2 meters long and 1.2 meters in diameter.
The missile can reportedly be fired from a mobile launcher[5] and is believed to
be single stage. At least one report stated that the Ghauri is three-stage, but
this appears to be a misinterpretation of Pakistani reports that "the missile
will formally be tested in three stages..."[6]
To better understand what might be behind the press reports of the Ghauri test,
I have calculated what one would expect from a missile based on Nodong
technology with the masses described in the press reports. I have found that
this appears to be consistent with a missile capable of flying 1,100 kilometers
with a 700 kg payload. However, I have also found that some of the numbers are
consistent with a missile having a range of 800 kilometers, which is roughly
what Pakistan has been claiming for the Hatf 3 it is developing. Thus it appears
possible that Pakistan may have tested a shorter-range missile and exaggerated
its range.
A Test to a Range of 1,100 Kilometers?
Press reports have given the launch site of the test either as Malute, near the
city of Jelum,[7] or as near the Kahuta nuclear research lab.[8] Several reports
of impact locations have appeared. One of these said it occurred in Mekran,
which would be consistent with a test of 1,100 kilometers from either of the
launch sites.[9] A colleague in Pakistan told me that he had heard that the
missile landed in south coast of Baluchistan, which would also be consistent
with this range.
My calculations show that a missile powered by four Scud engines (which is the
Nodong configuration) and having a total mass of 16 tonnes with 13 tonnes of
fuel would have a maximum range of about 1,100 km with a 700 kg payload. (This
assumes a sea-level specific impulse of 222 seconds, which is the value for Scud
B engines fueled by kerosene and nitric acid.) The standard trajectory for this
range would give an apogee of about 300 km and a flight time of about 9.6
minutes. However, if this missile was flown on a slightly lofted trajectory, it
could still reach 1,100 km range but with an apogee of 350 km and a flight time
of just over 10 minutes, which would agree with the press reports. Thus, the
press reports might be consistent with a missile somewhat smaller than a Nodong,
but using the same technology and configuration.
It is interesting to note that if the payload of such a missile were reduced
from 700 kg to 200 kg, the range would increase to roughly 1,500 kilometers,
which is the reported to be the maximum range. A payload of 200 kg might be
roughly the smallest possible since it could represent the structural mass of
the nose section without a warhead.
A missile of the type described here would have a range of 950 kilometers with a
one-tonne payload and a range of about 800 kilometers with a 1.5 tonne payload.
By comparison, a Nodong missile with a similar fuel fraction (85%) would have a
longer range-roughly 1150 kilometers for a one-tonne payload.
A Test to a Range of 700 Kilometers?
It is possible, however, that the range of the test was considerably shorter
than 1,100 kilometers. A number of press reports state that impact occurred near
the city of Quetta.[10] Another report stated that the impact occurred in the
northern part of Balochistan.[11] From a map it is easy to verify that such a
flight would have a range of only about 700 kilometers.
If the flight test was 700 km rather than 1,100 km, this raises the possibility
of a different explanation. In mid-1997, Pakistan claimed to be developing an
800 kilometer-range Hatf 3 missile. An 800 kilometer-range missile on a standard
trajectory would have an apogee of about 200 kilometers and a flight time of 8
minutes. However, if the missile trajectory was lofted slightly to give an
apogee of 350 km, the figure reported in the press, my calculations show that
the missile would then have a range of about 700 km and a flight time of ten
minutes. Thus the figures for the apogee and flight time given in the press are
consistent with a shorter flight range that agrees with the distance between the
launch and impact locations given in some reports. This possibility cannot
therefore not be ruled out on these grounds.
It is interesting to note that if the payload on this missile were reduced from
700 kg to 200 kg, the range would increase to about 1,100 km.
What Does This Mean?
Some Indian sources appear skeptical of the claims about the Ghauri test. Such
attitudes could well have political motivations. One report, however, states
that Indian radar did not detect a test despite the fact India constantly
monitors Pakistan and questions whether Pakistan would launch an unproven
missile over populated areas without issuing an alert.[12] Some observers
suggest that if a test did occur, this last point indicates the missile must
have been a proven design from China (North Korea does not have a proven missile
of this range).
US intelligence appears to believe that a test did occur, although it is not
known what range it believes the test may have covered.
While there continue to be reports suggesting Chinese assistance for the Ghauri,
US officials are reported to believe that the Ghauri missile is liquid-fueled
and is based on technology obtained from North Korea.[13] North Korea is
believed to have transferred "major components" according to one source, but the
United States believes that Pakistan did not receive a whole Nodong missile from
North Korea. These transfers are said to have taken place over the past two or
three years.
There have been contacts between Pakistan and North Korea in the past, some of
which are reported to have involved missiles. For example, there are reports of
Pakistani officials visiting North Korea in 1992 to discuss the Nodong program
and Pakistani officials are said to have been present in North Korea for the
1993 flight test of a Nodong. In December of 1993, Pakistani Prime Minister
Benazir Bhutto spent two days in Pyongyang. These contacts are reported to have
led to cooperation on developing the Ghuari missile.[14]
It is worth noting that Pakistan's earlier experience with missile design (the
Hatf 1 and 2 missiles) was with solid-fuel engines, so that if the Ghauri is
liquid-fueled it would suggest some level of assistance from abroad.
The information given in press reports about the missile and the flight test are
compatible with the missile being liquid fueled and using a cluster of four Scud
engines, as does North Korea's Nodong missile. However, the missile appears to
be somewhat smaller and have a shorter range (with comparable payload) than the
Nodong. This supports assertions that North Korea did not transfer a complete
missile, and may support Pakistani claims that it was an indigenous design,
albeit one that drew heavily on foreign technology and expertise.
For simple liquid-fueled engines of this type, clustering is an obvious step to
increase missile range and should not be a difficult thing to do. If Pakistan
has working short-range, Scud-type liquid-fueled engines that it has either
developed or purchased, it seems plausible that it could build a
1,000-kilometer-range missile by clustering engines. Ground tests of a missile
engine were reported in Pakistan last year, which may have been an engine it
used in the Ghauri.
An alternate possibility that cannot be ruled out with available information is
that Pakistan has a missile with an 800 kilometer range and that the April 6
test was only 700 kilometers. This would be consistent with a number of reports
of the launch and impact sites and with Pakistani claims last year that it had
developed an 800 kilometer-range Hatf 3, although apparently no test of a
missile to that range has been observed. As mentioned above, ground tests of an
engine being developed were reported last year, and were believed to be for Hatf
3 missile.
References:
1 "Pakistan test-fires 1,500-km range missile," The News (internet edition), 7
April 1998; Hasan Akhtar, "Pakistan test-fires Ghauri missile," Dawn, 7 April
1998 (this reference gives the flight time as 8 minutes, but this appears to be
incorrect since the time given for the launch is two minutes later than the time
shown on the video of the launch).
2 Akhtar, "Pakistan test-fires Ghauri missile"; "Pakistan test-fires 1,500-km
range missile," The News; "Pak test-fires surface-to-surface missile," Rediff on
the Net, 6 April 1998.
3 David Wright and Timur Kadyshev, "An Analysis of the North Korean Nodong
Missile," Science and Global Security, Vol. 4, 1994, p. 129.
4 The photo can be seen at
www.jang-group.com/thenews/apr98-daily/07-04-98/frmain.htm.
5 "Pakistan test-fires 1,500-km range missile," The News.
6 Amit Baruah, "Pak. tests 1,500 km range missile," The Hindu, 11 February 1998,
p. 13.
7 Akhtar, "Pakistan test fires Ghauri missile"; Shameem Akhtar, "Missile race
in South Asia," Dawn, 21 April 1998.
8 Zahid Hussain, "Pakistan missile test stirs tension," South China Morning Post
(internet edition), 7 April 1998, Kathy Gannon, "Pakistan test fires missile,
irking India," Washington Times, 7 April 1998, A13.
9 Akhtar, "Missile race in South Asia."
10 Hussain, "Pakistan missile test stirs tension"; Akhtar, "Pakistan test-fires
Ghauri missile"; and "Pak test-fires surface-to-surface missile," Rediff on the
Net.
11 "Pakistan: Foreign Office Spokesman on Ghauri Test," The Nation (internet
version) in FBIS-TAC-98-097, 7 April 1998.
12 "Indians disparage Pakistan missile claim," Washington Times, 11 April 1998,
A7.
13 Time Weiner, "U.S. Says North Korea Helped Develop New Pakistani Missile,"
New York Times, 11 April 1998, p. A3.
14 For a more extensive discussion of North Korean-Pakistani missile
cooperation, see Joseph Bermudez Jr., "DPRK-Pakistan Ghauri Missile
Cooperation," to be published.
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