Noah Shachtman has a sweet new blog over at Wired called, Danger Room.
Haninah Levine, science fellow at the Center for Defense Information, weighs in on Iran’s so-called “space launch.” With a little help from the Union of Concerned Scientists’ David Wright, Haninah concludes Yawn, It’s a SCUD:
Roughly speaking, if you’re launching something straight up into space, the kinetic energy at the moment of maximum speed (known as burnout speed), just as the engines cut out, is equal to the potential energy at the maximum height of the rocket’s flight. In other words, KEburnout=PEmaximum height.
... if we know the maximum height attained, we can calculate easily the burnout speed. And that’s important, because if we know the burnout speed of the missile used in the test, we can also figure out how far it would have gone if we’d fired it along a trajectory optimized for range, instead of height.
So, what do we get? For a maximum altitude of 150 kilometers, we get a burnout speed of 1.7 km/s – about 3,800 miles per hour. And what do you know – the burnout speed of a SCUD-B, with a 300 kilometer range, just happens to be about 1.4 km/s. Of course, if we wanted to be lazy, we could have followed the “1/2 Rule” – the maximum height a rocket can achieve, fired straight up, is about equal to half its maximum range, fired for distance. Or, we could be even lazier, and note that the good old SCUD-B, with range of 300 kilometers and potential vertical launch height of 150 kilometers, is the favorite example of basic texts on ballistic missiles.
Now, the physics we went through here was a bit slapdash – but if the rocket that was used for this test doesn’t have an exact range of 300 kilometers, it definitely doesn’t have a range of 10,000 kilometers – or even 1,000 kilometers. Simply put, this missile doesn’t go very far. It can’t even reach low-earth orbit, which begins around 200 km. So it’s not even useful for putting satellites into space.
[Also, New Scientist has a helpful story.]
This is a little different, say, than pre-launch speculation by Craig Covault in AvWeek that the missile was “a wolf in sheep’s clothing for testing longer-range missile strike technologies” derived from either the Shahab or the alleged Ghadar-110.
Ghadar 110?
Covault references the “Ghadar 110” as though the existence of the missile were an established fact. In fact, Covault is the first reporter with a respectable publication to imply that “U.S. agencies” (oddly, without the usual adjective “intelligence”) have confirmed it’s existence.
The name “Ghadar” missile—for those of you wondering like I was—entered the public discourse in November 2005 as an accusation by John Bolton’s favorite terrorists, the MEK.
Ghadar—which Covault describes as a solid propellant missile with a 1,800 mile range—sounds suspiciously like the so-called BM-25.
German magazine Bild reported in December 2005 that North Korea sold Iran 18 BM-25 intermediate range ballistic missiles, a story that got more press when Amos Yadlin, head of the Israel Defense Forces Intelligence Branch, repeated it.
I am not ready to start calling the missile the BS-25 as some do … yet ... but I still have big questions about what North Korea did (or did not) sell to Iran. Robert Schmucker, for what its worth, seems to give the story some credence.
I also have some questions about the nature of Russian assistance to North Korea. Paul Kerr and Sonni Efron seem to suggest the former transfered some technology, although how the NORKS used any Russian technology remains a very interesting question. Allen Thomson, Paul Kerr and I have speculated a couple of times (1, 2) in the comments about the North Korea’s missile and the SS-N-6.
No definitive answers, but if Covault really got the IC to confirm the BS … er … BM-25 story … well, that would be news.
Late Update: “A knowledgeable former Department of State official told” Paul Kerr in December “that the reports [of a North Korean IRBM sale to Iran] are ‘certainly credible.’”
Dennis Mosher’s beautiful 1978 painting of prowling Soviet TELs armed with Scud B ballistic missiles is from DIA’s military art collection.
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Some folks have asked about the source of the max altitude. It was Ali Akbar Golrou, deputy head of Iran’s Space Research Center, in Fars.
Here is the text.
— Jeffrey Lewis · Feb 27, 10:23 AM ·
Well, if putative range is 1000km that would still be nearly three times the range of the old Scud B, and as such an improvement. The weight of the scientific payload is unknown, so it’s hard to tell what range a military variant would achieve.
Still, even such a modest improvement would significantly increase Iran’s ability to use their Scud B in a conventional strategic role, say, against targets deep in Iraq or US bases in the region if need arises, and so contribute to Iran’s deterrent/ counterstrike capability.
When speaking of Iran people ought to think beyond Ahmedinejad’s deluded ravings and Israel. It’s not all about nukes.
— confusedponderer · Feb 27, 01:28 PM ·
Yes, except there is no reason to think that the “sounding rocket” has anything like 1,000 km in range.
— Jeffrey Lewis · Feb 27, 02:06 PM ·
I disagree that this was a SCUD missile. First, it would take some engineering to make a SCUD go straight up (the pitch program is hardwired into a SCUD so Iran would need to remove this—and why use a guided missile to go straight up anyway?).
Second, Iran could use its Zelzal-2, a solid propellant rocket that it exports, as a sounding rocket with out the expense of wasting a guidance unit. My estimate for a Zelzal-2, which has a range of 350 km when used as an artillery rocket, is that it could easily reach 200 km altitude.
Finally, a SCUD-B has a payload of 1 ton, far greater than would be needed for an atmospheric experiment. The Zelzal-2 could reach nearly 400 km with a 250 kg scientific payload. A solid propellant Zelzal would be considerably cheaper to use for this purpose.
The most important evidence that this was a SCUD was the picture that appeared in the DangerRoom blog that was clearly a liquid propellant missile. However, it is likely that this was a stock image and not of the actual sounding rocket launch.
— Geoff Forden · Feb 27, 02:13 PM ·
Possible image of Iranian launch (or maybe just a stock pic)
as posted HEREFor comparison, here is a Zelzal-2 with launcher:
— yale · Feb 27, 11:15 PM ·
Who cares? Remember, we can’t wait for the mushroom cloud.
— Mark · Feb 27, 11:18 PM ·
The missile used was not a Scud; that’s all I can tell you. The photo on DangerRoom shows a Shahab-3 (which this launch wasn’t either). This was a simple sounding rocket; a university project. No big deal.
— Ali · Feb 28, 12:44 AM ·
Geoff Forden wrote,
> Iran could use its Zelzal-2, a solid propellant rocket…
This possibility should be considered seriously in light of the reported non-detection of the event by US early warning satellites. A smaller, fast-burning solid rocket would be more likely to go unnoticed (particularly if it happened to be cloudy at the time of launch) than a Scud. Is the total burn time of the Zelzal-2 known?
========
http://www.spacedaily.com/2006/070226193317.gu1nha49.html
US doubts Iranian space launch claim
WASHINGTON, Feb 26 (AFP) Feb 26, 2007
[EXCERPT]
The US military has no evidence to corroborate an Iranian claim that
it fired a rocket into space and suspects that the event never
happened, a US defense official said Monday.
Iranian space officials said Sunday they launched a “sounding rocket”
into space for research purposes, reaching an altitude of 150
kilometers (93 miles). They said the rocket did not go into orbit.
“We have no indication that that’s true,” a US defense official told
AFP, speaking on condition of anonymity. “Nothing we’ve come up with
would indicate that’s happened.”
The official said it was highly unlikely that such a space shot would
have gone undetected by the North American Aerospace Defense Command,
which monitors missile launches worldwide.
“Even our training launches are recorded,” the official said. “There
was nothing on this one.”
“The intelligence assessments points to that the event didn’t happen,”
— Allen Thomson · Feb 28, 09:48 AM ·
Clarification –
Geoff, I did not mean to say that the missile used actually WAS a SCUD – rather, the purpose of my post on Danger Room was to explain how Doug Richardson, speaking to the New Scientist, would have reached the conclusion that “the rocket would have a horizontal range of roughly 300 kilometres… with a heavy warhead – about the same as a Scud missile.”
The title of the piece – “Yawn, It’s a SCUD” – was meant to make a point about the missile’s strategic significance to Danger Room’s general audience, not to make a claim about the missile type to ACW’s more technical audience. On these issues, I certainly defer to your judgment!
— Haninah · Feb 28, 01:03 PM ·
I can only repeat what I said before: Think beyond ‘Iran wants to nuke Israel’ and you still have strategic significance. Don’t yawn too early, folks, you might miss something. The underlying assumption is that the shot was made in context with threatening Israel. Not all strategic weapons are nukes. How ‘chick’ the Iranian nuclear threat atm however is, let’s try avoid myopia.
300km is a decent range in its own right. It test makes still a lot of sense when it is understood as a demonstration of the capability to hit targets like US bases in the region. That is still strategically significant. A vertical shot only makes that point in a very subtle, non-escalative way.
— confusedponderer · Feb 28, 05:41 PM ·
The possible photo (above) of the Iranian launch is not accurate (see the web site of the Australian Space Research Institute -http://www.asri.org.au/SSRP)
— Ali · Feb 28, 06:41 PM ·
Haninah said,
>The title of the piece – “Yawn, It’s a SCUD” – was meant to make a point about the missile’s strategic significance…”
That’s right, I think: Whether this was a Scud, a Zelzal-2, or a new sounding rocket, the bottom line at this point is that the event seems not to indicate any advance in Iran’s military (or other) rocketry capabilities.
— Allen Thomson · Feb 28, 09:00 PM ·
Allen Thomson raises a very interesting and important point: could US launch surveillance satellites have detected the launch of a Zelzal-2 rocket? Of course, the capabilities of America’s DSP satellites are some of the most closely guarded secrets we have. However, we can make some guesses based on what is known and the model I used for the Zelzal—which did, admittedly, use a number of assumptions. The most important assumption, for this discussion, was a 30 second burn time. I arrived at this by scaling up the Iraqi Al Fatah solid propellant missile by volume. You can argue about this scaling process, but it was what I came up with at the time. And I didn’t anticipate this debate which is much more sensitive to burn times than the altitude question, the original question I was interested in.
Given a 30 second burn time, that means that the rocket burns out at 24 km, which is certainly above the rather fuzzy threshold for when DSP starts detecting rocket plumes. However, the rocket was at an altitude of 10 km, perhaps the appropriate lower altitude for detection, only 10 seconds earlier. If true, that means that the rocket would have only been detected once by each of the DSP satellites that were observing it; for perhaps a total of two detections and those at different times in its flight.
DSP satellites are reported to have detected most, if not all, of the Al Husseins launched during the Iraq-Iran war. Those had thrusts of about 24 tons while the Zelzal-2 has a thrust of 32 tons but they also burn for considerably longer and rise to considerably greater heights during thrust than the Zelzal does. Also, and importantly, the exhaust plume intensity of a solid propellant missile is cut by a factor of 2 relative to a liquid propellant missile of the same thrust because of the “dust” in the plume. That means that instead of 32 tons relative to the Al Hussein’s 24 ton thrust, we should compare 16 tons to 24 tons. This and the relatively short time the plume is visible to DSP satellites makes it conceivable that it could have been missed, even give any sensor improvements from the 1980s block DSP to the current blocks.
Ps. In my original post I did not pay sufficient credit to the original DangerRoom post pointing out that this was not a strategic missile. Haninah Levine did a service to the community for tracking that down and pointing it out.
Pps. Jeffrey: we need a way to post missile model files so that people can exchange missile parameter files and use GUI_missile_flyout to simulate the same missiles. I will try to post the Zelzal-2 model on my website, http://mit.edu/stgs/downloads.html but I’m not capable of doing it quickly because of my lack of web-knowledge.
— Geoff Forden · Mar 1, 10:39 AM ·
oops!
I goofed up the conversion from newtons to tons. The thrusts of the two missiles should be
Al Hussein: 11 Tons
Zelzal-2: 15 Tons.
Taking into account the factor of 1/2 for the solid propellant intensity you should compare 7.5 tons to 11 tons.
sorry about the mistake!
— Geoff Forden · Mar 1, 01:08 PM ·