David E. Sanger & William Broad – New York Times December 5, 2011
The huge explosion that destroyed a major missile-testing site near Tehran three weeks ago was a major setback for Iran’s most advanced long-range missile program, according to American and Israeli intelligence officials and missile technology experts.
In interviews, current and former officials said surveillance photos showed that the Iranian base was a central testing center for advanced solid-fuel missiles, an assessment backed by outside experts who have examined satellite photos showing that the base was almost completely leveled in the blast. Such missiles can be launched almost instantly, making them useful to Iran as a potential deterrent against pre-emptive attacks by Israel or the United States, and they are also better suited than older liquid-fuel designs for carrying warheads long distances.
It is still unclear what caused the explosion, with American officials saying they believe it was probably an accident, perhaps because of Iran’s inexperience with a volatile, dangerous technology. Iran declared it an accident, but subsequent discussions of the episode in the Iranian news media have referred to the chief of Iran’s missile program as one of the “martyrs” killed in the huge explosion. Some Iranian officials have talked of sabotage, but it is unclear whether that is based on evidence or surmise after several years in which Iranian nuclear scientists have been assassinated on Tehran’s streets, and a highly sophisticated computer worm has attacked its main uranium production facility.
Both American and Israeli officials, in discussing the explosion in recent days, showed little curiosity about its cause. “Anything that buys us time and delays the day when the Iranians might be able to mount a nuclear weapon on an accurate missile is a small victory,” one Western intelligence official who has been deeply involved in countering the Iranian nuclear program said this weekend. “At this point, we’ll take whatever we can get, however it happens.”
In addition to providing a potential deterrent to attackers, Iran’s advances in solid-fuel missile technology, and the concern it could eventually have intercontinental reach, have been at the heart of the Obama administration’s insistence on the need for new missile-defense programs.
As concerns about Iran’s intentions have deepened in the West, intense surveillance efforts have been turned on suspected Iranian weapons sites. Iran has frequently accused the United States and Israel of spying and sabotage programs, and on Sunday made another such claim, saying it had shot down an advanced American RQ-170 drone in eastern Iran.
That particular drone is among the most sensitive in the American fleet, and if the report is true it would mean Iran had gained at least partial access to closely guarded American technology. A stealth version of the drone was flown for hours, on repeated occasions, over Osama bin Laden’s hide-out in Abbottabad, Pakistan, earlier this year, without being detected by Pakistani air defenses, American officials said. There have been reports for months, all unconfirmed, that the same drone was being used regularly over Iran, presumably to hunt for hidden nuclear or missile sites.
In a statement on Sunday, the American-led International Security Assistance Force in Afghanistan said that the drone “to which the Iranians are referring may be a U.S. unarmed reconnaissance aircraft that had been flying a mission over western Afghanistan late last week.” It added that operators of the remotely controlled drone aircraft lost control of it “and had been working to determine its status.” The statement did not say what kind of drone was lost, or what might have caused the loss.
The statement would seem to suggest that the craft wrongly flew across the border into Iran. If a drone was used for intelligence gathering in Iran, it presumably would not belong to the military — since there are no open hostilities with Iran — but rather to the C.I.A. or another intelligence agency, acting under a presidential finding about the Iranian nuclear program.
One of the many theories swirling around the explosion at the missile base is that it could have been hit by a weapon, including one fired from a drone, setting off the huge explosion that followed. But since no outsiders can approach the base or gather evidence, it is unclear whether it will ever be known publicly what triggered the explosion.
Even if the cause was an accident — and the United States has suffered some with its own solid-fuel motors — several officials said that it was a major setback for Iran’s effort to focus much of its industrial prowess on that kind of missile.
Missiles powered by solid fuels rather than liquids have no need for trucks to fill them with volatile fluids, and can be fired on short notice, making them hard for other nations to destroy before they are launched. That would add to Iran’s ability to protect its nuclear sites from an Israeli strike — a subject of renewed debate in Israel in recent weeks — because Iran could threaten to retaliate before many of its missiles were struck. Solid-fuel missiles are also easier to hide. For those reasons, modern militaries rely on solid fuels for their deadliest missiles.
Moreover, at a time Iran is being squeezed by sanctions, the country has succeeded in making the solid-fuel engines with indigenous technology. For liquid-fueled engines, many key components come from abroad.
In a recent report, the International Institute for Strategic Studies in London called Iran’s shift to solid-fuel engines “a turning point” with “profound strategic implications” because the technology also brings Tehran closer to its goal of making long-range missiles. In its report three weeks ago, the International Atomic Energy Agency laid out, for the first time in public, detailed evidence it says suggests that Iran worked at some point in the past decade on designing a nuclear warhead that would fit atop its missile fleet.
Partly for that reason, Western officials said, many of the sanctions imposed on Iran by the United Nations Security Council seek to block its import of rocket parts.
Last week, the Institute for Science and International Security, a private group in Washington, released a commercial satellite image of the destroyed base.
It called Iran’s labors there integral to “a major milestone in the development of a new missile.”
Government and private analysts described the blast at the military base, which occurred Nov. 12 and killed Gen. Hassan Tehrani Moghaddam, the head of Iran’s missile program, as a major setback — not just because of the extensive damage to the site but also because of the loss of expertise from the specialists working there.
General Moghaddam’s funeral was attended by Iran’s supreme leader, Ayatollah Ali Khamenei. “That was a statement of how central Moghaddam’s work was,” one American intelligence official said.
The sprawling complex where the blast took place has expanded dramatically in the last few years. Michael Elleman, a main author of the International Institute’s 148-page report on Iranian missiles, examined the public images of the destroyed base and said in an interview that the damage and other evidence was consistent with solid-fuel technology.
Mr. Elleman added that the desert area around the base bristled with military compounds and networks of buildings and bunkers — all plainly visible in Google Earth images. Security cordons ringed the bases.
He noted that the region south of the destroyed base, roughly one and five miles distant, held two separate complexes that carried the distinctive signature of a firing range for solid fuels.
The closer of the two sites has eight test stands in a row, and the desert next to them had been clearly scorched by fiery plumes. In such tests, missile engines are mounted horizontally and shoot their blasts straight out.
The more distant complex has three test stands in a row, the middle one bearing bold scorch marks from a recent firing.
David E. Sanger reported from Washington, and William J. Broad from New York.