In annual war games that started in the Persian Gulf last week, the Iranians say they have tested an underwater sonar-evading missile capable of going 375 kilometers per hour -- three or four times faster than conventional torpedoes.
They also claim to have test-fired a multiple-warhead missile that can almost entirely evade radar.
Military Analysts Skeptical
Military analysts say they don't have enough hard information to form a definitive view of the latest Iranian claims, and say they cannot be rejected out of hand.
But London-based independent military consultant Alexandra Ashbourne says she would be "really surprised" if the Iranian claims are true. She singles out the rocket with alleged radar-avoiding qualities, called the Fajr-3.
"That's the kind of thing we [in the West] are having trouble with, and whether they have this incredible.... I mean we know they have some capabilities, but whether their capabilities are really as advanced as they would like us to believe is another matter," she says.
Ashbourne says the ability of a rocket to avoid appearing on radar screens depends largely on the materials it's made of. Modern carbon fiber or Kevlar materials are like hard and heat-resistant plastic, and reflect far fewer radar waves than metal does. Hence they leave a smaller radar "footprint."
The science of trying to make missiles, airplanes, and even boats "invisible" to radar is called stealth technology. But Ashbourne says only partial invisibility of missiles has been achieved, as far as is known.
"You can achieve stealth up to a point comparatively easily in this day and age, but according to the [Iranian] claims I have heard, they appear to be at Western or above-Western capability, and I would be really surprised [if this is true]," she says.
Overstating The Technology?
Turning to the underwater missile, called Hoot (Whale), Iran's Islamic Revolution Guards Corps General Ali Fadavi told state television that no vessel can escape from this missile because of its speed.
Fadavi said only Russia possesses an underwater rocket with such speed. He was referring to the Shkval, which covers 100 meters per second and has a range of 6.9 kilometers. It's not known if the Hoot is based on the Shkval, or whether it is nuclear-capable.
Naval security analyst Jason Alderwick, of the International Institute for Security Studies in London, has studied video footage of the underwater missile released by the Iranian government, and is skeptical.
"Certainly they seem to have undertaken some form of test, of some 'missilized' underwater projectile, but to go so far as to claim it is a credible, fully operational underwater missile I think is overstating [the matter] considerably," he says.
Alderwick points out that the best conventional torpedoes have a speed of about 110 kilometers an hour, and that to get them to run at three or four times that speed through rocket power is no easy matter.
"There are significant problems in maneuvering the missile, the noise it would make is obvious as well, it is not very stealthy, there are really a plethora of issues that create problems when you are trying to develop high-speed underwater torpedoes," he says.
Another "massive problem," Alderwick continues, is range. Pushing a rocket at high speed through a dense substance like water means a high consumption of fuel. Russia's Shkval has a range of nearly 7 kilometers. There is no word on the Hoot's range, but assuming it is similar to the Shkval, this means such a rocket is only useful when opposing ships are at close quarters.
Alderwick points out two other weak points. One, that the launching vessels are very vulnerable to air attack, for instance by helicopter gunships.
Second, if the missile is to be used against submarines, as Iranian officials suggest, then it needs to be supported by a full antisubmarine warfare capability; the missile by itself is only a single part of the system.
Iran has promised further revelations of new weapons in the days ahead.
RFE/RL Iran Report
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