With nuclear tensions again on the rise, the Iranian government unveiled new weaponry late last week, sending a signal that a potential military attack against its terrtory will come at a price. In one case, the weapon displayed by the Iranians may be less of a threat than first imagined, while the other system may be a cause for some concern.
Let's start with the "new," high-speed Iranian torpedo, which recieved lots of media attention over the weekend. On paper, it appears impressive; using "super-cavitating" technology, it cruises toward its target at speeds in excess of 200 kilometers per hour; its large conventional warhead is large enough to sink a smaller naval combatant, or seriously damage an aircraft carrier. The torpedo, or more accurately, a rocket-propelled torpedo, can be launched from submarines, aircraft, surface vessels, or even shore batterys.
But on closer review, the torpedo is hardly a world-beater. It appears to be a copy of the Russian SHKVEL-3, which has been around for more than a decade. The SHKVEL-3 is essentially an updated copy of a WWII torpedo, with a rocket motor (generating the high speeds necessary for super-cavitation), and a giant warhead. The torpedo does not have any sort of active, onboard sonar or any other homing device. Rather, it requires a pre-calculated "firing solution," which sends the torpedo to a predicted collision course with the target.
If you've watched any WWII submarine movie, you've got some idea of how it works. By determining the target's bearing, speed and distance, a computer develops a firing solution, which determines the course for the torpedo. But there's only one problem: any changes by the target in speed, course, or distance screws up the firing solution, and greatly increases the probability of a miss, even in salvo launches. And, making matters worse, the SHKVEL-3 (and its Iranian cousin) have fairly short legs; in other words, the launch platform needs to press in close to launch the weapon. Unfortunately for the Iranians, the U.S. Navy has a multi-layered air, ASW and surface screen that extends miles beyond the carrier. Pressing in close for a SHKVEL-3 attack would be a suicide mission for an Iranian P-3, Kilo-class sub, or surface vessel.
The torpedo threat cannot be dismissed, but it's not going to keep the U.S. Navy from operating carrier battle groups inside the Strait of Hormuz, either. On the other hand, Iran's test of a "radar evading" missile may be more cause for concern. Last week, Tehran announced a successful test of a Fajir-3 surface-to-surface missile, which (according to an Iranian spokesman) can evade enemy missile defenses. I believe the Fajir-3 designator is a misnomer, or an effort at deception by Iran.
First of all, the Fajir-3 designator is assigned to an Iranian battlefield rocket that has been in service for several years. Battlefield rockets (such as the Russian FROG-7) are area weapons, not intended for precision targeting. They are often launched in salvoes aimed at enemy troop concentrations, staging areas, port facilities and airfields, and often carry chemical weapons, so accuracy is less important. And, because these weapons are produced on a larger scale than ballistic missiles, it makes little sense to give these weapons a radar evading or stealth capability.
If Iran were interested in deploying that type of technology, they would likely add the technology to one of their SHAHAB series missiles, such as the SHAHAB-2 (their version of the SCUD), or the medium-range SHAHAB-3, which is capable of hitting Israel. With the recent deployment (and successful testing) of Israel's anti-missile shield (the Arrow II system), Tehran would like to have some way to increase its chances of penetrating Israeli defenses, and having some assurance of scoring a hit. There are a variety of ways that Iran could develop that sort of capability for its guided missiles, including decoys (which deploy along with the re-entry vehicle (RV)for the warhead), a stealthier RV design, or some sort of radar-absorbing shroud for the RV assembly. Successful implementation of any of these measures would make it more difficult to detect and engage an incoming Iranian missile.
We will probably learn more about these Iranian systems in the coming days. In both cases, these weapons are likely in the developmental stage, so any sort of large-scale deployment may be years away. That gives us even more time to determine the exact nature of the threat, and develop optimum counter-tactics and systems. Tehran's military got a lot of press attention over the weekend, but (so far) they haven't demonstrated anything that would alter the balance of military power in the region.