The Blue Font is another person's response to the current topic here from another web site.
Sigh....The press release about the sonar-evading, fast, underwater missile is either mis-translated, garbled, or just plain wrong. It looks to me like the capabilities of the new missile and the new torpedo have been mixed together. I’ll give the reasons point by point.
Quote:
Originally Posted by zeerak
TEHRAN (Reuters) - Iran has test-fired a sonar-evading underwater missile that can outpace any enemy warship, a senior naval commander told state television on Sunday during a week of war games in the Gulf.
You can’t "evade" SONAR like you do RADAR.
There are two types of SONAR. Active SONAR is like RADAR, your transmitter sends out a pulse of sound that bounced off of the target and back to a receiver. You can evade this the same way you do RADAR by absorbing or misdirecting the pulse of sound. Many submarines have special coverings for exactly this purpose.
The second type of SONAR, however, is passive. It is simply listening to the sounds made by the target itself. These can be engine or motor sounds, active SONAR pulses, or simply flow noise. Nobody uses active SONAR to track torpedoes, there is no reason to. Torpedoes make an enormous amount of noise with their engines, their high-speed transit, and their active sonar. There is no way to "evade" this.
It is possible to make a torpedo go slowly and quietly in an attempt to sneak up on its target for a while, especially when the torpedo is still far away and the worse the sonar on the target, the better this will work, but this also isn’t "evading SONAR".
Quote:
Originally Posted by zeerak
"This missile evades sonar technology under the water and even if the enemy sonar system could detect its movement under the water, no warship could escape from it because of its high velocity," Revolutionary Guards Rear Admiral Ali Fadavi said.
All modern torpedoes have higher top speeds then their targets, it would be pointless to make them otherwise. But they have a much smaller range than their targets. The higher the speed, the lower this range is. A submarine has to move away fast enough that the torpedo runs out of fuel before it hits. It is the torpedoes range/endurance envelope that is important, not it’s maximum speed (although a fast speed certainly helps). The phrase "no warship could escape from it because of its high velocity" simply makes no sense. It is like saying that nobody in the world could escape my rifle because the bullet goes faster than a man can run.
Quote:
Originally Posted by zeerak
"The Islamic Republic is now among the only two countries who hold this kind of missile. Under the water the maximum speed that a missile could (usually) move is 25 meters per second, but now we possess a missile which goes as fast as 100 meters per second," he told state television.
The energy required to move through the water goes up to the cube in the increase of speed. In other words if the torpedo really does go 100 m/s, it will need 64 times as much power to push it through the water and will use 64 times as much energy (and probably fuel) as one going 25 m/s. I highly, highly doubt the torpedo goes this fast. It is physically possible to put an engine in the torpedo to make it go this fast, but then you have little room for fuel or explosives. If it does go this fast, you wouldn’t have the range to hit anything.
Quote:
Originally Posted by zeerak
"The boats that can launch this missile have a technology that makes them stealthy and nobody could recognize them or act against them," he added.
All submarines are stealthy, it is what allows them to live. All submarines have the ability to find other stealthy submarines. It is simply a matter of who has the best equipment and the best training. If you are better you find the enemy first and at a longer range. For reasons I will not get in to, US nuclear submarines have little difficulty engaging and destroying non-nuclear submarines. The one exception is when the non-nuclear submarine gets lucky and accidentally finds itself in a good firing position, rather like a manned mine. This is not an unreasonable occurrence in the constricted waters of the Persian Gulf and it is what makes the non-nuclear submarine dangerous. But as far as not being able to "act against them", I know the boat and crew I was in certainly could.
It sounds like Iran has a new torpedo to go with their new submarine. This is certainly a great increase in Iran’s military might, especially in a tight shipping area like the Persian Gulf. There is no need for Iran to exaggerate it’s capabilities in this way. It actually decreases the military deterrent because it reduces the credibility of their other claims.
This is what I pulled off a Message Board in regards to this. It seems like this guy knows from experience.
