Over at Strategy Page, they have an in-depth article on the attack on two US warships while anchored in Jordan. And they give a detailed answer to my question about just what kind of a weapon was used.
The 150 pound, 122mm Russian designed BM-21 rocket is nine feet long and has a range of 20 kilometers and a 45 pound warhead. Developed in the late 1930s by Russia, the 122mm rocket is normally fired in large numbers from many launchers at spread-out targets. That’s because the rockets are unguided. Aim lots of them at a target and you’ll hit something. Aim a few of them at something, and you usually won’t, But the rockets are made by many countries, relatively easy to get, and favored by terrorists for attacks that terrorize, rather than actually do any damage.
Now, 45 pounds of high explosive is a bit more than I was figuring when I wrote my piece yesterday, but it changes only a little. A hit would have damaged any exposed systems and killed or injured on-deck personnel, but unless it was very, very lucky it would not have penetrated the hull or deck of the Ashland. Even ships technically “unarmored” have steel hulls, steel or steel-reinforced decks, and steel or aluminum superstructure, and they would most likely have detonated the rocket before it could gotten to the ship’s interior.
The BM-21 rocket is designed to be fired in large numbers in the general direction of the target, in hopes that a couple might come close enough to have an effect. And those targets are “soft” targets — usually infantry and very light vehicles. They were never intended to be used against warships.
Yes, they persuaded the Navy to pull the Ashland and Kearsarge out of port quickly, and ahead of schedule. But what did they achieve beyond minorly inconveniencing the crews of two ships? Absolutely nothing. And what did it cost them? At least six terrorists and four more BM-21 rockets, along with a great deal of displeasure from the Jordanian authorities and people.
Yup, they’ve certainly achieved a great deal with this attack.