December 25, 2007: Israel is desperate
for a weapon that will defend key targets from Palestinian rockets fired from
Gaza. There have been lots of proposals, and some new defensive systems are in
development. Then some Israelis noted that the American and British were
already using an effective anti-rocket system; C RAM. This is a modified
version of the U.S. Navy Phalanx system, which¬†
was originally designed to protect warships from anti-ship missiles. As
originally designed, you turned Phalanx on whenever the ship was likely to have
an anti-ship missile fired at it. The Phalanx radar can spot incoming missiles
out to about 5,000 meters, and the 20mm cannon is effective out to about 2,000
meters. With incoming missiles moving a up to several hundred meters a second,
you can see why Phalanx is set to automatic. There's not much time for human
intervention, which is why the Phalanx has to be turned on and set to
automatically detect and shoot at incoming missiles. But weapons engineers
discovered that Phalanx could take out incoming 155mm artillery shells as well.
This capability is what led to C-RAM.
Since 2003, there have been two major
Phalanx mods. In one, the Phalanx was adapted to use on land, to shoot down
incoming¬† rockets. This was done by using
a larger artillery spotting radar, which directs Phalanx to¬† fire at incoming mortar shells and rockets.
Not all the incoming stuff is hit, but a lot of it is, and every little bit
helps. The second mod is for shipboard use, and changes the software so the
Phalanx can be used against small boats, especially those of the suicide bomber
Last year,¬† Israel examined C RAM for possible use in
defending northern Israel against another Hizbollah rocket attack. That's where
Israelis apparently became aware of how C RAM could be used against Palestinian
attacks using more primitive rockets. ¬†For defending northern Israel, C-RAM lacked
the range to cover a long border against a variety of rocket types. But the
home made Palestinian rockets fired from Gaza were another matter. Then, earlier
this year, Britain bought a C RAM system to protect its air base in southern
C-RAM uses high explosive 20mm shells,
that detonate near the target, spraying it with fragments. By the time these
fragments reach the ground, they are generally too small to injure anyone. The
original Phalanx used 20mm depleted uranium shells, to slice through incoming
missiles. Phalanx fires shells at the rate of 75 per second. Another advantage
of C-RAM, is that it makes a distinctive noise when firing, warning people
nearby that a mortar or rocket attack is underway, giving people an opportunity
to duck inside if they are out and about.
The first C-RAM was sent to Iraq in
late 2006, to protect the Green Zone (the large area in Baghdad turned into an
American base). It was found that C-RAM could knock down 70-80 percent of the
rockets and mortar shells fired within range of its cannon. Not bad, since it only
took about a year to develop C-RAM. Meanwhile, another version, using a
high-powered laser, instead of the 20mm gun, is in development.
Israel has several small targets it
wants to defend in southern Israel. There is the town of Sderot. Since 2001,
nearly 2,000 Kassam (homemade) Palestinian rockets have been fired at Sderot.
Nine people have been killed, and about fifty injured. The Israeli army has
developed a radar system that provides 10-15 seconds warning, which is enough
time to duck into a shelter. But Sderot only has 80 bomb shelters, most of them
built 20-30 years ago and in need of repair. If you want to reduce the
casualties in Sderot (about one dead or wounded per 30-40 rockets fired), you
need to reduce the number of rockets landing. ¬†One C RAM system can defend an area about two
kilometers in diameter. This makes it possible to defend Sderot with one or two
Phalanx guns, and one radar. There's also a power plant and air force base in
the south that could eventually be within range of larger Kassam rockets. One
or two C RAM Phalanx guns at each would greatly reduce the risk of a Kassam
doing any damage.
There are nearly 900 Phalanx systems in
use, most have not gotten these software mods, that enable the cannot to knock
down rockets and shells, as well as incoming anti-ship missiles..