CIWS now does surface targets, too

Phalanx Mk 15 CIWS – Block 1B

The recent attack on the US Navy by pirates (successfully fought off, thank goodness) already had me thinking about the latest version of the Phalanx Close In Weapons System (CIWS), and when a commenter at Hell in a Handbasket wondered about the capability of the CIWS to engage surface targets, I decided to do a quick post on the subject.

CIWS, of course was originally designed to defend our ships from high-speed missiles. The six-barrelled 20mm gun is a last-ditch defense against incoming ship killers. Over the years, the original Block 0 models (introduced in 1980) were supplanted by the Block 1(1988) and 1A (1996). Now, the Block 1B (also referred to as “Phalanx Surface Mode” or PSUM) improves on these, and (maybe more importantly) provides for defense against surface targets like small boats and personal watercraft as well as against slower aircraft like helicopters. Forward-Looking IR and video tracking/targeting, Ku-band radar, and longer barrels providing better accuracy are among the most notable improvements over earlier versions. Capability against missiles is unimpeded. Let’s hope that maintenance and combat readiness, long a problem with these units, also improves.

Although it might seem that these improvements might be a response to the suicide attack against USS Cole in 2000, that isn’t the case. Prototypes were tested in 1999 and installation of Block 1B systems, either upgrades of earlier versions or new builds, has been going on since 2000.

For more background information on the Phalanx, see (of all places) the Pakistan Military Consortium.

Earlier model Phalanx (left) vs. Block 1B (right):

ciws.jpg      ciws1b.jpg

Note the FLIR and video tracking systems mounted on the left side of the Block 1B unit.

Here is more detailed info from Raytheon. The source is the .pdf where I found the image above and contains additional background. Here’s the goods on the Block 1B:

The Threat
Today, surface combat is most likely to occur in near shore, littoral environments. This scenario places ships and their crews at risk to an increased number of threats including small, fast gun boats, standard and guided artillery, helicopters, mines and a variety of shore launched anti-ship missiles. These threats demand a new generation of ship defense capabilities – Phalanx Block 1B.

The Solution
Raytheon’s Phalanx Block 1B Surface Mode is a complete weapon system to counter threats of today and tomorrow. With an integrated FLIR and operator control panels merged with a proven anti-ship missile defense capability, the Block 1B system is unique in the world. The system has been thoroughly tested in real world scenarios against a variety of ship defense threats and will soon be deploying on U.S. Navy vessels.

Optimized Gun Barrels
The original M61A1 gun barrels were designed for short bursts and are subject to wear and increased dispersion patterns. The new OGBs are 18 inches longer, substantially thicker and include both a barrel brace and muzzle restraint to improve life expectancy and projectile dispersion patterns. In addition, the optional Enhanced Lethality Cartridge (ELC) will provide a 50 percent increase in penetrator mass.

Phalanx FLIR
To provide its unique Surface Mode tracking and engagement capability, Phalanx Block 1B incorporates a Thermal Imager with Automatic Acquisition Tracking. The system operates in the 8–12 micron wavelength and is mounted on a stabilized pedestal attached to the existing Phalanx Track Antenna radome. This system provides a reliable day/night passive search and track capability against slow-speed air threats and surface craft, while improving Anti Air Warfare performance in multi-path and glint environments via enhanced angular track accuracy (50–100 microradians) against the high-G maneuvering ASM.

Operational Features

  • Autonomous detect, prioritization, track, engagement and kill assessment of air targets from wave-top to steeply diving
  • Day/night detect, identification, track and engagement, and kill assessment of surface craft and low-speed aircraft
  • Remote designation available from other ships’ sensors against air and surface targets
  • Interface and control to provide fire-control and search sensor capability for other shipboard gun and missile systems

Here are a couple of CIWS units pulled from USS Missouri on Wasted Disk Space’s Battleship Missouri Memorial:

It’s a bit unclear to me what the exact status of Missouri’s CIWS systems is. According to the USS Missouri FAQ:

Did Missouri have the Phalanx system on board? Did and do. We sailed in 1986 with four of the Phalanx, CIWS (Close-In Weapons System) units on board. When we decommissioned the Navy took them away to use on other ships and has only given 2 of them back to us (so far).

MO contacted the FAQ admin and found out that the two units have been remounted, one port-forward and one starboard-aft. [UPDATE: The pic above is “almost certainly” the two returned that have been remounted.] They have part of a third unit and continue efforts to get the rest and a fourth unit.

This is the schedule for Block 1B installations according to a recent (Feb 2006) US Navy Budget Item Justification Sheet (.pdf):

FY2006: 20
FY2007: 22
FY2008: 39
FY2009: 32
FY2010: 34
FY2011: 40
(FY2005 & Earlier: 34 total)

Here’s a nifty diagram of the Phalanx family evolution from Block 0 up to the Block 1B (and actually beyond Block 1B and into the SEA RAM program which replaces the 20mm gun with a Sea Sparrow/Sidewinder mongrel missile for greater range…but that’s another post). Click for a better look:

The slide is from an awesome Raytheon .pdf at DTIC from early 2000. Unfortunately, there seem to be a couple of problems with the sheets, particularly with one comparing the accuracy of the older gun barrels with the new ones.

Last but not least, don’t forget the C-RAM (Counter Rocket Artillery Mortar) system, a land-based Phalanx currently in use in Iraq. Here’s a pic:


The C-RAM uses a Block 1B, as you can tell by the FLIR and video gear on the left-hand (far) side of the “R2-D2” dome. I’ve had no word on the the C-RAM since its deployment to the Sand Box last summer. I know for a fact that the military is trying to keep a lid on the actual performance of this beast, so maybe that’s why. Defense Industry Daily noted last fall that Northrup Grumman won a contract for more of the systems, so decision-makers must be optimistic of the C-RAM’s potential regardless of current success.

Also, in my earlier article I wrote that the C-RAM’s HEIT-SD (High-Explosive Incendiary Tracer, Self-Destruct) ammunition “explode[s] in mid-air, raining shrapnel at the incoming rounds in order to destroy or deflect them”, which isn’t the case. The self-destruct feature is really intended to prevent the rounds from falling into friendly areas on the ground and causing damage. At up to 4,500 rounds per minute, that would be some seriously un-friendly fire raining down and would not win many hearts and minds.

Ship-borne Phalanx systems used to use depleted uranium rounds, but more recently have switched to tungsten. So, fish, keep your heads down!

(NOTE: There seems to be a lot of confusion about the “Block 1B” designation which apparently stems from the naming convention of the Block 1 series. Incremental improvements to Block 1 were “Block 1 Baselevel 0”, “Block 1 Baselevel 1”, and “Block 1 Baselevel 2”. These were replaced by the “Block 1A”, which is being supplanted by the “Block 1B” which this post primarily deals with. Look on the Phalanx family slide above and you will see that the Block 1 baselevels are marked “Block 1 B/L 0” and so on, and I think this has some folks thinking that it means “Block 1 B”. It doesn’t.)


  1. Now all it needs is a megaphone so that it can provide appropriate sound effects while engaging: ‘EX… TER… MIN… ATE…. EX… TER… MIN… ATE!’ (A joke a lot of English people would understand but probably not many Americans… oh well)

  2. Just a piece of background on why this was in development prior to USS Cole from someone who spent Sep 87-Sep 88 in the gulf. During Operation Ernest Will (87-88), the Iranian Revolutionary Guard’s Navy illustrated that our cruisers and destroyers had no more effective firepower (in some cases less) against a small boat threat than a frigate. .50 cals and 40mm grenade launchers plus 0-2x 3 or 5 inch guns were all we had on the small boys. Missiles are ineffective and the main guns have a hard time tracking small boats. Add in that the IRGN had a habit of putting WP in their rockets/RPG warheads and that there is no real armor on modern ships…. well it was a problem. These days, in addition to upgraded Mk15’s, M2s, M60s and M19s, we have put 25mm chain guns on the ships. The IRGN is still predomanatly a large brown water small boat force.

  3. Murdoc: I’m only familiar with the old Doctor Who. It seems Daleks survived the transition to the new series. I’d like to watch it but chances are low since I never watch TV. I’m glad to see that aspect, which has haunted me since I was quite young, has survived. Dr. Who may have been low budget in the 70s but it was still scary! dj elliott: Interesting. Maybe it’s time to bring back the old 40mm Bofors single/twin/quad-mount turrets for use against air and surface threats :)

  4. Nicholas: single and twin 40mm Bofors mounts are still used in many navies. Just not ours. Good weaps. Unfortunately there is a tendancy in the procurement section of the pentagon to equate old with obsolete. During the escorts some of our cruisers did not have main guns. Missiles and small arms (later 25mm add ons) only. That has changed since then…

  5. Anyone heard anything new on the idea of putting these on land to knock down incoming mortar or rocket attacks? I know it was discussed, have they gone any further ahead with the idea? I’d think they could put in a manual control with a joystick somewhere. Now how cool would the practice for that be, or God forbid, a 2 second burst on a wooden dhow!

  6. oops, guess I need to read the ‘rest of the story’ before I put in my two cents. Has anyone heard how the C-ram is doing?

  7. Maybe they finally have a version of the Phalanx that works now. The stories I heard about the earlier models were pretty comical. Are those optical sights on the side of the new R2D2? If so, that’s a good addition. A small, low return boat full of explosives would be hard to hit using only radar guidance.

  8. What about the target identification of this system – I guess the reason why the USS Cole did not shoot down the boat would have been for civilian safety in a port. I doubt it can really tell any difference in targets apart from IR/radar signature. I guess it can maybe be set to be limited to a certain engagement limit. Problems would arise in target identification from incoming and outgoing rounds in the land based case. Especially when most needed, ie. when a base is being assaulted and outgoing is as necessary as protecting from incoming. Not too likely to happen, but nevertheless I am sure the insurgents would learn that they no longer get return fire after launching a couple of mortars.

  9. Here’s a related link describing a stabilised .50 calibre setup in use by the Israelis and Australians. I expect there’s quite a bit more of this going on without much publicity:

  10. RE: 40mm Every time I’m on a museum ship from the WW2 era and see all those 40mm quads, I always say to myself ‘Seems we could still be getting a lot of good use out of these things…’ Not those particular weapons, of course, but don’t tell me that the 40mm Bofors can’t still play ball.

  11. FM: Great post! I was unaware of the Mini-Typhoon. Seems to me that the US Navy could put a CROWS or the upcoming stabilized RWS with a .50 cal right on ships right now. Better yet, put the CROWS control system on a 40mm Bofors twin or quad if you’ve got room.

  12. Vsteer… One of the main reasons that the Cole’s CIWS mounts did not respond to the small boat is that the gun was more than likely not on, and was unloaded. I was a tech/supervisor of two CIWS systems on the USS Briscoe (DD-977)during Operation Desert Shield and we ALWAYS had to have the gun totally unloaded, filled with dummy/inert rounds and the system in standby before we entered port…even in the Gulf when we were under an extremely high security level. That may have changed since the Cole situation, but up until then, that was the practice IAW some COMNAVSURFLANT instruction. Also to Murdoc – The ‘sublevels’ are referred to as Baseline, not Baselevel…FYI.

  13. To add to the Cole comments… I am currently the Work Center Sup. for CIWS on board a Cruiser, and have been stationed on a DDG in the Gulf. The last commenter was correct. We generally do have to download all live rounds previous to entering a port. But that applies to Block 1A mounts. And would depend on the Captain’s orders, so would differ from ship to ship. The Block 1B being a completely different beast serves dual purposes, Offensive as well as Defensive, so it may well be that we wouldn’t download before pulling into a foreign port. Also, in Oct of 2000 when the USS Cole was bombed in Yemen, she wasn’t yet equipped with the 1B configuration. She was however one of the first DDG’s to be outfitted with the 1B. I guess as one way to show those that would mean us harm that she will not make the same mistake twice. The CIWS 1B is now equipped on just about all FFG’s as they are used as Anti drug operation ships, and has proven to be a very effective deterrent. You can imagine looking up and seeing the CIWS’s 6 barrels pointing down at you and following your every move a little more than intimidating. This is of course, my opinion. Thanks, regards FC2 Granberg

  14. I’m not trying to get anyone court marshalled or anything(due to sharing classified info), but CHECK THIS OUT! ‘Out of theater’ footage of the C-RAM. Video is almost 2 megs.…cram_video.wmv

    Credit to LockDownSG

  15. I’m sorry to say, but the Goalkeeper of Thales is fare out the best. 30mm rounds (MPDS) 70 rounds per second AHPC (Automatic Hitting Point Correction) And much more…..

  16. I good friend of mine was just sent to Iraq about a week ago as a contractor and he said the area he is staying in has at least one of the C-RAM systems. Well, it went off just the other night and they heard the shrapnel raining down on the tin roof. Seems to be working well. :-)