DESIGNATOR :        Mk 15/16 
                    20-mm/76-calibaer CLOSE IN WEAPON SYSTEM 
                    (CIWS) 
NAME:               PHALANX GATLING GUN 
 
DESCRIPTION:   The Phalanx is a self-contained, shipboard self-defense gun using 
a modified M61 Vulcan six-barrel Gatling cannon, built-in pulse-doppler J-band 
fire control radar, and digital computer.  It is intended to treat attacking 
anti-ship missiles. 
    The US Navy uses the designations mk 15 and Mk 16 to refer to CIWS. 
 
STATUS: Initial operational capability 1980.  In production by Pomona Division, 
General Dynamics Corp., Pomona Calif..  General Electric has a contract to 
qualify as second source for the system and is the supplier of all M61 guns.  In 
service in some 200 US ships with plans to equip 250. Also in service with 
several foreign navies. 
 
 
USERS/PLATFORMS 
USA 
  NAVY              Aircraft Carriers (3-4 mounts) 
                    Battleships (4) 
                    Cruisers (2) 
                    Destroyers (2) 
                    Frigates (1) 
                    Amphibious Command Ships (2) 
                    Helicopter Carriers (1-2) 
                    Amphibious Transport Docks (2) 
                    Dock Landing Ships (2) 
                    Tank Landing Ships (1) 
                    Ammunition Ships (2) 
                    Combat Stores Ships (2) 
                    Combat Support Ships (2) 
                    Replenishment Oilers (1) 
Coast Guard         High-endurance Cutters (1) 
 
Australia           Great Britain       Japan          Canada 
Israel              Saudia Arabia 
 
CHARACTERISTICS: 
Weight, Mount       12,000 lbs (5,443) 
Armament 
     Elevation      +90 deg 
Performance: 
   Maximum range    1,625 yd (1,486 m) 
   Rate Of Fire     3,000 rpm theoretical maximum 
   Muzzle velocity  3,280 fps (1,000 mps) 
   Reaction time    2 seconds from threat detection 
   Projectile       Mk 149 sub-caliber (12.75 mm) depleted uranium 
                    Penetrator 2 1/2 times as dense as steel within a 
                    nylon sabot and spun initially by an aluminum "pusher". 
   Magazine Capacity 
     Mod 0 Block 0  980 rounds 
           Block 1  Approximately 1,450 rounds 
Fire Control 
   VPS-2 Pulse-doppler, J-band search and track radar with close-loop 
    spotting which follows both target and its own 20-mm projectiles. 
   High-speed digital computer automatically engages incoming, high speed 
    Threat unless countermanded by the operator. 
Crew 
   Unmanned 
Protection 
   Weather protection for mount radar 
 
VARIANTS: 
   BLOCK 1:   Has improved radar with four-plate back-to-back search array for 
high-elevation coverage, greater ammunition stowage, higher rate of fire, and 
enhanced reliability and maintainability. Authorization for limited production 
in 1986 
 
ISSUES:  The installation of Phalanx CIWS came several years after the 
appearance of similar rapid-fire gun systems of larger caliber, in Soviet 
surface warships.  Most foreign CIWS designs include 25-mm or 30-mm rapid- fire 
gun rather than the smaller 20-mm of the Phalanx. 
 
PROGRAM ACQUISITION COSTS (IN MILLIONS) 
 
                  Actual         Proposed           Proposed 
                   FY87            FY88               FY89 
 
Procurement     (24) 102.2      (5)  28.1          (5)  19.4 
Initial Spares         1.8            1.6                1.1 
RDT&E                  5.3            7.6               11.9 
Military Construction ----           ----               ---- 
 
             Totals  109.3           37.3               32.4 
 
Unit Costs (FY1988) $5,604,600 
 
OPERATIONAL NOTES:  The CIWS on the USS STARK (FFG31) did not engage the 
French-Built Exocet AM-39 air-to-surface missiles launched against the ship by 
an Iraqi aircraft on 17 May 1987. 
  In Senate Hearings before the Committee on Appropriations for FY1986, US 
Department of Defense officials were asked about the effectiveness of the CIWS 
against Exocet missiles, to which they replied, "In Recent operational tests, 
PHALANX destroyed numerous EXOCETS in an imparessive4 fashion." 
