Consisting of a radar-guided 20
millimeters 0.8 in vulcan cannon mounted
on a swiveling base, the Phalanx has been
used by the United States Navy and the Naval Forces of 15 other countries.
The US Navy deploys it on every class
of surface combat ship, except the Zumwalt-Class Destroyer and San Antonio-Alass Amphibious transport dock. Other users include the British Royal Navy, the Royal Australian Navy, the Royal New Zealand Navy, the Royal Canadian Navy
and the U.S Coast Guard aboard its
hamilton and legend class cutters.
A land variant known as the lpws or land Phalanx weapon system part of the cram
system has recently been deployed in a
short-range missile defense role, to
counter incoming rockets artillery and
mortar fire.
The US Navy also fields the C-RAM System which pairs the RIM-116 rolling airframe missile with
sensors based on the Phalanx. Because of their distinctive
barrel-shaped redome and their automated
nature of operation, Phalanx CIWS units
are sometimes nicknamed R2D2 after the
famous droid character from the Star Wars films.
The Phalanx Close In Weapon System or CIWS was developed as the last line of
automated weapons defense, terminal
defense or point defense against all
incoming threats, including small boats, surface torpedoes, anti-ship missiles
ashms or asms and attacking aircraft, including high g and maneuvering sea
skimmers.
The first prototype system was offered
to the US Navy for evaluation on the
destroyer leader USS King in 1973 and it
was determined that further work was
required to improve performance and
reliability.
Subsequently, the Phalanx operational
suitability model successfully completed
its Operational Test and Evaluation (OTNE) onboard the destroyer USS Bigelow in
1977. The model exceeded operational
maintenance, reliability and availability
specifications.
Another evaluation
successfully followed and the weapon
system was approved for production in
1978. Phalanx production started with orders
for 23 usn and 14 foreign military
systems.
The first ship fully fitted out was the
aircraft carrier USS Coral sea in 1980. The navy began placing CIWS systems on
non-combatant vessels in 1984.
The basis of the system is the 20
millimeters M-61 Vulcan Gatling Gun Autocannon, used since 1959 by the United States Military on various tactical
aircraft, linked to a coo-band fire
control radar system for acquiring and
tracking targets. This proven system was combined with a
purpose-made mounting, capable of fast
elevation and traverse speeds to track
incoming targets.
An entirely self-contained unit, the
mounting houses the gun, an automated
fire control system and all other major
components, enabling it to automatically
search for detect, track, engage and
confirm kills using its
computer-controlled radar system.
Owing to this self-contained nature
is ideal for support ships which lack
integrated targeting systems and
generally have limited sensors. The entire unit has a mass between 12,400 to 13,500 pounds, 5600 to 6100 kilograms.
Due to the evolution of threats and
computer technology, the Phalanx system
has been developed through several
configurations. the basic, original, style is the block
zero, equipped with first-generation
solid-state electronics and with
marginal capability against surface
targets.
The block 1, 1988 upgrade offered various
improvements in radar, ammunition, computing power, rate of fire and an
increase in maximum engagement elevation
to plus 70 degrees. These improvements were intended to
increase the system's capability against
emerging russian supersonic anti-ship
missiles.
Block 1A introduced a new computer
system to counter more maneuverable
targets. The block 1 BPS Umor Phalanx surface
mode 1999, adds a forward-looking
infrared or flare sensor to make the
weapon effective against surface targets.
This addition was developed to provide
ship defense against small vessel
threats and other, floaters in literal
waters and to improve the weapon's
performance against slower low-flying
aircraft. The flir's capability is also of use
against low observability missiles and
can be linked with the RIM-116 Rolling Airframe Missile or RAM system to increase ram engagement range
and accuracy.
The block 1B also allows for an operator
to visually identify and target threats. Since the end of fiscal year 2015 the
u.s navy has upgraded all Phalanx
systems to the block 1B variant.
In addition to the flir sensor the block
1B incorporates an automatic acquisition
video tracker, Pptimized Gun Barrels or OGB and Enhanced Lethality Cartridges or ELC for additional capabilities against
asymmetric threats such as small
maneuvering surface craft, slow-flying
fixed and rotary-winged aircraft and
unmanned aerial vehicles.
The flare sensor improves performance
against anti-ship cruise missiles. While
the OGB and ELC provide tighter
dispersion and increased first hit range.
The MK-244 ELC is specifically designed
to penetrate anti-ship missiles with a
48 heavier tungsten penetrator round and
an aluminum nosepiece.
Another system upgrade is the Phalanx 1B baseline 2 radar to improve detection
performance, increase reliability and
reduce maintenance. It also has a surface mode to track, detect and destroy threats closer to the
water's surface. Increasing the ability
to defend against fast attack boats and
low-flying missiles.
As of 2019 the baseline 2 radar upgrade
has been installed on all US Navy Phalanx system equipped vessels. The block 1B is also used by other
navies, such as Canada, Portugal, Japan, Egypt, Bahrain and the UK.
In april 2017 Raytheon tested a new
electric gun for the Phalanx, allowing
the system to fire at varying rates to
conserve ammunition. The new design replaces the pneumatic
motor, compressor and storage tanks, reducing system weight by 180 pounds 82
kilograms while increasing reliability
and reducing operating costs.
The CIWS is designed to be the last line
of defense against anti-ship missiles. Due to its design criteria, its effective
range is very short relative to the
range of modern asms, from one to five
nautical miles two to nine kilometers.
The gun mount moves at a very high speed
and with great precision. The system takes minimal inputs from the
ship making it capable of functioning
despite potential damage to the ship.
The only inputs required for operation
are 440 volts AC-3 phase electric power
at 60 hertz and water for electronics
cooling. For full operation, including some
non-essential functions it also has
inputs for ship's true compass heading
and 115 volts AC for the wind pass
subsystem.
Wind pass or windows-based parameter
analysis and storage subsystem is a
secondary computer built into the local
control station that allows technicians
to perform various tests on system
hardware and software for maintenance
and troubleshooting purposes. It also stores data from any engagements
the system conducts so that it can later
be analyzed.
