Patriot is a long-range, all-altitude, all-weather air defence system to counter tactical ballistic missiles, cruise missiles and advanced aircraft. Patriot (MIM-104) is produced by Raytheon in Massachusetts and Lockheed Martin Missiles and Fire Control in Florida.
As well as
the US, Patriot is in service in Egypt, Germany, Greece, Israel, Japan,
Kuwait, the Netherlands, Saudi Arabia and Taiwan.
systems were deployed by US forces during Operation Iraqi Freedom. The
systems were stationed in Kuwait and successfully destroyed a number of
hostile surface-to-surface missiles, using the new PAC-3 and guidance
Guidance enhanced missile (GEM-T) upgrade.
Patriot missile is equipped with a track-via-missile (TVM) guidance
system. Midcourse correction commands are transmitted to the guidance
system from the mobile engagement control centre.
The target acquisition system in the missile acquires the target in
the terminal phase of flight and transmits the data using the TVM
downlink via the ground radar to the engagement control station for
final course correction calculations. The course correction commands are
transmitted to the missile via the missile track command uplink. The
high-explosive 90kg warhead is situated behind the terminal guidance
The range of the missile is 70km and maximum altitude is
greater than 24km. The minimum flight time is the time to arm the
missile, which is less than nine seconds, and the maximum flight time is
less than three and a half minutes.
Raytheon has developed the
Patriot guidance enhanced missile (GEM-T), an upgrade to the PAC-2
missile. The upgrade involves a new fuse and the insertion of a new low
noise oscillator, which increases the seeker's sensitivity to low radar
The GEM-T missile provides an upgraded
capability to defeat air-breathing, cruise and ballistic missiles, as a
complement to the PAC-3 missile. The first upgrade forebodies were
delivered to the US Army in November 2002.
By September 2010, a total of 1,000 Patriot missiles were upgraded for the US Army.
July 2008, South Korea placed an order for 64 GEM-T upgrade kits. In
April 2011, US Army Aviation and Missile Command awarded a $58.3m
contract to upgrade 131 PAC-2 missiles to GEM-T missile configuration.
In July 2008, South Korea placed an order for 64 GEM-T upgrade kits.
Patriot advanced capability (PAC-3) missile.
A new Patriot
advanced capability (PAC-3) missile has increased effectiveness against
tactical ballistic and cruise missiles, through the use of advanced
hit-to-kill technology. Lockheed Martin is the prime contractor, with
Raytheon the systems integrator. The PAC-3 has a Ka-band millimetre wave
seeker developed by Boeing.
The missile guidance system enables
target destruction through the kinetic energy released by hitting the
target head-on. 16 PAC-3 missiles can be loaded on a launcher, compared
to four PAC-2 missiles.
PAC-3 entered low rate initial production in late 1999 and first LRIP
production missiles of a total of 92 were delivered in September 2001. A
contract for 88 missiles was placed in December 2002 and another for 12
in March 2003.
The missile was first deployed during Operation
Iraqi Freedom in March / April 2003. In February 2004, Lockheed Martin
was awarded a production contract for 159 PAC-3 missiles, which includes
22 missiles to replace those expended in Iraq. Deliveries were
concluded by April 2006.
A further contract for 156 missiles was
received in February 2005. Of these missiles, 32 are for the Netherlands
and 16 for Japan, under foreign military sales (FMS) agreements. The
Netherlands received the first PAC-3 missiles in October 2007. The US
Army ordered another 112 missiles in May 2006 and 112 in March 2007.
PAC-3 missile segment enhancement (MSE)
The PAC-3 missile segment enhancement (MSE) is part of a spiral development being undertaken by Lockheed Martin.
increased range MSE gives the missile a more powerful rocket motor for
added thrust and larger fins for increased manoeuvrability against
faster and more sophisticated ballistic and cruise missiles. The MSE
began flight testing in May 2008.
The PAC-3 MSE is the baseline
interceptor for the multinational medium extended air defence system
(MEADS) under a contract placed in February 2008. The missile was
successfully test fired using the Patriot system in May 2011. Lockheed
Martin was awarded a $68.9m contract in July 2012 to prepare the PAC-3
production line for the PAC-3 MSE missile.
The PAC-3 MSE successfully destructed a tactical ballistic missile (TBM) target at White Sands Missile Range in December 2012.
M901 launching station transports, points and launches the Patriot
missile. Each launcher has four missiles. The launcher is remotely
operated via a VHF or fibre-optic data link from the engagement control
station, which provides both the missile prelaunch data and the fire
Engagement control station
engagement control station is the only manned station in a Patriot fire
unit. The control station communicates with the M901 launching stations,
with other Patriot batteries and the higher command headquarters.
control station is manned by three operators, who have two consoles and
a communications station with three radio relay terminals. The digital
weapon control computer is located next to the VHF data link terminals.
AN/MPQ-53 phased array radar carries out search, target detection,
track and identification, missile tracking and guidance and electronic
counter-countermeasure (ECCM) functions. The radar is mounted on a
trailer and is automatically controlled by the digital weapons control
computer in the engagement control station, via a cable link. The radar
system has a range of up to 100km, capacity to track up to 100 targets
and can provide missile guidance data for up to nine missiles.
US Army Patriot radars are being upgraded by Raytheon. The upgrade kits
provide greater power for the radar and the addition of a wideband
capability for improved target discrimination.
A target engagement
can be carried out in manual, semi-automatic or automatic mode. When
the decision has been made to engage the target, the engagement control
station selects the launch station or stations and pre-launch data is
transmitted to the selected missile. After launch, the Patriot missile
is acquired by the radar.
The command uplink and the TVM downlink
allow the missile's flight to be monitored and provide missile guidance
commands from the weapon control computer. As the missile approaches the
target, the TVM guidance system is activated and the missile is steered
towards the target. A proximity fuse detonates the high-explosive