Type 81 Surface-to-Air Missile
Encyclopedia
The Type 81 Surface-to-Air Missile or Tan-SAM is a Japan
ese developed surface-to-air missile
currently in service with the Japan Self-Defense Forces
.
as a replacement for the 75 mm M51 Skysweeper
and M15A1 37 mm/12.7 mm
anti-aircraft guns. Designed as a mobile short-range system to fill the performance gap between the FIM-92 Stinger
man portable missile, and the larger MIM-23 Hawk
missile system, which were both in service at the time. Development work began in 1966, with the first test firings conducted in 1978. The system was designated as the Type 81 by the JSDF, and contracts were placed for the system in 1980. The system entered service in 1981. In 1987, minor changed system SAM-1B was designated.
Development work on an upgrade designated Tan-SAM kai started in 1989. Upgraded system was designated as SAM-1C in 1995, initial production on upgrade kits for the system starting in 1996. Two fire units were scheduled to be upgraded in 2000, with work on the program continuing into 2006.
Development work on an upgrade designated Tan-SAM kai II started in 2005.
2.4. It is initially inertially guided to a likely intercept point, with an all-aspect
infra-red seeker taking over to handle terminal guidance. The missile has a 9.2-kilogram fragmentation warhead triggered either by contact or a radar proximity fuze with a lethal radius of between 5 and 15 meters depending on the target type.
A fire unit consists of one Fire Control System vehicle and two launcher vehicles as well as a number of support vehicles with a total crew of fifteen men. The Fire Control Systems vehicle consists of an Isuzu Motors
6×6 truck with a 30 kW generator unit mounted behind the driver's cabin, and a rectangular three-dimensional pulse-doppler phased array radar. The radar can operate in three modes: omni-directional search, sector search/course tracking mode, and fine tracking mode. The radar is scanned both mechanically and electronically and can track up to six targets within the same 110-degree arc in course tracking mode. Two targets can be tracked in fine tracking mode at greater accuracy, with the single-shot kill probability for each target relayed to the operator via a CRT display
. The radar has a range of about 30 kilometers, and has built in IFF capabilities.
Information on the two selected targets is then passed to the two attached launcher units, which are also mounted on Isuzu Motors 6×6 trucks, which slew and elevate their launchers toward the target. The launchers can be deployed up to 300 meters away from the Fire Control System vehicle. An intercept course is computed for the missile, and the missile is launched. The missile follows the initial inertial course until it reaches a pre-programmed point where it activates its infrared seeker. The infrared seeker only scans a programmed area of the sky to prevent it from locking onto the sun. From that point it switches to passive infrared homing for the terminal phase of the flight.
The infrared seeker does not use IR filters to reject decoys, although there is a degree of protection provided by the use of intermediate frequency seeker scanning pattern.
Each launcher is equipped with an optical director than can be used instead of the radar in a high ECM environment or if the radar is not operational; additionally the vehicle can be mounted with one or two 12.7 mm calibre heavy machine gun
s. The system can be set up in approximately 30 minutes, and the launcher reload time for all four missiles is around three minutes.
SAM-1C upgraded missile use a phased array active radar seeker, with the capability of receiving mid-course guidance updates from the Fire Control Systems vehicle. The upgrade also increases the missiles maximum range to 14 kilometers while increasing the missile weight to 105 kilograms. A new smokeless motor with improved thrust is also fitted, replacing the existing motor. Also the Fire Control Systems vehicle is fitted with a thermal imager to improve operation in an ECM
heavy environment.
, JASDF
and JMSDF
with 57 fire units serving with the ground force, 30 serving with the air force, and 6 serving with the maritime force.
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
ese developed surface-to-air missile
Surface-to-air missile
A surface-to-air missile or ground-to-air missile is a missile designed to be launched from the ground to destroy aircraft or other missiles...
currently in service with the Japan Self-Defense Forces
Japan Self-Defense Forces
The , or JSDF, occasionally referred to as JSF or SDF, are the unified military forces of Japan that were established after the end of the post–World War II Allied occupation of Japan. For most of the post-war period the JSDF was confined to the islands of Japan and not permitted to be deployed...
.
Development
The system was developed by ToshibaToshiba
is a multinational electronics and electrical equipment corporation headquartered in Tokyo, Japan. It is a diversified manufacturer and marketer of electrical products, spanning information & communications equipment and systems, Internet-based solutions and services, electronic components and...
as a replacement for the 75 mm M51 Skysweeper
Skysweeper
Skysweeper was an anti-aircraft gun deployed in the early 1950s by both the U.S. Army and U.S. Air Force...
and M15A1 37 mm/12.7 mm
M3 Half-track
The Carrier, Personnel Half-track M3 was an armored vehicle used by the United States, the British Empire and the other Allies during World War II and the Cold War. Nearly 43,000 were produced, and supplied to the U.S...
anti-aircraft guns. Designed as a mobile short-range system to fill the performance gap between the FIM-92 Stinger
FIM-92 Stinger
The FIM-92 Stinger is a personal portable infrared homing surface-to-air missile , which can be adapted to fire from ground vehicles and helicopters , developed in the United States and entered into service in 1981. Used by the militaries of the U.S...
man portable missile, and the larger MIM-23 Hawk
MIM-23 Hawk
The Raytheon MIM-23 Hawk is a U.S. medium range surface-to-air missile. The Hawk was initially designed to destroy aircraft and was later adapted to destroy other missiles in flight. The missile entered service in 1960, and a program of extensive upgrades has kept it from becoming obsolete. It was...
missile system, which were both in service at the time. Development work began in 1966, with the first test firings conducted in 1978. The system was designated as the Type 81 by the JSDF, and contracts were placed for the system in 1980. The system entered service in 1981. In 1987, minor changed system SAM-1B was designated.
Development work on an upgrade designated Tan-SAM kai started in 1989. Upgraded system was designated as SAM-1C in 1995, initial production on upgrade kits for the system starting in 1996. Two fire units were scheduled to be upgraded in 2000, with work on the program continuing into 2006.
Development work on an upgrade designated Tan-SAM kai II started in 2005.
Description
The Tan-SAM 1 missile is cruciform in cross section with four clipped delta wings attached to the mid body, and four small steerable clipped delta fins at the rear of the missile. The missile is propelled by a solid rocket motor, with giving it a burn-out velocity of about MachMach number
Mach number is the speed of an object moving through air, or any other fluid substance, divided by the speed of sound as it is in that substance for its particular physical conditions, including those of temperature and pressure...
2.4. It is initially inertially guided to a likely intercept point, with an all-aspect
All-aspect
An all-aspect missile is one which is able to track a target no matter which way the target faces relative to the missile. In other words, an all-aspect missile can be launched against a target in a tail-chase engagement, in a head-on engagement, in a side-on engagement, from above, from below,...
infra-red seeker taking over to handle terminal guidance. The missile has a 9.2-kilogram fragmentation warhead triggered either by contact or a radar proximity fuze with a lethal radius of between 5 and 15 meters depending on the target type.
A fire unit consists of one Fire Control System vehicle and two launcher vehicles as well as a number of support vehicles with a total crew of fifteen men. The Fire Control Systems vehicle consists of an Isuzu Motors
Isuzu
, is a Japanese car, commercial vehicle and heavy truck manufacturing company, headquartered in Tokyo. In 2005, Isuzu became the world's largest manufacturer of medium to heavy duty trucks. It has assembly and manufacturing plants in the Japanese city of Fujisawa, as well as in the prefectures...
6×6 truck with a 30 kW generator unit mounted behind the driver's cabin, and a rectangular three-dimensional pulse-doppler phased array radar. The radar can operate in three modes: omni-directional search, sector search/course tracking mode, and fine tracking mode. The radar is scanned both mechanically and electronically and can track up to six targets within the same 110-degree arc in course tracking mode. Two targets can be tracked in fine tracking mode at greater accuracy, with the single-shot kill probability for each target relayed to the operator via a CRT display
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
. The radar has a range of about 30 kilometers, and has built in IFF capabilities.
Information on the two selected targets is then passed to the two attached launcher units, which are also mounted on Isuzu Motors 6×6 trucks, which slew and elevate their launchers toward the target. The launchers can be deployed up to 300 meters away from the Fire Control System vehicle. An intercept course is computed for the missile, and the missile is launched. The missile follows the initial inertial course until it reaches a pre-programmed point where it activates its infrared seeker. The infrared seeker only scans a programmed area of the sky to prevent it from locking onto the sun. From that point it switches to passive infrared homing for the terminal phase of the flight.
The infrared seeker does not use IR filters to reject decoys, although there is a degree of protection provided by the use of intermediate frequency seeker scanning pattern.
Each launcher is equipped with an optical director than can be used instead of the radar in a high ECM environment or if the radar is not operational; additionally the vehicle can be mounted with one or two 12.7 mm calibre heavy machine gun
Heavy machine gun
The heavy machine gun or HMG is a larger class of machine gun generally recognized to refer to two separate stages of machine gun development. The term was originally used to refer to the early generation of machine guns which came into widespread use in World War I...
s. The system can be set up in approximately 30 minutes, and the launcher reload time for all four missiles is around three minutes.
SAM-1C upgraded missile use a phased array active radar seeker, with the capability of receiving mid-course guidance updates from the Fire Control Systems vehicle. The upgrade also increases the missiles maximum range to 14 kilometers while increasing the missile weight to 105 kilograms. A new smokeless motor with improved thrust is also fitted, replacing the existing motor. Also the Fire Control Systems vehicle is fitted with a thermal imager to improve operation in an ECM
Electronic countermeasures
An electronic countermeasure is an electrical or electronic device designed to trick or deceive radar, sonar or other detection systems, like infrared or lasers. It may be used both offensively and defensively to deny targeting information to an enemy...
heavy environment.
Deployment
The system is currently deployed by the JGSDFJapan Ground Self-Defense Force
The , or JGSDF, is the army of Japan. The largest of the three services of the Japan Self-Defense Forces, the Ground Self-Defense Force operates under the command of the chief of the ground staff, based in the city of Ichigaya, Tokyo. The present chief of ground staff is General Yoshifumi Hibako...
, JASDF
Japan Air Self-Defense Force
The , or JASDF, is the aviation branch of the Japan Self-Defense Forces responsible for the defense of Japanese airspace and other aerospace operations. The JASDF carries out combat air patrols around Japan, while also maintaining an extensive network of ground and air early warning radar systems...
and JMSDF
Japan Maritime Self-Defense Force
The , or JMSDF, is the naval branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. It was formed following the dissolution of the Imperial Japanese Navy after World War II....
with 57 fire units serving with the ground force, 30 serving with the air force, and 6 serving with the maritime force.