Tomahawk (missile)

The Tomahawk (US /ˈtɑːməhɔːk/ or UK /ˈtɒməhɔːk/) is a long-range, all-weather, subsonic cruise missile named after the Native American axe. Introduced by McDonnell Douglas in the 1970s, it was initially designed as a medium to long-range, low-altitude missile that could be launched from a surface platform. It has been improved several times, and due to corporate divestitures and acquisitions, is now made by Raytheon. Some Tomahawks were also manufactured by General Dynamics (now Boeing Defense, Space & Security).^[3][4]

Description

The Tomahawk missile family consists of a number of subsonic, jet engine-powered missiles designed to attack a variety of surface targets. Although a number of launch platforms have been deployed or envisaged, only sea (both surface ship and submarine) launched variants are currently in service. Tomahawk has a modular design, allowing a wide variety of warhead, guidance, and range capabilities.

Variants

There have been several variants of the BGM-109 Tomahawk employing various types of warheads.

• BGM-109A Tomahawk Land Attack Missile – Nuclear (TLAM-A) with a W80 thermonuclear weapon. Retired from service sometime between 2010 and 2013.^[2]
• RGM/UGM-109B Tomahawk Anti Ship Missile (TASM) – active radar homing anti-ship missile variant; withdrawn from service in the 1990s.
• BGM-109C Tomahawk Land Attack Missile – Conventional (TLAM-C) with a unitary warhead. This was initially a modified Bullpup warhead.
• BGM-109D Tomahawk Land Attack Missile – Dispenser (TLAM-D) with cluster munitions.
• RGM/UGM-109E Tomahawk Land Attack Missile (TLAM Block IV) – improved version of the TLAM-C.
• BGM-109G Ground Launched Cruise Missile (GLCM) – with a W84 nuclear warhead; withdrawn from service in 1987.
• AGM-109H/L Medium Range Air to Surface Missile (MRASM) – a shorter range, turbojet powered ASM with cluster munitions ; never entered service, cost US$569,000 (1999).^[5]

Ground-launched cruise missiles (GLCM) and their truck-like launch vehicles were employed at bases in Europe; they were withdrawn from service to comply with the 1987 Intermediate-Range Nuclear Forces Treaty. Many of the anti-ship versions were converted into TLAMs at the end of the Cold War. The Block III TLAMs that entered service in 1993 can fly farther and use Global Positioning System (GPS) receivers to strike more precisely. Block III TLAM-Cs retain the DSMAC II navigation system, allowing GPS only missions, which allow for rapid mission planning, with some reduced accuracy, DSMAC only missions, which take longer to plan but terminal accuracy is somewhat better, and GPS aided missions which combine both DSMAC II and GPS navigation which provides the greatest accuracy. Block IV TLAMs are completely redesigned with an improved turbofan engine. The F107-402 engine provided the new BLK III with a throttle control, allowing in-flight speed changes. This engine also provided better fuel economy. The Block IV TLAMs have enhanced deep-strike capabilities and are equipped with a real-time targeting system for striking fleeting targets. Additionally, the BLOCK IV missiles have the capabilities to be re-targeted inflight, and the ability to transmit, via satcom, an image immediately prior to impact to assist in determining if the missile was attacking the target and the likely damage from the attack.

Upgrades

UGM-109 Tomahawk missile detonates above a test target, 1986

A major improvement to the Tomahawk is network-centric warfare-capabilities, using data from multiple sensors (aircraft, UAVs, satellites, foot soldiers, tanks, ships) to find its target. It will also be able to send data from its sensors to these platforms. It will be a part of the networked force being implemented by the Pentagon.

The "Tactical Tomahawk" takes advantage of a loitering feature in the missile's flight path and allows commanders to redirect the missile to an alternative target, if required. It can be reprogrammed in-flight to attack predesignated targets with GPS coordinates stored in its memory or to any other GPS coordinates. Also, the missile can send data about its status back to the commander. It entered service with the US Navy in late 2004. The Tactical Tomahawk Weapons Control System (TTWCS) added the capability for limited mission planning on board the firing unit (FRU).

In 2012, the USN studied applying Advanced Anti-Radiation Guided Missile (AARGM) technology into the Tactical Tomahawk.^[6]

In February 2014, the U.S. Navy began working on a bunker-busting warhead for the Tomahawk. Called the Joint Multi-Effects Warhead System (JMEWS), it would weigh 3,500 lb (1,600 kg) and be compatible with existing Block IV missiles.^[7]

In 2014, Raytheon began testing Block IV improvements to attack sea and moving land targets.^[8] The new passive radar seeker will passively pick up the electromagnetic radar signature of a target and follow it, and actively send out a signal to bounce off potential targets before impact to discriminate its legitimacy before impact.^[7] Mounting the multi-mode sensor on the missile's nose would remove fuel space, but company officials believe the Navy would be willing to give up space for the sensor's new technologies.^[9] The new seeker could make the Tomahawk a candidate for the U.S. Navy's Offensive Anti-Surface Warfare (OASuW) Increment II requirement. The previous Tomahawk Anti-Ship Missile, retired over a decade ago, was equipped with inertial guidance and the seeker of the Harpoon (missile) and there was concern with its ability to clearly discriminate between targets from a long distance, which would be more reliable with the new seeker's passive detection and active millimeter-wave radar;^[10] the Tomahawk would likely compete against a version of the Lockheed Martin Long Range Anti-Ship Missile for ship-launched needs.^[11]

Raytheon is planning to offer to perform the upgrades as the older Block IVs are brought back to the factory for recertification around 2018.^[12]

A supersonic version of the Tomahawk is under consideration for development with a ramjet to increase its speed to Mach 3. A limiting factor to this is the dimensions of shipboard launch tubes. Instead of modifying every ship able to carry cruise missiles, the ramjet-powered Tomahawk would still have to fit within a 21-inch diameter and 20-foot long tube.^[9]

Launch systems

Each missile is stored and launched from a pressurized canister^[13] that protects it during transportation and storage and acts as a launch tube. These canisters were racked in Armored Box Launchers (ABL), which were installed on the re-activated Iowa class battleships USS Iowa, USS New Jersey, USS Missouri, and USS Wisconsin. The ABLs were also installed on eight Spruance class destroyers, the four Virginia class cruisers, and the USS Long Beach. These canisters are also in Vertical launching systems (VLS) in other surface ships, Capsule Launch Systems (CLS) in the later Los Angeles class submarines, and in submarines' torpedo tubes. All ABL equipped ships have been decommissioned.

For submarine-launched missiles (called UGM-109s), after being ejected by gas pressure (vertically via the VLS) or by water impulse (horizontally via the torpedo tube), the missile exits the water and a solid-fuel booster is ignited for the first few seconds of airborne flight until transition to cruise.

After achieving flight, the missile's wings are unfolded for lift, the airscoop is exposed and the turbofan engine is employed for cruise flight. Over water, the Tomahawk uses inertial guidance or GPS to follow a preset course; once over land, the missile's guidance system is aided by Terrain Contour Matching (TERCOM). Terminal guidance is provided by the Digital Scene Matching Area Correlation (DSMAC) system or GPS, producing a claimed Circular error probable of about 10 meters.

The Tomahawk Weapon System consists of the missile, Theater Mission Planning Center (TMPC)/Afloat Planning System, and either the Tomahawk Weapon Control System (on surface ships) or Combat Control System (for submarines).

Several versions of control systems have been used, including:

• v2 TWCS – Tomahawk Weapon Control System (1983), also known as "green screens," was based on an old tank computing system.
• v3 ATWCS – Advanced Tomahawk Weapon Control System (1994), first Commercial Off the Shelf, uses HP-UX.
• v4 TTWCS – Tactical Tomahawk Weapon Control System, (2003).
• v5 TTWCS – Next Generation Tactical Tomahawk Weapon Control System. (2006)

• 

  Launch of a Tactical Tomahawk cruise missile from the USS Stethem.

• 

  The USS Missouri launching a Tomahawk missile.

• 

  Submarine launch from USS Florida.

• 

  Launch trajectory from an Arleigh Burke class destroyer.

Navigation and other details

The TLAM-D contains 166 sub-munitions in 24 canisters; 22 canisters of seven each, and two canisters of six each to conform to the dimensions of the airframe. The sub-munitions are the same type of Combined Effects Munition bomblet used in large quantities by the U.S. Air Force with the CBU-87 Combined Effects Munition. The sub-munitions canisters are dispensed two at a time, one per side. The missile can perform up to five separate target segments which enables it to attack multiple targets. However, in order to achieve a sufficient density of coverage typically all 24 canisters are dispensed sequentially from back to front.

TERCOM – Terrain Contour Matching. A digital representation of an area of terrain is mapped based on digital terrain elevation data or stereo imagery. This map is then inserted into a TLAM mission which is then loaded on to the missile. When the missile is in flight it compares the stored map data with radar altimeter data collected as the missile overflies the map. Based on comparison results the missile's inertial navigation system is updated and the missile corrects its course. TERCOM was based on, and was a significant improvement on, "Fingerprint," a technology developed in 1964 for the SLAM.^[14]

On July 26, 2014 it was announced that 196 additional Block IV missiles had been purchased.^[15]

DSMAC – Digital Scene Matching Area Correlation. A digitized image of an area is mapped and then inserted into a TLAM mission. During the flight the missile will verify that the images that it has stored correlates with the image it sees below itself. Based on comparison results the missile's inertial navigation system is updated and the missile corrects its course.

• Total program cost: $US 11,210,000,000^[16]

Operators

Tomahawk operators

Remnants of a shot down Tomahawk from Operation Allied Force, showing the turbofan engine at the Museum of Aviation in Belgrade, Serbia.

United States Navy

• In the 1991 Gulf War, 288 Tomahawks were launched. The first salvo was fired by the cruiser USS San Jacinto on January 17, 1991. The attack submarines USS Pittsburgh and USS Louisville followed.
• On 26 June 1993, 23 Tomahawks were fired at the Iraqi Intelligence Service's command and control center.
• On 10 September 1995, the USS Normandy launched 13 Tomahawk missiles from the central Adriatic Sea against a key air defense radio relay tower in Bosnian Serb territory during Operation Deliberate Force.
• On 3 September 1996, 44 cruise missiles between UGM-109 and B-52 launched AGM-86s, were fired at air defence targets in Southern Iraq.
• On 20 August 1998, around 75 Tomahawk missiles were fired simultaneously to two separate target areas in Afghanistan and Sudan in retaliation to the bombings of American embassies by Al-Qaeda.
• On 16 December 1998, Tomahawk missiles were fired at key Iraqi targets in during Operation Desert Fox.
• In spring 1999, 218 Tomahawk missiles were fired by US ships and a British submarine during Operation Allied Force against key targets in Serbia and Montenegro.
• In October 2001, approximately 50 Tomahawk missiles struck targets in Afghanistan in the opening hours of Operation Enduring Freedom.
• During the 2003 invasion of Iraq, more than 802 tomahawk missiles were fired at key Iraqi targets.^[17]
• On 17 December 2009, two Tomahawk missiles were fired at targets in Yemen.^[18] One of the targets was hit by a TLAM-D missile. The target was described as an 'alleged Al-Qaeda training camp' in al-Ma’jalah in al-Mahfad a region of the Abyan governorate of Yemen. Amnesty International reported that 55 people were killed in the attack, including 41 civilians (21 children, 14 women, and six men). The US and Yemen governments refused to confirm or deny involvement, but diplomatic cables released as part of United States diplomatic cables leak later confirmed the missile was fired by a US Navy ship.^[19]
• On 19 March 2011, 124 Tomahawk missiles^[20] were fired by U.S. and British forces (112 US, 12 British)^[21] against at least 20 Libyan targets around Tripoli and Misrata.^[22] As of 22 March 2011, 159 UGM-109 were fired by US and UK ships against Libyan targets.^[23]
• On 23 September 2014, 47 Tomahawk missiles were fired by the United States from the USS Arleigh Burke and USS Phillipine Sea, which were operating from international waters in the Red Sea and Persian Gulf, against ISIL targets in Syria in the vicinity of Ar-Raqqah, Deir ez-Zor, Al-Hasakah and Al-Bukamal,^[24] and against Khorasan group targets in Syria west of Aleppo.^[25]
• The United States Navy has a stockpile of around 3,500 Tomahawk cruise missiles of all variants, with a combined worth of approximately US $2.6 billion.
• Tomahawk production for the United States Navy is scheduled to end in Fiscal Year 2015,^[26] with a replacement entering service a decade later.^[27]

Royal Navy

In 1995 the US agreed to sell 65 Tomahawks to the UK for torpedo-launch from her nuclear submarines. The first missiles were acquired and test-fired in November 1998; all Royal Navy fleet submarines are now Tomahawk capable, including the new Astute-class.^{[28][29][30][31]} The Kosovo War in 1999 saw the Swiftsure-class HMS Splendid become the first British submarine to fire the Tomahawk in combat. It has been reported that seventeen of the twenty Tomahawks fired by the British during that conflict hit their targets accurately; the UK subsequently bought 20 more Block III to replenish stocks.^[32] The Royal Navy has since fired Tomahawks during the 2000s Afghanistan War, in Operation Telic as the British contribution to the 2003 Iraq War, and during Operation Ellamy in Libya in 2011.

In April 2004, the UK and US governments reached an agreement for the British to buy 64 of the new generation of Tomahawk missile—the Block IV or TacTom missile.^[33] It entered service with the Royal Navy on 27 March 2008, three months ahead of schedule.^[34] In July 2014 the US approved the sale to the UK of a further 65 submarine-launched Block IV's at a cost of US$140m including spares and support;^[35] as of 2011 the Block III missiles were on Britain's books at £1.1m and the Block IV at £0.87m including VAT.^[36]

The Sylver Vertical Launching System on the new Type 45 destroyer is claimed by its manufacturers to have the capability to fire the Tomahawk, although the A50 launcher carried by Type 45 is too short for the weapon (the longer A70 silo would be required). Nevertheless, Type 45 has been designed with weight and space margin for a strike-length Mk41 or Sylver A70 silo to be retrofitted, allowing Type 45 to use TLAM Block IV if required, and the new Type 26 frigates will have strike-length VLS tubes. SYLVER user France is developing MdCN, a version of the Storm Shadow/Scalp cruise missile that has a shorter range but a higher speed than Tomahawk and can be launched from the SYLVER system.

United States Air Force

The USAF is a former operator of the nuclear-armed version of the Tomahawk, the BGM-109G Gryphon.

Other users

The Netherlands (2005) and Spain (2002 and 2005) were interested in acquiring the Tomahawk system, but the orders were later cancelled in 2007 and 2009 respectively.^[37][38]

In 2009 the Congressional Commission on the Strategic Posture of the United States stated that Japan would be concerned if the TLAM-N were retired, but the government of Japan has denied that it had expressed any such view.^[39]

It is believed that the SLCM version of the Popeye was developed by Israel after the US Clinton administration refused an Israeli request in 2000 to purchase Tomahawk SLCM's because of international MTCR proliferation rules.^[40]

As of March 12, 2015 Poland has expressed interest in purchasing long-range Tomahawk missiles for its future submarines.^[41]

Replacement

As of 2014, the U.S. Navy is seeking a replacement for the Tomahawk, the Next-Generation Land Attack Weapon, which shall have increased lethality and survivability; options include Tomahawk improvements or a new weapon. The Navy is developing a surface-launched version of the air-launched Long Range Anti-Ship Missile, aiming to defeat enemy air defenses using sensors and autonomous flight. A future version of the LRASM may include several vendors, but Lockheed Martin has been the principal developer and is investing funds to develop and test an LRASM that can be launched from vertical launch systems on Navy ships.^[42] The Navy believes its inventory of 4,000 Tomahawk missiles are sufficient for future scenarios, so production is planned to end after 2016, relying on stocks until the next-generation land-attack weapon is developed; Raytheon opposes this action, claiming that Tomahawk production takes over 100 suppliers in 24 US states, and that restarting production could take two years and increase costs. It could take up to a decade for a replacement to be fielded, during which time Tomahawk stocks may potentially be depleted.^[43] The Navy's FY 2016 budget supports a new Next Generation Strike Capability (NGSC) effort, which combines the Next-Generation Land Attack Weapon with the Offensive Anti-Surface Warfare (OASuW) Increment II effort to procure a new anti-ship missile. NGSC could either be a common weapon or a family of weapons, but the goal is to use technologies "across multiple mission areas."^[44]

See also

• List of missiles
  • RK-55
  • 3M-54 Klub
  • Raduga Kh-55
  • Nirbhay
  • AGM-129 ACM
  • Hyunmoo-3
  • DH-10
  • Babur (cruise missile)
• UGM-89 Perseus
• ArcLight (missile)
• Scalp Naval (missile)

References

External links

Wikimedia Commons has media related to BGM-109 Tomahawk.

• Raytheon Official site for the Tomahawk missile