Up to 130 Tomahawk cruise missiles are reported to have been fired in three days of the current Operation Odyssey Dawn against integrated air defense targets in Lybia. We’re analyzing the evolution in capabilities of a system that gained notoriety 20 years ago during Operation Desert Storm.
The Tomahawk Land Attack Cruise Missile (TLAM) is a tactical cruise missile that can be launched from a surface ship or a submarine. It is designated RGM-109 when launched from a surface ship and UGM-109 for submarine version. Tomahawks offer long range precision navigation capabilities and high targeting accuracy. With its relatively small size and low sea-skimming flight altitude, a Tomahawk typically takes full advantage of the earth curvature to stay out of range of ground and ship-based radars. The ‘stealth’ feature, augmented by a low subsonic speed present a challenge for air defense systems. Thus presenting a decisive solution for strike planners dealing with a wide variety of strike scenario. The system is primarily used to neutralize high value strategic targets during a full aerial offensive campaign such as key command, control and communications facilities. Its ability to deliver bomblets sub munitions against area targets (such as deployed ground troops, soft skins vehicles convoys, artillery staging area etc) can induce intimidated enemy commanders into operational paralysis. It is also a politically viable air-delivered precision weapon that doesn’t require putting an aviator’s life at risk. Its high level of accuracy and precision also diminish the risks associated with unintended damages. Foremost it offers the ability to fight entire campaigns ‘remotely via ships or submarines’.
The TLAM that are being employed in the current Operation Odyssey Dawn campaign against Colonel Qaddafi forces are either TLAM-C, with the -C indicating they carry WDU-25/B high explosive blast fragmentation warheads or TLAM-D armed with BLU-97/B Combined Effect Bomblets. The bomblets disperse 166 exploding sub munitions against area targets. The Lybian integrated air defense network which is said to be saturated with surface to air missiles systems relics of the former Soviet Union SA-2, SA-3 and SA-5. Reports of B-2 bombers, F-15 and F-16 fighter jets and EA-18G electronic warfare aircraft in addition to French Mirage 2000-D seen overflying Lybian towns on Sunday suggests a decreased activity (or their being switched off) of the integrated air defense network.
TLAMs are launched from submarines or surface ships by solid propellant rocket booster motor. The rocket booster motor delivers 600 lbs of thrust and uses thrust vectoring in order to provide missile direction for for the 12 seconds period of its firing, subsequent to which it is jettisoned. Propulsion for the remaining portion of the flight is assumed by a low bypass small turbofan engine (600-700 lbs thrust); the Williams International F415-WR-400/402 which has recently replaced the F107-WR-402. During cruise ,missile flight control and stability are maintained by a pair of wings along with four tail fins that are automatically deployed from a recessed position within the missile. A ventral air intake is also deployed in order to maintain air flow to the turbojet engine.
Current production Block IV models have provided significantly improved tactical capabilities than earlier Block I, II and III versions. The Block I TALM-C were first deployed in March 1983 and are sometimes referred to as Tactical Anti Shipping Missile (TASM) systems. Because they are primarily designed for the anti-shipping role, they employ an AN/DSQ-28 active radar seeker that operates in the J-band of the electromagnetic spectrum. This system is also found on A/R/UGM-84 Harpoon Anti Ship Missile targeting system.
Since the appearance of the Block II Tomahawk, the highly promising TERCOM navigation system has been at the heart of the missile high level of accuracy. While accurate navigation over the water can be entrusted to an Inertial Navigation System, the remaining overland portion of flight en route to a target can be challenging. For that reason a two tier Inertial Navigation System plus terrain-following radar has been established. The combination of INS and TERCOM (Terrain Contour Matching) requirements have been implemented in the McDonnell-Douglas AN/DPW-23 mid course guidance system. This system gives the missile advanced navigation capabilities while flying over the sea and overland. The TERCOM terrain recognition technology maintains a database of reference maps compiled by National Geo-spatial Intelligence Agency (formerly NIMA, National Imagery and Mapping Agency). These maps are constantly referenced by the TERCOM system during the missile flight in order to maintain the missile in its previously programmed course.
Block II Tomahawks whose deliveries began in 1986 with the INS (Inertial Navigation System) and TERCOM mid-course guidance system additionally received a new terminal phase guidance and targeting system in the form of DSMAC (Digital Scenery Matching Correlation) AN/DXQ-1 system. This system integrates an electro-optical sensor to a image correlation engine. A database of target images is fed to the correlation engine in order to identify (recognize) potential targets encountered during flight and captured by the optical sensor. The AN/DXQ-1 gave the missile added tactical flexibility by allowing it to attack targets in 3 different ways: a straight attack from the side of a target, a programmable pop-up/terminal dive into the target and a Programmed War head Detonation (PWD) that commands the warhead to explode when the missile is overflying a given target area. Together with the TAINS (TERCOM plus INS), the DSMAC gave the Tomahawk Block II an estimated accuracy of between 10 and 30 meters. Both WDU-25/B and BLU-97/B (from 1988) warheads could be used (TALM-C and TALM-D respectively). The Block II have helped cement Tomahawk’s operational reputation most visibly during Operation Desert Storm in Iraqi. In 1991, against Saddam Hussein fielded forces of up to 1,000,000 troops, 282 Tomahawks were successfully launched out of a total of 297 fired.
By May of 1993 the Block II was ready to receive its latest upgrades. A jam-resistant GPS (Global Positioning System) came to complement the TAINS and DSMAC guidance system. Allowing the missile to survive in environment where hostile ‘electronic warfare’ jamming signals are broadcast became a requirement. A smaller and lighter WDU-36/B explosive blast fragmentation warhead was mated to the missile further improving its range. The block III procurement system simple as Block II missiles would undergo the upgrade during maintenance. Both systems are currently still in US Navy inventory until residual Block II inventory is upgraded. Funding for Block III Tomahawk is ongoing until planned expiration date of fiscal year 2020.
The Block IV Tactical Tomahawk (TacTom) reached Initial operational Capabilities in May 2004. It incorporates the latest achievements in network-centric warfare capabilities and resulting tactical benefits. Network centric warfare systems can share tactical data via a wide variety of communications technologies and links in real or near real time. This approach allows weapon system to support each other in a mutually coordinated way. War fighters have a full picture of the battle field and can manage their resources efficiently and with increased lethality thus improving the likelihood of a successful outcome during engagement and even entire campaign.
The Block IV uses three steerable tail fins (instead of four), two deployed wings, an improved 1,000 miles (1,605 km) range and has a small fixed ventral intake vent opening that breathes air to a smaller and lighter Williams International F415-WR-400/402 low bypass turbojet engine. The rocket booster motor has been incorporated to the missile assembly preventing it from being launched from a submarine torpedo as it has been possible on previous versions. Now the missile submarine launch can only be conducted with the missile still stored in its original capsule storage container; this forms the basis for the Mk 43 CCLS (Composite Capsule Launch System). Launches from surface ships require the missile in its MK 41 canister (missile container) to be mated to a Mk14 ship’s Vertical Launch System (VLS) prior to firing. As a result Block IV Tomahawk are normally procured as All Up Round (AUR); still sealed in their original delivery canisters or capsules containers. . (see recent February 16th 2011 $23,317,060 contract award to Raytheon for procurement of 64 Fiscal Year 2011 Tomahawk Composite Capsule Launching System (CCLS) Capsules, December 16th 2010 $209,027,172 award contract to Raytheon for procurement of 196 fiscal 2011 Tomahawk Block IV all up round missiles via modification and additional procurement of 132 VLS and 64 CLS missiles and also December 13th 2010 Raytheon award of $33,499,596 contract for full recertification of 148 All-Up-Round (AUR) Tomahawk missiles and fixed support for encanisterization/decanisterization of MK-14 AUR missiles). This simplified AUR approach provides logistic gains in the overall procurement/supply chain. With the cheaper F415 turbojet and the fact that Block IV are sourced from re-manufactured Block I TASM, the Block IV Tomahawk encompasses cost savings of the order of 50% in procurement price compared to Block II and III.
The most dramatic improvements to the missile are in tactical flexibility. The introduction of a UHF Satcom data link allows for in-flight target updates ,real time targeting, in-flight redirection, planned time of arrival on target, on-board TV camera for real time image transmitting, and the pre programming of up to 15 alternate targets to which the missile can be re-directed to while in flight. These advanced capabilities can be fully exploited by strike planners using network centric advanced integrated Tomahawk Fire Control Systems FCS (Fire Control Systems). The AN/SWG-3 Tomahawk Weapon Control System (TWCS) are installed on board surface ships. Submarines Combat Control Systems are open architecture integrated battle management and control station that can interface to all the weapons systems including the Tomahawk. Raytheon AN/BYG-1(V) Combat Control System (CCS) for submarines is the currently produced version. (see June 24th 2010 contract award to Lockheed Martin, Information Systems and Global Services, King of Prussia, Pa., of $16,575,612 for the maintenance, upgrade and development of Tactical Tomahawk Weapons Control System software for US Navy and UK Government under the Foreign Military Sales program).
With the significantly high number of inventory TASM or Block I Tomahawk that seems to have been retained throughout the years (up to 1,253 units probably) the Block IV is ensured of a steady supply of new All Up Round.