The Tomahawk Land Attack Missile is a long-range, all-weather, subsonic cruise missile that
is primarily used by the United States Navy and Royal Navy in ship and submarine-based
land-attack operations.
Introduced by General Dynamics in the 1970s, it was initially designed as a medium to long-range,
low-altitude missile that could be launched from a surface platform.
Since then, it has been upgraded several times with guidance systems for precision navigation.
It is now manufactured by Raytheon.
In 2016, the U.S. Department of Defense purchased 149 Tomahawk Block IV missiles for $202.3
million.
The missile is named after the tomahawk, a one-handed axe used by the Native Americans.
Variants:
There have been several variants of the BGM-109 Tomahawk employing various types of warheads:
BGM-109A Tomahawk Land Attack Missile – Nuclear (TLAM-N) with a W80 thermonuclear weapon.
Retired from service sometime between 2010 and 2013.
RGM/UGM-109B Tomahawk Anti Ship Missile (TAS-M) – 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variant; withdrawn from service in the 1990s.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BGM-109G Ground Launched Cruise Missile (GLCM) – with a W84 nuclear warhead; withdrawn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 1991.
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).
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Launch systems:
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.
Terminal guidance is provided by the Digital Scene Matching Area Correlation system or
GPS, producing a claimed circular error probable of about 10 meters.
Navigation:
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 onto 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.
On July 26, 2014 it was announced that 196 additional Block IV missiles had been purchased.
Specifications:
Weight: 1,300 kg, 1,600 kg with booster
Length: Without booster: 5.56 m
With booster: 6.25 m
Diameter: 0.52 m
Detonation Mechanism: FMU-148 since TLAM Block III, others for special
applications
Engine: Williams International F107-WR-402 turbofan
using TH-dimer fuel and a solid-fuel rocket booster
Wingspan: 2.67 m
Operational Range: Block II TLAM-A – 2,500 km
Block III TLAM-C, Block IV TLAM-E – 1,700 km
Flight altitude: 30–50 m AGL
Speed: Subsonic; about 890 km/h
Guidance System: GPS, INS, TERCOM, DSMAC, active radar homing
Launch Platform: Vertical Launch System and horizontal submarine
torpedo tubes
Unit cost: $1.87M (Block IV)