Mk 153 Shoulder-Launched Multipurpose Assault Weapon

Mk 153 Shoulder-Launched Multipurpose Assault Weapon
Mk 153 Shoulder-Launched Multipurpose Assault Weapon
	Mk 153 SMAW and munition casing.
Type	Multi-role (anti-fortification, anti-armor) rocket launcher
Place of origin	United States
Service history
In service	1984–present
Used by	See Operators
Wars	Operation Just Cause; Gulf War; War in Afghanistan; Iraq War; Yemeni Civil War Saudi Arabian-led intervention in Yemen; Saudi Arabian–Yemeni border conflict;
Production history
Designer	McDonnell Douglas
Manufacturer	Nammo Talley (formerly Talley Defense Systems)
Unit cost	US$13,000
Variants	M141 Bunker Defeat Munition
Specifications
Mass	7.54 kg (16.6 lb) (empty); 13.39 kg (29.5 lb) (loaded)
Length	760 mm (30 in) (unloaded); 1,371 mm (54.0 in) (loaded)
Crew	2 (can be operated by one person, but at lower rate of fire)
Cartridge weight	4.5 kg (9.9 lb) (HEAA); 4.2 kg (9.3 lb) (HEDP)
Caliber	83.5 mm (3.29 in) (bore diameter); 83.0 mm (3.27 in) (rocket diameter)
Rate of fire	3 rounds per minute (practical)
Muzzle velocity	220 m/s (720 ft/s)
Effective firing range	250 m (820 ft) (HEDP); 500 m (1,600 ft) (HEAA)
Maximum firing range	1,800 m (5,900 ft)
Feed system	Detachable single-rocket casing
Sights	Iron sights (250 m, 820 ft); Mk 42 Day Sight (3.8× magnification telescopic sight); Night vision sight

The Mk 153 Shoulder-Launched Multipurpose Assault Weapon (SMAW) is a shoulder-launched rocket weapon with the primary function of being a portable assault weapon (i.e. bunker buster) and a secondary anti-armor rocket launcher. Developed from the B-300, it was introduced to the United States Armed Forces in 1984. It has a maximum effective range of 500 metres (550 yd) against a tank-sized target.

It can be used to destroy bunkers and other fortifications during assault operations; it can also destroy other designated targets using the dual mode rocket, and main battle tanks using the high-explosive anti-tank rocket. Operations in Afghanistan and Iraq saw a thermobaric rocket added (described as a "Novel Explosive" (NE)), which is capable of collapsing a building.^[2]

Service history[]

The SMAW system (launcher, ammunition and logistics support) was fielded in 1984 as a United States Marine Corps–unique system. The Mod 0 demonstrated several shortcomings, resulting in a series of modifications in the mid-2000s. These modifications included a re-sleeving process for bubbled launch tubes, rewriting/drafting operator and technical manuals, and a kit to reduce environmental intrusion into the trigger mechanism. This also includes an optical sight modification to allow the high-explosive anti-armor (HEAA) rocket to be used effectively against moving armor targets. The U.S. Armed Forces fielded boresight bracket kits which correct the loss of accurate boresight issues between the launch tube and spotting rifle. During Operation Desert Storm, 150 launchers and 5,000 rockets were deployed by the United States Army. Initially the Army showed interest in the system but ultimately returned the launchers and any unused rockets to the Marine Corps. Later, the U.S. Army developed the SMAW-D ("Disposable"), designated by the Army as the M141 Bunker Defeat Munition.

Follow-On To SMAW[]

In 2002, the Corps began a program to develop a successor to the SMAW system, tentatively titled "Follow-On To SMAW".^[3] The contract was awarded to Lockheed Martin and Israel Military Industries (IMI);^[4] this resulted in the enhanced FGM-172 SRAW. In combat operations, it was ultimately used to augment, rather than replace, the SMAW system.

SMAW II program[]

In 2008, a replacement program was again initiated and titled the SMAW II.^[5] It was developed in tandem with a round capable of being fired from an enclosed area without ill effects on the environment and personnel. Its combined weight is 13.5 kilograms (29.7 lb)—5.3 kg (11.7 lb) for the launcher, 8.2 kg (18 lb) for the rocket. The contract was worth up to US$51.7 million^[5]

SMAW II Serpent[]

Nammo Tally displaying the Serpent at Modern Day Marine 2010

In 2012, Raytheon Missile Systems developed a SMAW II launcher called "Serpent", and Nammo Talley developed new rounds for the Serpent. The Serpent is similar in many respects to the first SMAW launcher, except that it replaces the standard SMAW launcher's spotting gun with sophisticated fire control electronics. The sighting unit on the launcher is enclosed in a unique roll-cage to protect it. The roll-cage also serves as a carry handle. The development reduced the over-all weight by four and a half pounds (2.0 kg) from the older SMAW launcher. The Serpent fires the same rounds as the standard SMAW and supports new and improved/enhanced rounds.^[6]^[7]

Design[]

Compared to the Israel Military Industries' B-300 weapon that it was developed from, the SMAW has slower projectile velocities, it and its ammunition are both heavier, and it takes a second crew member to keep up with the B-300's rate-of-fire, but some of its projectile options have longer ranges than the B-300. The Mk 153 SMAW has an 83.5 millimetres (3.29 in) diameter tube and fires 83-millimetre (3.3 in) rockets. It is a man-portable weapon system consisting of the Mk 153 launcher, the Mk 3 Mod 0 Encased High-Explosive, Dual-Purpose (HEDP) rocket, the Mk 6 Mod 0 Encased High-Explosive, Anti-Armor (HEAA) Rocket, the Mk 7 Mod 0 Common Encased Practice Rocket, the Mk 80 Mod 0 Encased Novel Explosive (NE) rocket, and the Mk 217 Mod 0 spotting rifle cartridge.

The launcher consists of the launch tube, spotting rifle, electro-mechanical firing mechanism, mounting brackets, open battle sights and a mount for the Mk 42 Mod 0 day sight or AN/PVS-4 or AN/PVS-17B night sights. The launch tube is made of fiberglass-epoxy composite material with a gelcoat on the bore. The spotting rifle is mounted on the right side of the launch tube. It functions semi-automatically by primer actuation, meaning that when fired the primer sets back and unlocks the breech of the spotting rifle, ejecting the spent round. The firing mechanism mechanically fires the spotting rifle and uses a magnet to fire the rocket. The mounting brackets connect the components and provide the means for boresighting the weapon, while the encased rockets are loaded at the rear of the launcher. The spotting cartridges are stored in a magazine in the cap of the encased rocket.

The 9×51mm Mk 217 spotting round is ballistically matched to the rocket and serves to increase the gunner's first-round hit probability. Each round consists of a special 9 mm projectile which contains a tracer compound, crimped into a 7.62×51mm NATO casing with a .22 Hornet primer.^[8] The system can be used in conjunction with the AN/PEQ-2 aiming light in place of the spotting rifle.

As with all of these types of recoilless rocket weapons, the backblast that is created when it is fired is a primary safety concern. When the rocket is fired, the rocket propellant is expended entirely within the rocket encasement. This is the cause of the extremely loud and violent backblast. This backblast extends in a 90-meter, 60° cone to the rear of the weapon. The backblast is lethal out to 30 metres (98 ft) and still extremely dangerous to 90 metres (300 ft). An assistant gunner is often used during employment of the weapon system to monitor the backblast area and clear it of fellow troops, or to notify the gunner of obstructions that could reflect the force of the backblast back at the gun team. The gunner is only cleared to launch a rocket when he hears the command "Backblast area secure" from his assistant gunner. Rounds are under development that would enable a user to fire the rocket from an enclosed building without risk of injury.^[9]

The Mk 153 Mod 2 is an enhanced variant, featuring an electronic modular ballistic sight (MBS) in place of the 9 mm spotting system. The MBS has a laser rangefinder and thermal weapon sight to provide a firing solution using a displaced reticle, where crosshairs are adjusted for distance and environmental factors; it is lighter, more reliable, and can be detached from the launcher. While the Mod 0 weighs 7.5 kg (16.5 lb), the Mod 2 weighs 5.9 kg (13 lb) with the MBS attached, and 3.9 kg (8.5 lb) with the MBS detached. Other improvements include increased pad size on the forward grip and foldable backup iron sights.^[10] The Mod 2 systems were expected to replace the existing inventory by October 2020.^[11]^[12]^[13]

View showing sight
Two SMAW teams
A training round is fired

Rockets[]

The Mk 4 Mod 0 Encased High-Explosive, Anti-Armor, Practice Rocket is used in training. The warhead consists of a blue plastic projectile attached to a rocket motor similar to the HEDP rocket. The rocket has no explosive capability against the target except for kinetic energy. Upon impact against a target, the plastic warhead ruptures, dispensing an inert white spotting powder.

The Mk 3 Mod 0 Encased High-Explosive, Dual Purpose (HEDP) rocket is effective against bunkers, masonry and concrete walls and light armor. Initiated by a crush switch in its nose, the HEDP rocket is able to distinguish between hard and soft targets resulting in greater penetration into soft targets for increased damage potential. The HEDP round is capable of penetrating 20 centimetres (7.9 in) of concrete, 30 centimetres (12 in) of brick or up to 210 centimetres (6.9 ft) of wood-reinforced sandbags.

The Mk 6 Mod 0 Encased High-Explosive, Anti-Armor (HEAA) rocket is effective against current tanks without additional armor and utilizes a standoff rod on the detonator, allowing the explosive force to be focused on a small point and for maximum damage against armored targets. The HEAA round is capable of penetrating up to the equivalent of 600 mm of rolled homogeneous steel.

The Mk 80 Mod 0 Encased Novel Explosive (SMAW-NE) rocket is effective against caves and bunkers. The SMAW-NE has a 4 lb (1.8 kg) charge of PBXIH-135,^[14] an enhanced-blast warhead. The Indian Head Naval Surface Warfare Center teamed with Marine Corps Systems Command and Talley Defense Systems to respond to an urgent U.S. Marine Corps need for a shoulder-launched enhanced-blast warhead in 2003. It was used in combat during both the First and Second offensives in Fallujah, in 2004.