Stryker - Stryker Vehicle

The IAV (Interim Armored Vehicle) Stryker is a family of eight-wheeled, armored fighting vehicles derived from the Canadian LAV III and based on the Swiss Piranha III 8×8. Stryker vehicles are produced by General Dynamics Land Systems for the United States Army. It has 4-wheel drive (8×4) and can be switched to all-wheel drive (8×8).

The vehicle is named for two American servicemen who posthumously received the Medal of Honor: Private First Class Stuart S. Stryker, who died in World War II, and Specialist Four Robert F. Stryker, who died in the Vietnam War (no relation).

Development history

Background

In October 1999, General Eric Shinseki, then U.S. Army Chief of Staff, outlined a transformation plan for the army that would allow it to adapt to post-Cold War conditions. The plan, named "Objective Force", would have the army adopt a flexible doctrine that would allow it to deploy quickly, and equipped for a variety of operations. An early phase of the plan called for the introduction of an 'Interim Armored Vehicle' which was intended to fill the capability gap between heavy and lethal, but not easily deployable vehicles (such as the M2 Bradley), and easily deployed, but lightly armed and protected vehicles (such as the Humvee). A variant of the Canadian LAV III offered by the General Dynamics-General Motors Defence Canada team was ultimately awarded the contract in November 2000 to produce 2,131 Stryker vehicles of all variants for equipping six rapid deployment Brigade Combat Teams. On 27 February 2002, the Army formally renamed the Interim Armored Vehicle as the Stryker. It w as called the "Interim" Armored Vehicle because it was initially supposed to be a temporary measure until light air-mobile vehicles from the Future Combat Systems program came online, none of which did before FCS was canceled.

Production

The Stryker 105mm M1128 Mobile Gun System (MGS) moved into low-rate initial production in 2005 for evaluation, and entered full production in 2007. General Dynamics Land Systems-Canada assembles the Stryker for the U.S. Army in a plant in London, Ontario.

The vehicle is employed in Stryker Brigade Combat Teams, light and mobile units based on the Brigade Combat Team Doctrine that relies on vehicles connected by military C⁴I (Command, Control, Communications, Computers, and Intelligence) networks.

The Stryker has come under intense scrutiny from military experts since its introduction in the US Army; this has also been the subject of mass media coverage.

General Dynamics's Robotic Systems division was developing autonomous navigation for the Stryker and several other vehicles with a $237 million contract until the program was cut in July 2011. Tank Automotive Research, Development and Engineering Center (TARDEC) has also tested an active magneto rheological suspension, developed by MillenWorks for the Stryker, at the Yuma Proving Ground, which resulted in greater vehicle stability.

Upgrades

More than 1,000 Stryker vehicles have been rebuilt by Anniston Army Depot and returned to operations.

The US Army plans to improve its fleet of Stryker vehicles with the introduction of improved semi-active suspension, modifications reshaping the hull into a shallow V-shaped structure, to protect against improvised explosive devices (IEDs). Also included are additional armor for the sides, redesigned hatches to minimize gaps in the armor, blast absorbing mine resistant seating, non-flammable tires, an upgrade to the remote weapon station that allows it to fire on the go, increased 500 amp power generation, a new solid state power distribution system and data bus, and the automotive and power plant systems improvements to support a 25 percent Gross Vehicle Weight increase. The upgraded V-hull will be part of the new StrykShield situational awareness kit, which will address many of these upgrades. Allegheny Technologies' ATI 500-MIL armor steel was designated the primary armored plating for the StrykShield package in 2008.

The upgrade incorporating lessons learned from combat in Afghanistan is designated LAV-H and General Dynamics had a technology demonstrator displayed at the 2007 Association of the United States Army (AUSA) Exposition. In March 2010, it was reported that General Dynamics and Army were working to incorporate a double V-hull into the Stryker design. In July 2010 the Army awarded a $30 million contract to GDLS to start production of the new hull.

On 9 March 2011, the Department of Defense's director of operational test and evaluations testified that the new V-hull design was "not suitable" for long missions in Afghanistan's terrain. The issues are due to the tight driver's compartment and difficulty releasing the seat to extract an incapacitated driver. General Dynamics stated these issues would be corrected before the new Stryker version deploys. The upgrade also adds significant weight to the vehicle, which can cause it to sink into soft ground.

In July 2011, 450 Double V-Hull (DVH) variants of the Stryker vehicle were ordered; the total was increased to 742 a few months later and then to 760 in 2012. DVH Strykers include a new hull configuration, increased armor, upgraded suspension and braking systems, wider tires, blast-attenuating seats, and a height management system.

By August 2012, the Army's Stryker fleet included over 4,187 vehicles, with 10 flat-bottom variants and 7 in double V-hull designs. In Afghanistan, it retained a 96 percent readiness rate. To upgrade the existing fleet, the Army has implemented an Engineering Change Proposal (ECP) program to provide a stronger engine, improved suspension, more on-board electrical power, and next-generation networking and computing technology. Phase 1 of the ECP includes an electrical power upgrade by replacing the current 570 amp alternator with a higher current 910 amp alternator, replacing the existing 350 horsepower engine with a 450-horsepower engine, a stronger suspension system to improve mobility at higher weights, and an in-vehicle network to improve data and video sharing between crew stations and more secure and reliable data sharing between vehicle systems. On 28 May 2013, Kongsberg Integrated Tactical Systems was awarded a contract to supply the Driver's Situational Awareness Display (DSAD) and Commander's Situational Awareness Display (CSAD) for the Stryker ECP program, featuring an on-board processor and additional I/O ports for both data and video.

As of January 2014, the U.S. Army had two Stryker Brigades that completed the DVH upgrade with a third brigade, the 2nd Brigade, 2nd Infantry Division at Joint Base Lewis-McChord, to be fully upgraded by the end of FY 2016. In mid-October 2014, the Army approved the procurement of DVH Strykers for a fourth Stryker brigade, with conversions to 360 vehicles to begin in FY 2017. The Strykers will also be the first to receive ECPs to handle the upgrades better than the previous three brigade vehicles, which increased weight, decreased mobility, and added a power burden; previous DVH-upgraded Strykers will get ECP enhancements when funding is available. ECP enhancements include a more robust 450 HP engine, a more powerful 910 amp power generator, a chassis upgrade to handle the new engine, and improvements to the vehicle's internal network. Upgrading the fourth brigade also kept the production line active through 2018, whereas deciding to upgrade after the line had cl osed would be more difficult and costly from reopening it. The Army plans to increase the lethality of Stryker ICVs by having half equipped with a 30 mm cannon and the other half given a Javelin anti-tank missile on the existing RWS in each brigade.

Design

The Stryker is based on the LAV III light-armored vehicle, which in turn was based on the Swiss MOWAG Piranha III 8x8.

The vehicle comes in several variants with a common engine, transmission, hydraulics, wheels, tires, differentials and transfer case. The M1130 Command Vehicle and M1133 Medical Evacuation Vehicle have an air conditioning unit mounted on the back. The medical vehicle also has a higher-capacity generator. A recent upgrade program provided a field retrofit kit to add air conditioning units to all variants, and production started in 2005 on the Mobile Gun System mounting an overhead GDLS 105 mm automatic gun.

Engine and mechanical features

For its powerpack the Stryker uses a Caterpillar diesel engine common in U.S. Army medium-lift trucks, eliminating additional training for maintenance crews and allowing the use of common parts. Because of obsolescence concerns, the Caterpillar 3126 engine was recently replaced by a Caterpillar C7 engine and the Allison 3200SP transmission.

Pneumatic or hydraulic systems drive almost all of the vehicle's mechanical features; for example, a pneumatic system switches between 8x4 and 8x8 drive.

Designers strove to ease the maintainer's job, equipping most cables, hoses, and mechanical systems with quick-disconnecting mechanisms. The engine and transmission can be removed and reinstalled in approximately two hours, allowing repairs to the turbocharger and many other components to be done outside the vehicle.

Command, control, and targeting

Extensive computer support helps soldiers fight the enemy while reducing friendly fire incidents. Each vehicle can track friendly vehicles in the field as well as detected enemies. The driver and the vehicle commander (who also serves as the gunner) have periscopes that allow them to see outside the vehicle without exposing themselves to outside dangers. The vehicle commander also has access to a day-night thermal imaging camera which allows the vehicle commander to see what the driver sees. The vehicle commander has almost a 360-degree field of vision; the driver, a little more than 90 degrees.

Soldiers can practice training with the vehicles from computer training modules inside the vehicle.

General Dynamics Land Systems is developing a new Power and Data Management Architecture to handle computer upgrades.

The Stryker's thermal sights can see out to 7,800 ft (2,400 m; 1.48 mi), compared to 330 ft (100 m) for night vision sights used by dismounted soldiers. This capability allows the vehicle to warn dismounted soldiers of threats which lie beyond the range of their night vision sights.

Protection

The Stryker's hull is constructed from high-hardness steel which offers a basic level of protection against 14.5 mm rounds on the frontal arc, and all-around protection against 7.62 mm ball ammunition. In addition to this, Strykers are also equipped with bolt-on ceramic armor which offers all-around protection against 14.5 mm, armor-piercing ammunition, and artillery fragments from 155 mm rounds. Problems were encountered with the initial batch of ceramic armor when it was found that a number of panels failed in tests against 14.5 mm ammunition. Army officials determined that this was due to changes in the composition and size of the panels introduced by their manufacturer, IBD Deisenroth. A stopgap solution of adding another 3 mm of steel armor was introduced until a permanent solution could be found. The issue was eventually resolved later in 2003 when DEW Engineering was selected as the new, exclusive supplier for the ceramic armor.

In addition to the integral ceramic armor, optional packages have been developed. These include slat armor and Stryker reactive armor tiles (SRAT) for protection against rocket propelled grenades and other projectiles, the hull protection kit (HPK), armored skirts for additional protection against improvised explosive devices, and a ballistic shield to protect the commander's hatch.

The Army began sending reactive armor tiles to Strykers in Iraq in 2004, as well as tiles for Abrams tanks and Bradley Fighting Vehicles. Tiles have to be specifically crafted for each vehicle type they are fitted to. Insurgents attempted to counter reactive armor by having teams fire multiple RPGs at once, but at close range these groups could be engaged and broken up. Reactive armor can be defeated by tandem-charge weapons like the RPG-29 or by explosively formed penetrators, although the Bradley's tiles can withstand EFPs. In May 2009, General Dynamics and Rafael won a contract to provide SRAT tiles to replace slat armor on Strykers. The additional weight of the two systems is comparable, but reactive armor tiles offer greater vehicle stability and maneuverability and "assured" rather than "statistical" protection.

The Stryker also incorporates an automatic fire-extinguishing system with sensors in the engine and troop compartments that activate one or more halon fire bottles, which can also be activated by the driver, externally mounted fuel tanks, and a CBRN (Chemical, Biological, Radiological, Nuclear) Warfare system which will keep the crew compartment airtight and positively pressurized.

Reports from military personnel and analysts state that the Stryker is superior to other light military vehicles regarding survivability against IEDs (improvised explosive devices).

Armament

With the exception of some specialized variants, the primary armament of the Stryker is a Protector M151 Remote Weapon Station with .50-cal M2 machine gun, 7.62 mm M240 machine gun, or Mk 19 automatic grenade launcher. The choice of armament was driven by many factors. The US Army wanted a vehicle that could rapidly transport and protect infantry to and around battlefields.

30 mm cannon

While the Stryker MGS gives light brigades heavy firepower, the baseline infantry carrier vehicle has a light armament. Stryker program officials are working to mount a 30 mm cannon to the ICV's remote weapons station. With the number of MGS vehicles per brigade being reduced, individual ICVs are to be up-gunned. The cannon would give greater firepower without needing to add a turret. The plan is to purchase and test a company set of 30 mm cannons and also determine if they should be issued for every Stryker or have one per company. The Army planned to test stabilized 30 mm cannons in early 2014, including Kongsberg Protech Systems' Medium Caliber Remote Weapons Station. Kongsberg (which makes the M151 RWS on the Stryker) joined with General Dynamics (which makes the Stryker) for the MCRWS in 2008. The MCRWS is not a true turret, which would extend into the crew compartment and take up space. It can be loaded from inside the vehicle, but does eliminate one of the four roof hatc hes. The autocannon is dual-fed from two ammunition boxes, each containing 150 30 mm rounds for armor piercing or anti-personnel duties, and it has a 7.62 mm coaxial machine gun.

Test firings of a 30 mm cannon in the Kongsberg MCRWS occurred on a Stryker demonstrator vehicle on 19 February 2014. The cannon showed increased lethality and accuracy over the standard .50-caliber machine gun at ranges from 600â€"1,550 meters, with four rounds from five-round bursts hitting the targets. Up-gunning Stryker vehicles is expected to give infantrymen greater fire superiority to end firefights quicker. The 30 mm cannon is capable of hitting targets at a range of over 2,000 meters (1.2 mi). Army leaders were impressed with the demonstration and are looking to advance the proposal and add the system onto vehicles in service.

After comparative testing of the Kongsberg MCRWS mounted to Stryker vehicles, the U.S. Army approved on 22 April 2015 the equipping of 81 of the 2nd Cavalry Regiment's Stykers with 30 mm cannons after the unit requested the upgrade. The cannons are meant to increase the ICV's lethality against other light armor vehicles while preserving its wheeled mobility advantages. Reviews of the effectiveness of these new turrets in Stryker companies will inform decisions regarding the upgrade of more Strykers across the nine Stryker Brigades. The remote turret requires a modification of the hull roof, and adds an additional two tons of weight that may lead to upgrading the suspension. Outfitting the first Strykers with Mk44 Bushmaster II cannons is planned to occur in the next two years. The cannon will be able to fire airburst rounds that explode above a target to hit people hiding behind walls and can enable it to shoot down unmanned aerial vehicles. The Kongsberg turret and Orbital ATK X M813 variant of the Mk44 Bushmaster were officially selected in December 2015. The first upgraded Stryker, designated XM1296 "Dragoon", was delivered for testing on 27 October 2016, with fielding to begin in May 2018.

Mobility

Strategic and operational

One of the key objectives outlined as part of the army transformation plan was the ability to deploy a brigade anywhere in the world within 96 hours, a division in 120 hours, and five divisions within 30 days. Operational mobility requirements dictated that the vehicle be transportable by C-130 aircraft and that it would be able to roll-off manned and ready to fight.

The Stryker's suitability for C-130 transport has led to criticism that the aircraft's range may not meet the 1,000-mile goal. The aircraft's range depends on variables such as the C-130 variant and conditions at the departure airport. In a demonstration conducted in April 2003, a Stryker infantry company, with 21 Stryker vehicles, was transported by C-130s to another airport 70 miles away. Thus proving the vehicle can be transported by C-130, but this demonstration did not address the concern regarding range and airport departure conditions. In addition, the slat armor, when installed, makes the vehicle too large to fit on a C-130, but RPG protection was not a requirement for C-130 transport. The Airbus A400M Atlas is being tested for compatibility with the Stryker in Autumn 2015.

The Stryker is too heavy (19â€"26 tons, depending on variant and add-on features) to be lifted by existing helicopters.

In August 2004, testing was conducted to determine if the Stryker MGS could be airdropped. This testing started with a series of 12-foot drop tests, followed by the US Air Force successfully airdropping an up-weighted Stryker Engineering Support Vehicle from a C-17. Even though this test was a success, none of the Stryker variants have been certified for airdrop. As of 2013 work continues in this area with the capability assumed for the Unified Quest war game.

Tactical

The Stryker can alter the pressure in all eight tires to suit terrain conditions: highway, cross-country, mud/sand/snow, and emergency. The system warns the driver if the vehicle exceeds the recommended speed for its tire pressure, then automatically inflates the tires to the next higher pressure setting. The system can also warn the driver of a flat tire, although the Stryker is equipped with run-flat tire inserts that also serve as bead-locks, allowing the vehicle to move at reduced speeds for several miles before the tire completely deteriorates.

Some criticism of the Stryker continues a decades-long ongoing debate concerning whether tracked or wheeled vehicles are more effective. Conventional tracks have superior off-road mobility, greater load capacity, can pivot a vehicle in place, and are more resistant to battle damage. Wheeled vehicles are easier to maintain, and have higher road speeds. The US Army chose the Stryker over tracked vehicles due to these advantages.

An additional issue is that rollover is a greater risk with the Stryker relative to other transport vehicles, due to its higher center of gravity. The high ground clearance, however, is likely to reduce the damage caused by land mines and improvised explosive devices on the vehicle.

While not amphibious, the Stryker's watertight combat hatch seals allow it to ford water up to the tops of its wheels.

Cost

The unit cost to purchase the initial Stryker ICVs (without add-ons, including the slat armor) was US$3 million in April 2002. By May 2003, the regular production cost per vehicle was US$1.42 million. In February 2012, the cost had risen to US$4.9 million.

Mission

The Stryker family of vehicles fills a role in the United States Army that is neither heavy nor light, but rather an attempt to create a force that can move infantry to the battlefield quickly and in relative security. Brigades that have been converted to Strykers have primarily been light, or, in the case of the 2nd Cavalry Regiment, unarmored Humvee-based cavalry scouts. For these units, the addition of Strykers has increased combat power by providing armor protection, a vehicle-borne weapon system to support each dismounted squad, and the speed and range to conduct missions far from the operating base.

Stryker units seem to be especially effective in urban areas, where vehicles can establish initial security positions near a building and dismount squads on a doorstep.

The Stryker relies on its speed and communications for the majority of its defense against heavy weapon systems. Most Stryker variants are not designed to engage heavily armored units, relying on communication and other units to control threats outside of its classification. One variant is armed with anti-tank missiles.

Brigades equipped with the Stryker are intended to be strategically mobile, i.e., capable of being rapidly deployed over long distances. As such, the Stryker was intentionally designed with a lower level of protection compared to tracked vehicles like the M2 Bradley, but with much lower logistic requirements.

Although the Stryker was designed to be rapidly deployable and not heavily armored, a training exercise in January 2014 demonstrated that in some circumstances, a Stryker brigade with vehicles and infantry using anti-tank missiles could successfully engage a conventional enemy force of tanks, armored vehicles, and helicopters.

Service history

Deployments

• Iraq War, 2003â€"11:
  • The first Stryker brigades were deployed to Iraq in October 2003. 3rd Brigade, 2nd Infantry Division from Fort Lewis was the first to field and deploy the Stryker vehicle to combat in Iraq from November 2003 to November 2004.
  • 3rd Brigade was relieved by 1st Brigade, 25th Infantry Division (SBCT). 1st Brigade served in Iraq from October 2004 to October 2005. Units from this Brigade participated in the Battle of Mosul (2004) and were responsible for the first successful elections in January 2005. The Brigade was awarded the Valorous Unit Award for their tour in Iraq.
  • The 172nd Stryker Brigade Combat Team from Fairbanks, Alaska's Fort Wainwright began its initial deployment in August 2005 to Summer 2006. Their stay was subsequently extended for up to four months and they were reassigned to Baghdad. The Brigade was awarded the Valorous Unit Award for their tour in Iraq.
  • The 3rd Brigade, 2nd Infantry Division re-deployed to Iraq late Spring of 2006 and returned home in September 2007. Like its sister brigades it too was awarded the Valorous Unit Award for operations in Baqubah, Iraq.
  • As part of a three way move, upon redeployment from Iraq, the 1st Stryker Brigade, 25th Infantry Division and the 2nd Armored Cavalry Regiment both cased their colors. The former 1st SBCT, 25th ID was redesignated as the new 2nd Stryker Cavalry Regiment in Vilseck, Germany and the former 2nd ACR was redesignated as the new 4th Stryker Brigade Combat Team, 2nd Infantry Division at Fort Lewis, Washington. During the same period of time, upon redeployment from Iraq, the 172nd Stryker Brigade Combat Team was deactivated and reactivated as the 1st Stryker Brigade Combat Team, 25th Infantry Division, in Fort Wainwright, Alaska.
  • In April 2007, the 4th Brigade 2nd Infantry Division deployed as part of the "surge" in Iraq. This deployment marked the first time the Stryker Mobile Gun System was deployed in Iraq. Also, the 4th Battalion, 9th Infantry Regiment (MANCHU), deployed Land Warrior for the first time in combat.
  • In August 2007, the 2nd Stryker Cavalry Regiment deployed to Baghdad for a 15-month tour, relieving 3rd BDE, 2ID.
  • In December 2007, the 2nd Brigade 25th Infantry division deployed to Iraq.
  • In September 2008, 1-25th Infantry based in Fort Wainwright, Alaska was deployed to Iraq.

• • In January 2009, the 56th Stryker Brigade Combat Team, 28th Infantry Division, from the Pennsylvania Army National Guard, was deployed to Iraq. The 56th SBCT is the only National Guard unit in the U.S. Army to field Strykers.
  • In August 2009, 3rd Brigade 2nd Infantry Division was again deployed to Iraq for a third tour.
  • In September 2009, 4th Brigade 2nd Infantry Division deployed to Iraq for a third tour. The Brigade drove "The Last Patrol" out of Iraq, driving from Baghdad to Kuwait, symbolizing the exit of the "last combat brigade" and ending Operation Iraqi Freedom. The Brigade was awarded the Meritorious Unit Commendation for the tour in Iraq
  • In July 2010, 2nd Brigade 25th Infantry Division once again deployed to Iraq, relieving 3rd Brigade, 2nd ID. 2nd Brigade, becoming the first "Advise and Assist" Stryker brigade.

• War in Afghanistan:
  • The 5th Brigade 2nd Infantry Division was the first Stryker unit sent to Afghanistan, deployed in summer 2009, as part of a troop level increase. The brigade's 1st Battalion, 17th Infantry Regiment suffered the heaviest losses of any Stryker battalion to date. The 5th Stryker Brigade's losses during its one-year deployment were 37 killed and 238 wounded.
  • In June 2010, the 2nd Stryker Cavalry Regiment deployed to Afghanistan relieving 5th Brigade 2nd Infantry Division.
  • In April 2011, 1st Brigade, 25th Infantry Division deployed to Afghanistan to relieve the 2nd Stryker Cavalry Regiment.

Field reports

Due to their use during the 2003â€"11 Iraq War, many reports have come back on their performance, including a negative Washington Post article, a Project On Government Oversight (POGO) report and an article by Defense Industry Daily.

Soldiers and officers who use Strykers defend them as very effective vehicles; a 2005 Washington Post article states that "commanders, soldiers and mechanics who use the Stryker fleet daily in one of Iraq's most dangerous areas unanimously praised the vehicle. The defects outlined in the report were either wrong or relatively minor and did little to hamper the Stryker's effectiveness." In the same article, Col. Robert B. Brown, commander of the 1st Brigade, 25th Infantry Division (Stryker Brigade Combat Team), said that the Strykers saved the lives of at least 100 soldiers deployed in northern Iraq.

The article also states that the bolt-on slat armor is effective ballistic protection, which, at the time of the article, was the main flaw cited by critics. However, a 2003 GAO report to Congress stated that the added weight of slat armor created a mobility limitation in wet conditions due to shortcomings in the vehicle's suspension.

Reports from military personnel and analysts indicate the Stryker is superior to other light military vehicles of US Army regarding survivability against IEDs (improvised explosive devices). Although soldiers have anecdotally referred to Strykers as "Kevlar Coffins."

In 2013 media reports stated that the Stryker Project Management Office had ordered almost $900 million in unneeded or outdated parts due to a failure to control its inventory during the War on Terror.

Variants

The Stryker chassis' modular design supports a wide range of variants. The main chassis is the Infantry Carrier Vehicle (ICV). There have been no proposals yet for an Air Defense variant along the lines of LAV-25 LAV-AD Blazer turret, M6 Linebacker or AN/TWQ-1 Avenger vehicles.

The Stryker vehicles have the following configurations:

• M1126 Infantry Carrier Vehicle (ICV): Armored personnel carrier version that provides protected transport for 2 crew and a 9-man infantry squad, and can support dismounted infantry. Weighs 19 tons, communications include text and a map network between vehicles. It can be armed with 0.50 inch (12.7 mm) M2 Browning machine gun, 40 mm Mk 19 grenade launcher or 7.62 mm M240 machine gun.
  • M1126 Infantry Carrier Vehicle DVH-Scout (ICVV-S): Reconnaissance version of the ICV fitted with an internally mounted Long Range Advance Scout (LRAS) surveillance system and the double v-hull.
• M1127 Reconnaissance Vehicle (RV): used by RSTA Squadrons and battalion scouts, moving throughout the battlefield to gather and transmit real time intelligence/surveillance for situational awareness. The RV's purpose is to anticipate and avert threats, improving the brigade's decisiveness and freedom of maneuver.

• M1128 Mobile Gun System (MGS): Version armed with an 105 mm M68A1 rifled cannon (M68A1E4) (a lightweight version of the gun system used on the original M1 Abrams main battle tanks and the M60 Patton main battle tank), a 7.62 mm M240 machine gun mounted coaxially, an M2 0.50 caliber commander's machine gun and two M6 smoke grenade launchers. The M68A1E4 also features a muzzle brake to assist with recoil and an autoloader, a rare feature on US tank guns. The main gun provides direct fire in support of infantry, engaging stationary and mobile enemy targets, such as bunkers to create a combined arms effect of overmatched firepower that improves survivability of the combat team. The MGS can fire one of its 18 ready 105 mm shells every 6 seconds, and carries 400 rounds of 0.50 caliber and 3,400 rounds of 7.62 mm, and the same C4ISR communications and driver's vision as the ICV. The MGS vehicle is a strengthened variant of the LAV III compared to the standard variant other Stryke r vehicles are based on, but retains commonality across all vehicles in the family.

• M1129 Mortar Carrier (MC): armed with Soltam 120 mm Recoil Mortar System (RMS) provides in-direct fire support to fellow infantry with screening obscurants, suppressive forces and on-call supporting fires (HE, illumination, IR illumination, smoke, precision guided, and DPICM cluster bombs). Precision Guided Mortar Munition (PGMM) attacks point targets at extended ranges with GPS guidance. Organic mortars provide responsive fire support to the maneuver commander and are an ideal system for indirect fire in complex terrain. Vehicles at battalion level also carry the 81 mm mortar for dismounted use, while company mortar vehicles carry the 60mm mortar.
• M1130 Commander's Vehicle (CV): provides commanders with communication, data, and control functions to analyze and prepare information for combat missions; can also link to aircraft antenna/power for planning missions while en route aboard aircraft. Situational awareness helps commanders to coordinate widely dispersed mobile units against decisive enemy points. Deployed as 3 vehicles per brigade HQ, 2 per battalion HQ and 2 per infantry company.
• M1131 Fire Support Vehicle (FSV): is organic to maneuver companies and provides surveillance and communications (4 secure combat radio nets), with target acquisition/identification/tracking/designation being transmitted automatically to the shooting units.
• M1132 Engineer Squad Vehicle (ESV): provides mobility and limited counter mobility support. Integrated into the ESV are obstacle neutralization and lane marking systems and mine detection devices. The ESV with its attachments provides a partial solution to the obstacle clearance role, primarily for clearance of hastily emplaced mines on hard surfaces and rubble, plus will enable the Engineer squad to control future robotic based systems.

• M1133 Medical Evacuation Vehicle (MEV): is the en route care platform for brigade units, part of the battalion aid station, providing treatment for serious injury and advanced trauma as an integrated part of the internetted combat forward formation. attendant's seat that will allow the attendant to change position and visually monitor all patients while the vehicle is in motion. Medical personnel must be seated for safety while the vehicle is in motion, but able to visually monitor patients. Geneva Convention markings can be masked/removed as required.

• M1134 Anti-Tank Guided Missile Vehicle (ATGM): is a missile vehicle armed with the TOW missile to reinforce the brigade's infantry and reconnaissance, providing long-range anti-tank fires against armor beyond tank gun effective range. The separate anti-tank company can also be used to shape the battlefield, reinforce the infantry battalions and reconnaissance squadron (e.g. counter-reconnaissance), serve as a reserve, and of course may counterattack. Vehicle commander independently locates secondary targets while gunner is engaging the primary. After ready rounds are fired, crewman will need to rearm the launcher. A vehicle commander, gunner, loader, and driver operate the ATGM in a tactical environment and to carry equipment if the missile launcher is used in a dismounted mode.
• M1135 Nuclear, Biological, Chemical, Reconnaissance Vehicle (NBC RV): automatically integrates contamination information from detectors with input from navigation and meteorological systems and transmits digital NBC warning messages to warn follow-on forces. The core of the NBC RV is its on-board integrated NBC sensor suite and integrated meteorological system. An NBC positive overpressure system that minimizes cross-contamination of samples and detection instruments, provides crew protection, and allows extended operations at MOPP 0.

Double V-Hull

In response to poor performance against IEDs, the Army began manufacturing and retrofitting Stryker vehicles with a more survivable double v-hull designed underside. Seven Stryker versions are being produced in this configuration; the M1256 ICVV, M1252 MCVV, M1255 CVV, M1251 FSVV, M1257 ESVV, M1254 MEVV and M1253 ATVV. Three variants are not receiving the new hull and will retain their current flat-bottom configuration: the M1127 Reconnaissance Vehicle, the M1128 Mobile Gun System, and the M1135 NBC Reconnaissance Vehicle.

Experimental

• Stryker Self-Propelled Howitzer (SPH): This was a prototype vehicle with turret and ammunition developed by Denel Land Systems. Work stopped after the successful November 2005 demonstration of the prototype.
• Stryker Maintenance Recovery Vehicle (MRV): An armored recovery vehicle based on a Stryker hull. Equipped with a Rotzler TR 200 winch, Magnum 210M crane and hydraulic earth anchor.
• Tracked Stryker: For the Army's Armored Multi-Purpose Vehicle (AMPV) program to replace the M113 APC, General Dynamics created a tracked version of the Stryker. The vehicle kept the highly survivable Double-V hull, and tracks were attached using externally mounted suspension. It was considerably heavier at 70,000 pounds (35 tons, 31,800 kg), but the tracked suspension could handle up to 84,000 lb (42 tons, 38,100 kg) to allow for additional armor, weapons, and cargo. Its powerplant offered 700 horsepower and the vehicle had greater than 60 percent commonality with wheeled Strykers. The Tracked Stryker also had greater fuel efficiency and a wider track for better mobility than the M113. With the suspension mounted externally and the elimination of axles, the Double-V hull's survivability could have been even more effective, as the wheeled version required an interruption in the V-hull to accept axles. The Tracked Stryker was to have competed against the BAE Systems Turretless B radley, but serious efforts on developing the tracked version never materialized because the cost needed to modify the vehicle to meet requirements was too high.
• Stryker Launched Assault Bridge: German manufacturer Krauss-Maffei Wegmann (KMW) has proposed a bridgelaying version of the Stryker that enables tactical vehicles with little or no gap-crossing capabilities to move over divides. The 12 m (39 ft)-long bridge is carried atop the Stryker with hydraulic arms at the front position to launch it and have it in place within two minutes. It can support vehicles weighing up to 40 tons and allow them to cross 11 m (36 ft) gaps.
• Stryker Mobile Expeditionary High Energy Laser (MEHEL): The Army is integrating a directed energy weapon onto the M1131 Fire Support Vehicle version to defend against Group 1 and 2 UAVs (up to 55 lb (25 kg)-class) for mobile forces as the first-ever integration of an Army laser weapon onto a combat vehicle. In an April 2016 test, a 2 kW laser fired from the Stryker shot down 21 drone targets; the vehicle also has an electronic warfare jamming system to scramble drone command signals. A 5 kW version could be operational in 2017, with plans to increase power to 18 kW by 2018.

Operators

Current operators

• Peruvian Army â€" 178 reconditioned flat-bottom Stryker ICVs with .50-caliber machine guns bought in December 2016.
• U.S. Army â€" Seven Stryker Brigades were initially formed. 2,988 vehicles were delivered as of 2009, 4,187 vehicles were in service as of August 2012, and 4,293 were delivered as of November 2012. Production ended at 4,466 vehicles in 2014. In 2009, it was announced that two Heavy Brigade Combat Teams (equipped with M1 Abrams and M2 Bradleys) will be converted to Stryker Brigade Combat Teams by 2013. This will bring the total number of Stryker Brigades to nine. In June 2013, the Army announced that the 4th Stryker Brigade would be deactivated.
  • 2nd Brigade, 2nd Infantry Division â€" final Stryker Brigade formed, formerly 5th Brigade, 2nd Infantry Division.
  • 3rd Brigade, 2nd Infantry Division â€" first Stryker Brigade formed
  • 1st Brigade, 25th Infantry Division, third Stryker Brigade, reflagged from 172nd Infantry Brigade;
  • 2nd Brigade, 25th Infantry Division, fifth Stryker Brigade;
  • 2nd Stryker Cavalry Regiment was the second Stryker unit formed reflagged from 1st Brigade, 25th Infantry Division. Although they are not officially labeled as a Brigade Combat Team because of their unique Cavalry Regiment force structure they are effectively an independent unit parallel to the regular BCTs.
  • 56th Stryker Brigade of the 28th Infantry Division, Pennsylvania Army National Guard (the only National Guard unit to field them).
  • 1st Brigade Combat Team, 1st Armored Division has now become the 1st Stryker Brigade Combat Team as of 2012 and will deploy as a SBCT in 2012.
  • 3d Cavalry Regiment converted to a Stryker Brigade Combat Team in April 2012.
  • 1st Brigade Combat Team, 4th Infantry Division.

Potential operators

•  Chile â€" The Chilean Navy has declared an interest in procuring a number of General Dynamics Land Systems (GDLS) Stryker 8x8 armored vehicles for the Chilean Marine Corps in the M1126 and M1128 variants.
•  Colombia â€" Colombian Army Commander, Alberto José Mejía, confirmed during an interview with El Tiempo, that the army has a group of soldiers in Canada, currently training to graduate on the use of Strykers.
•  Iraq â€" The Government of Iraq has requested, via the Foreign Military Sales program, the possible sale of 400 Stryker ICVs for use by the Iraqi National Police. The order would also include 8 heavy recovery vehicles for use with the Strykers. The Stryker was chosen over a previous request for LAV-25s. The Iraqi Army is also seeking to buy 30 Stryker vehicles. On 25 July 2013, Iraq requested the sale of 50 M1135 NBC Reconnaissance Vehicles for $900 million.

Failed bids

•  Canada â€" Canada originally ordered 66 Stryker Mobile Gun System vehicles in 2003, which were expected to arrive in 2010. However, in 2006 the Canadian Forces asked its government to cancel the MGS acquisition. The MGS was originally intended to be used in the "Direct Fire Unit", which will include Tow Under Armour (LAV III) and MMEV (ADATS on LAV III). The MGS was to provide the direct gun fire capabilities of the retiring Leopard C2 tank. But with the recent demonstrated usefulness of tanks in Iraq and hurried deployment of Canadian Leopard C2 tanks to Afghanistan, Canada announced the purchase of surplus Leopard 2s from the Netherlands. The MMEV project has also since been canceled, and the TUA requirement cut in half.
•  Israel â€" The Israel Defense Forces (IDF) had received three Stryker variants for trials, the first of which were vehicles from early production and did not include add-on armor. A 2004 article in The Jerusalem Post cited an unnamed military source who said the deal was "buried for good", and speculated that the Stryker was not chosen due to a number of shortcomings. In 2008, the IDF began receiving the locally designed and produced Namer heavy armored personnel carriers instead.
•  Lithuania â€" In 2015, Lithuanian State Defence Council chose German made Boxer IFV over the US-made Stryker. Lithuania's requirement that the first batch be delivered in 2017, and the lack of testing of Stryker's 30 mm cannon were reasons.