Stryker

The Stryker is a family of eight-wheeled armored fighting vehicles derived from the Canadian LAV III. Stryker vehicles are produced by General Dynamics Land Systems-Canada (GDLS-C) for the United States Army in a plant in London, Ontario. It has four-wheel drive (8×4) and can be switched to all-wheel drive (8×8).[8]

The Stryker was conceived as a family of vehicles forming the backbone of a new medium-weight brigade combat team (BCT) that was to strike a balance between heavy armor and infantry. The service launched Interim Armored Vehicle competition, and in 2000, the service selected the LAV III proposed by GDLS and General Motors Defense. The service named this family of vehicles the "Stryker".

Ten variants of the Stryker were initially conceived, some of which have been upgraded with v-hulls.

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 be equipped for a variety of operations.[9] An early phase of the plan called for the introduction of an Interim Armored Vehicle (IAV), which was intended to fill the capability gap between heavier and heavily armed, but not easily deployable, vehicles, such as the M2 Bradley, and easily deployable vehicles that are lightly armed and protected, such as the Humvee.[10] The IAV was intended as an interim vehicle until light air-mobile vehicles from the Future Combat Systems Manned Ground Vehicles program came online, none of which did before the program was canceled.[11] Nearly a year and a half behind schedule, the General Motors Defense–General Dynamics Land Systems team was awarded the $8 billion contract in November 2000 to produce 2,131 vehicles of a variant of the Canadian LAV III for equipping six rapid deployment Brigade Combat Teams by 2008.[12] United Defense protested the contract award in December, saying their proposal cost less than half that of General Motors–General Dynamics. The General Accounting Office rejected the protest in April 2001.[13]

U.S. Assistant Secretary of the Army Paul J. Hoeper called the IAV "the best off-the-shelf equipment available in the world in this class", though many in the Army openly wondered whether the vehicles were underclassed compared to the vehicles they might face in battle.[12] In February 2002, the Army formally renamed the IAV as the "Stryker" after two unrelated U.S. soldiers 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.[14]

In 2002, as the Stryker program faced criticism from lawmakers, including former Congressman Newt Gingrich, Pentagon officials mulled reducing the number of planned Stryker Brigade Combat Teams from six to three for a cost savings of $4.5 billion. In October, the Stryker's C-130 air mobility was demonstrated for lawmakers at Andrews Air Force Base. At the Association of the United States Army, Army Chief of Staff Eric Shinseki defended the six-brigade plan and boasted that the C-130 could carry a Stryker every way but sideways.[15]

Four brigades were funded in the DoD's budget proposal for fiscal year 2004, with Secretary of Defense Donald Rumsfeld deferring a decision on two additional until July 2003. In May, the Army readied the Stryker for initial operating capability at Fort Polk. The New York Times noted the swiftness with which the program had proceeded from its inception in 1999.[16]

In November 2003, 311 Stryker vehicles were deployed in the Iraq War, where they saw mixed success.[17] Never designed for front-line combat, the vehicles were nevertheless pressed into counterinsurgency roles for which there was an unmet need.[18]

Unexpectedly fierce resistance by insurgents prompted field upgrades to the vehicle's armor. To counter the threat of rocket-propelled grenades, General Dynamics developed slat armor, which added 5,000 lb (2,270 kg) to the vehicle weight. The upgrades came at a cost: in addition to hindering mobility in the field, the additional weight ruled out transporting the vehicle by C-130.[18]

In February 2005, Army Chief of Staff Gen. Peter J. Schoomaker told the House Armed Services Committee that "we're absolutely enthusiastic about what the Stryker has done." However, a leaked U.S. Army report from December 2004 said the Stryker was "effective and survivable only with limitations for use in small-scale contingencies." The report, which drew from feedback from Stryker personnel in Mosul, described a litany of design flaws, and said the effectiveness of the vehicles was "getting worse not better."[17]

The Stryker 105 mm M1128 Mobile Gun System (MGS) moved into low-rate initial production in 2005 for evaluation,[19] and entered full production in 2007.[20] General Dynamics Land Systems-Canada assembles the Stryker for the U.S. Army in a plant in London, Ontario.[21]

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.

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.[22] 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.[23]

As of 2011, over 1,000 Stryker vehicles have been rebuilt by Anniston Army Depot and returned to operations.[24]

Throughout its years in service, the Stryker has undergone various survivability upgrades and received "kit" applications designed to improve the vehicle's ability to withstand attacks.[25]

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-absorbent, mine-resistant seating, non-flammable tires, an upgrade to the remote weapon station that allows it to fire on the go, increased 500 ampere electrical generation, a new solid-state power distribution system and data bus, and the automotive and power plant systems improvements to support one-fourth greater gross vehicle weight. 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.[26]

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.[27] In March 2010, it was reported that General Dynamics and Army were working to incorporate a double V-hull into the Stryker design.[28][29][30][31] In July 2010 the Army awarded a $30 million contract to GDLS to start production of the new hull.[32]

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 deployment of the new Stryker version.[33] The upgrade also added significant weight to the vehicle, which can cause it to sink into soft ground.[34]

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.[35][36][37]

By August 2012, the Army's Stryker fleet included over 4,187 vehicles, with 10 flat-bottom variants and seven 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 extant 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.[38] 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.[39]

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.[40] 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.[41] Upgrading the fourth brigade also kept the production line active through 2018, whereas deciding to upgrade after the line had closed would be more difficult and costly from reopening it.[42] The upgrades of the engine and power generator, 60,000 lb (27,000 kg) suspension, and DVH designate the vehicle the Stryker-A1.[43] 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.[44] By September 2020, half of the 2nd Brigade, 4th Infantry Division had fielded the third-generation Stryker DVHA1 variant.[45]

On 28 February 2018, the Army announced that Stryker vehicles would be modified with sensors and weapons to fulfill an interim Maneuver-Short-Range Air Defense (M-SHORAD) requirement. This is in response to a capability gap identified in Europe against Russian unmanned aerial vehicles (UAVs). With the previous focus on fighting in the Middle East, the U.S. Army had neglected SHORAD capabilities and in future conflicts it is feared they would not be able to rely on air dominance to counter enemy aircraft. In addition to deploying AN/TWQ-1 Avengers and fielding man-portable Stinger missiles, Strykers are to be upgraded to buy time to build a lasting mobile air defense solution.[46] Because the unarmored Humvee-based Avenger lacks survivability and range to keep up with maneuver forces and hold off enemy aircraft in contested territory, four battalions totaling 144 Stryker SHORADs are planned, with the first battery of 12 systems fielded by 2020; the Stryker platform was chosen because it has better protection and in regards to size, weight and power considerations, especially for the possibility of integrating a directed energy weapon in the future. The first unit to be equipped with them will be the 4th Battalion, 5th Air Defense Artillery Regiment. The Army planned to select the weapons configuration to be fitted onto the vehicle by late 2018.[47]

In June 2018, the Army chose Leonardo DRS to supply the mission equipment package, which partnered with Moog Inc. to integrate the Reconfigurable Integrated-weapons Platform (RIwP) onto the vehicle. The system can be fitted with a Stinger pod and Longbow Hellfire missile rails and comes equipped with a 30 mm M230LF chain gun and the 7.62 mm coaxial machine gun, as well as non-kinetic defeat capabilities and a Rada onboard multimission hemispheric radar. The Army chose DRS because of the flexibility of the reconfigurable turret to allow for growth opportunities and alternate weapon options, it posed less intrusion to the existing vehicle platform, as they have a desire to keep the Stryker as common across the fleet as possible, and it provided increased protection as the crew can reload ammunition under armor. All 144 M-SHORAD systems are planned to be delivered by 2022.[48] The turret can mount one four-shot Stinger pod or two Hellfire missiles on either side, and reloading of the M230LF and Stingers can be done through roof hatches giving partial protection. The system can act in a secondary anti-vehicle role, as the 30 mm cannon is larger than the 25 mm gun mounted on the M2 Bradley and the Hellfire has greater range than TOW missiles typically used by ground vehicles.[49]

On 30 September 2020, the Army awarded General Dynamics the IM-SHORAD contract worth $1.2 billion to deliver 144 vehicles over five years; the first order was for 28 vehicles for $230 million.[50] The first four Stryker M-SHORAD vehicles were deployed to Germany in April 2021 as part of the 5th Battalion, 4th Air Defense Artillery Regiment under the 10th Army Air and Missile Defense Command. A full battalion will be fielded in September 2021.[51][52]

In 2022, the Army plans to field the Directed Energy Maneuver SHORAD (DE-MSHORAD), a Stryker equipped with a 50 kW laser to protect forward deployed soldiers from UAVs and rocket, artillery, and mortar (RAM) threats.[53] A combat shoot-off of the laser-equipped Strykers facing realistic scenarios was conducted in July 2021.[54]

The Stryker is based on the LAV III light armored vehicle, which in turn was based on the LAV-25 series.

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 General Dynamics Land Systems (GDLS) 105 mm automatic gun called the M1128 Mobile Gun System.

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.[55] Because of obsolescence concerns, the Caterpillar 3126 engine was recently replaced by a Caterpillar C7 engine and the Allison 3200SP transmission.[56]

Pneumatic or hydraulic systems drive almost all of the vehicle's mechanical features; for example, a pneumatic system switches between 8×4 and 8×8 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.[citation needed ]

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.[57]

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.[58]

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.[59] 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.[55][60] 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.[61] The issue was eventually resolved later in 2003 when DEW Engineering was selected as the new, exclusive supplier for the ceramic armor.[62]

In addition to the integral ceramic armor, optional packages have been developed. These include slat armor[64] 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.[59]

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.[65] In 2005, slat armor for the Stryker vehicles was designed and developed by the Army Research Laboratory and the Aberdeen Test Center in Maryland to further protect them from RPGs.[66] The cage is placed 50 cm ahead around the vehicle, allowing a RPG warhead to explode at a safe distance from the vehicle.[67] In addition, the slat armor on the Stryker vehicles is reportedly effective against HEAT rounds. 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.[68]

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).[69][70]

In spring 2016, a Stryker regiment deployed to Europe with the Saab mobile camouflage system (MCS), which both changes its physical appearance to better blend into the environment and incorporates properties that improve signature management against long-wave and mid-wave thermal sensors, near-wave and short-wave infrared, and radar. Further tests will influence the Army to decide whether to pursue acquiring the camouflage system through a program of record.[71]

In 2016, Artis LLC's Iron Curtain active protection system was selected for integration onto the Stryker as an interim system until the Army develops the Modular Active Protection System (MAPS); Iron Curtain differs from other APS by defeating projectiles just inches away from the vehicle, rather than intercepting them several meters out.[72] However, in August 2018 the Army decided not to continue qualifying Iron Curtain onto the Stryker due to maturity issues with the system.[73]

With the exception of some specialized variants, the primary armament of the Stryker is a Protector M151 Remote Weapon Station with .50 in (12.7 mm) M2 machine gun, 7.62 mm M240B machine gun, or 40 mm Mk 19 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.

In September 2017, Raytheon fired Stinger missiles it had integrated into a Stryker-mounted Common Remotely Operated Weapon Station (CROWS) to intercept airborne targets in a demonstration, turning the vehicle into a short-range air defense system. The Army is considering the capability and if selected could be rapidly fielded within two years.[74][75]

In August 2018, 86 Strykers began fielding with a CROWS turret adapted to be able to fit a Javelin anti-tank missile tube, allowing the vehicle to fire the weapon instead of needing dismounted troops to use it.[76]

While the Stryker MGS gives medium brigades heavy firepower, the baseline infantry carrier vehicle has a light armament. Stryker program officials pursued mounting 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 will give greater firepower without needing to add a turret. The plan was 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.[77] The Army planned to test stabilized 30 mm cannons in early 2014, including Kongsberg Protech Systems' Medium Caliber Remote Weapons Station (RWS). Kongsberg, which makes the Stryker's M151 RWS joined with Stryker manufacturer, General Dynamics 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 hatches.[78] The autocannon is fed by two magazines holding armor piercing and high explosive ammunition, each carrying 78 rounds, with another 264 rounds stored in the hull.[79] 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 0.50 in (12.7 mm) machine gun at ranges of 600 to 1,550 meters (660 to 1,700 yd), with four rounds in five-round bursts hitting the targets.[80]

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. Reviews of the effectiveness of these new turrets in Stryker companies informed decisions regarding the upgrade of more Strykers across the nine Stryker Brigades.[81][82] The remote turret requires a modification of the hull roof, and adds an additional two tons of weight[83] with an upgraded suspension and wider tires.[84] Outfitting the first Strykers with Mk44 Bushmaster II cannons was planned to occur during the next two years, it was stated in 2015.[85] The cannon, which can engage light armored vehicles out to 3,000 meters (1.9 mi).[84] is also able to fire airburst rounds that explode above a target to hit enemy troops behind barriers[86] and can defend against unmanned aerial vehicles.[87] The Kongsberg turret and Orbital ATK XM813 variant of the Mk44 Bushmaster were officially selected in December 2015.[88] Kongsberg later renamed the turret system to RT40 (Remote Turret).[89] The first upgraded Stryker, designated XM1296 "Dragoon", was delivered for testing on 27 October 2016, with fielding to begin in May 2018.[90] The first Infantry Carrier Vehicle - Dragoon (ICVD) was delivered to the 2CR in Germany on 8 December 2017.[91]

In April 2019, the Army decided to add cannon armament to Stryker DVH ICVVA1 vehicles in three brigades; the first is planned to be equipped in 2022.[92] On 3 June 2021, the Army chose Oshkosh Defense to supply its Medium Caliber Weapon System (MCWS), the previous GDLS/Kongsberg team which supplied turrets to the 2nd Cavalry Regiment competed in the full-and-open competition but was not chosen to deliver more.[93][94][95] The June contract award is worth up to $942 million over six years. As of the award date, the army had approved plans to outfit three brigades with 83 Medium Caliber Weapon Systems (MCWSs) each but the contract covers up to six brigades worth of vehicles if the service decides that is how it wants to proceed. The initial order calls for 91 vehicles for approximately US$130 million, and the army will provide the Oshkosh-led team with the vehicles and the XM813 cannon for integration. On 10 August 2021, Oshkosh received an additional US$99 million to cover the modification of 83 further vehicles, bringing the total number of vehicles under contract up to 174.[96] The Oshkosh-led team provides a turret based on Rafael's Samson family of turrets but customized for the army.[96]

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.[9]

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.[97] 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.[97] This proved that the vehicle can be transported by C-130, but did not address the concerns 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 was being tested for compatibility with the Stryker in Autumn 2015.[98]

The Stryker is too heavy (19–26 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.[99] 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.[100]

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.[101] 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.[102]

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.[103]

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

The unit cost to purchase the initial Stryker ICVs (without add-ons, including the slat armor) was US$3 million in April 2002.[citation needed ] By May 2003, the regular production cost per vehicle was US$1.42 million.[104] In February 2012, the cost had risen to US$4.9 million.[4]

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.[105][106]

A standard Stryker Brigade typically consists of: 130 Infantry Carrier Vehicles; 9 Anti-Tank Guided Missile Vehicles; 27 Medical Evacuation Vehicles; 12 Engineer Squad Vehicles; 32 Commander's Vehicles; 36 120 mm Mounted Mortar Carriers; 56 Reconnaissance Vehicles; 13 Fire Support Vehicles; three NBC Reconnaissance Vehicles; and 12 105 mm Mobile Gun Systems.[45]

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 the Stryker 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.[citation needed ]

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.[107][108]

Due to their use during the 2003–11 Iraq War, many reports have come back on the Stryker's performance.[112][113] Soldiers and officers who use Strykers defend them as very effective vehicles;[114] 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.[115] The article also states that the bolt-on slat armor is effective ballistic protection, which was the main flaw cited in 2009 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.[116]

Reports from military personnel and analysts indicate the Stryker is superior to other light military vehicles of the US Army regarding survivability against IEDs (improvised explosive devices).[117][118] Soldiers have anecdotally referred to Strykers as "Kevlar Coffins", affording the Stryker vehicle its own rank-and-file pseudonym, a time-honored tradition among American servicemembers.[119]

The non-partisan Project on Government Oversight received unexpectedly positive reviews when it spoke to soldiers who served in Strykers: "The Stryker’s fantastic. It has incredible mobility, incredible speed..." "We’ve been hit by 84 suicide VBIEDs (...car bombs) have hit Strykers, and I’ve had the greater majority of soldiers walk away without even a scratch. It’s absolutely amazing. If I were in any other type vehicle, I would’ve had huge problems," said Colonel Robert Brown, commander of the 1st Brigade of the 25th Infantry Division. Maj. Doug Baker, executive officer of the 5th Battalion, 20th Infantry Regiment in 3/2 said, "When you rolled out (of) the gate, you were fairly confident that the vehicle was going to take care of you… I’m familiar with what a Bradley can do. It’s a fantastic vehicle, but I would take a Stryker over it in Iraq any day."[120] Crew members of the Stryker Mobile Gun System attest to its "seamless" ability to fill the high-mobility niche between main battle tank and armored personnel carrier.[121]

As of 2005, the Stryker vehicle logged more than 27 million combat miles, with operational readiness rates greater than 96 percent.[120]

The Stryker chassis' modular design supports a wide range of variants. The main chassis is the Infantry Carrier Vehicle (ICV).

The Stryker vehicles have the following variants:[122]

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.[35][124]

  United States – Used by the U.S. Army. Seven Stryker Brigades were initially formed.[143] 2,988 vehicles were delivered as of 2009[update],[144] 4,187 vehicles were in service as of August 2012,[38] and 4,293 were delivered as of November 2012. Production ended at 4,466 vehicles in 2014.[5] 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.[145] 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.[146] The following units use Stryker vehicles:

  Thailand – In May 2019 Royal Thai Army ordered 37 refurbished M1126 Infantry Carrier Vehicles from U.S. Army and is also to receive 23 more M1126 vehicles.[148] Around 60 Strykers were delivered to Bangkok via C-17s with an option for 30 more Strykers for free while Thai military personnel are to be trained in the US about operating the vehicles.[149]