The FGM-148 Javelin is an anti-tank guided missile (ATGM) launcher.
The FGM-148 Javelin is a man-portable fire-and-forget missile used primarily by the U.S. military. The weapon system consists of two major parts: the disposable launch tube missile, and the reusable Command Launch Unit (CLU, pronounced "clue") which consists of a 4x optical and 4x or 9x IR (thermal) sight. The CLU can be used separately as a low-powered optical or thermal telescope.
To use the system, the operator mates the CLU to a Javelin launch tube. After locating his target and roughly centering it in the 4x optical or thermal sight, he then presses the first trigger, which engages the 9x thermal sight and the CLU's thermal locking system. The CLU then locks on and feeds target and flight data to the missile. After a successful lock, the missile can be fired with the second trigger. Once fired, the missile uses the data loaded by the CLU and its own thermal seeker to engage the target.
The missile can be fired in two different modes, selectable by the operator before lock-on. The CLU can program an arcing top-attack flight profile against armored vehicles (attacking the top armor which is generally thinner), but can also take a direct-attack mode for use against buildings or fortifications. This fire mode is also useful in urban or forested areas, where the missile might impact an obstruction en route to the target unless fired straight. The missile also has the ability to engage helicopters in the direct attack mode. It reaches a peak altitude of 150m in top attack mode and 50m while in direct fire mode. The Javelin missile uses a tandem warhead designed to defeat the reactive armor found on most modern tanks. The precursor charge explodes on contact, causing any reactive armor it has hit to detonate and expend its energy, allowing the primary warhead to penetrate through and make direct contact with the base armor before detonating. The Javelin was used in the 2003 Invasion of Iraq, with devastating effects on Iraqi-variant T-72 and Type 69 Main Battle Tanks.
The missile is ejected from the launcher by a small charge so that it reaches a safe distance from the operator before the main rocket motors ignite; this is known as a "Soft Launch Arrangement." This makes it harder to identify the launcher and allows it to be fired from within buildings without extensive preparations. However, back-blast from the launch tube still poses a hazard to nearby personnel as it is powerful enough to dismember limbs. Thanks to this "Fire and Forget" system, the firing team may move on as soon as the missile has been launched.
The missile system is carried most often by a two man team consisting of a gunner and an ammo bearer, although it can be fired with just one person if necessary. While the gunner aims and fires the missile, the ammo bearer scans for prospective targets and watches for threats such as enemy vehicles and troops.
In 2014, British PMC Praying Mantis forces utilized the FGM-148 Javelin in their mission in the Middle East, against a BMP-3 used by a rival PMC group that forced the former to retreat earlier, at the Crescent Meridian.
Behind the scenes
The FGM-148 Javelin is featured in Metal Gear Solid 4: Guns of the Patriots and is very much unlike the real life version; rather than a multi-use launcher using self-guided, fire-and-forget missiles, it is depicted as a disposable single-use device which fires manually guided missiles that steer towards where the weapon is pointed, much like its predecessor, the M47 Dragon. Conversely, in Metal Gear Solid: Peace Walker, the M47 is more akin to a real Javelin, being capable of fire-and-forget. PMC forces in Act 1 are shown using the Javelin in top-attack mode against an oncoming militia BMP-3, but Snake cannot use it in this way. As the most powerful of the game's four missile launchers, it is especially useful for taking out hardened enemies, such as Gekko (be wary of Gekko with deflection capability). It can be purchased from Drebin's shop, or on very rare occasions, found being used by PMC soldiers.
The Javelin can be first found in Act 1, in the Crescent Meridian section, where the militia brings out a BMP-3 to clear out Praying Mantis forces. One of the buildings on the left side of the street contains a PMC soldier armed with a Javelin; he'll likely be the first to get a shot off at the BMP, unless the player is able to take him out quickly enough. Keep the Solid Eye equipped, as it will come in handy in locating all of the anti-armor threats in the area. However, even if Solid Snake manages to guide the BMP past all the Javelin teams, a final team will open fire with missiles in top-attack mode from a high bridge and destroy it.
The Javelin is hidden in the same building that the anti-armor PMC soldier was in. The player must use caution when going for it, as there's a sniper just to their right at the end of the ladder. It can also be found in the shack in Act 2 where the player acquires the XM8 Rifle.