FGM-148 Javelin

The FGM-148 Javelin is a guided missile featured in Call of Duty 4: Modern Warfare, Call of Duty: Modern Warfare 2, Call of Duty: Modern Warfare: Mobilized and Call of Duty: Modern Warfare 3.

Call of Duty 4: Modern Warfare
The FGM-148 Javelin appears exclusively in the single-player campaign of Call of Duty 4: Modern Warfare, most notably in the missions, "The Bog" and "Heat" where the player's objective is to take out four enemy T-72 tanks. It can also be found in "Safehouse", and "All In". It cannot be fired in enclosed spaces, or a message saying that there isn't enough room will appear. Occasionally, such as in "Heat", the Javelin missile can get 'hung up' on a roof if fired too close, due to the missile not having the chance to ignite.

Campaign
The FGM-148 Javelin returns in Call of Duty: Modern Warfare 2. The Javelin appears in the level "Of Their Own Accord", where the player is ordered to snipe Russian soldiers armed with Javelin launchers. Shortly after, the player gets an opportunity to pick up a Javelin and destroy several BTR-80s and Mi-28 gunships attacking the Washington Monument Evacuation Site. The Javelin is later mentioned and heard, but not directly seen in "Loose Ends", where Archer and Toad use them to destroy Ultranationalist vehicles.

A Javelin Launcher is available in the "Museum", but unfortunately the Javelin cannot lock onto any location or object inside the museum and therefore cannot fire.

Multiplayer
The Javelin is the second to last launcher obtained, being unlocked at level 50. Similarly to the Stinger, it can lock onto aircraft. A short beeping noise will confirm when the player has a solid lock on anything they see when they aim down the sight. This effectively allows the player to fire in cover, providing there is enough room to fire the rocket. It can shoot down attack helicopters and UAVs in a single hit and the Pave Low and the AC-130 in two, or sometimes even in only 1 if it tricks the target or if it has already deployed its flares. The Javelin can destroy enemy Harriers, although due to the size of the Harriers fuselage, the Javelin missile may miss and then turn and try to destroy the harrier in mid-air. If a Javelin missile is launched but is beaten to its target by, say, the faster Stinger missile and no other target remains, it will circle the area with sharp turns and then crash down on the level in a highly unpredictable fashion. Unfortunate players may find themselves committing suicide or team killing to no fault of their own. More fortunate players can be rewarded by a highly unexpected random kill on a target far beyond the line of sight. This risk (or chance, depending on which end of the missile the player ends up) is, for obvious reason, compounded on smaller levels.

However, it has a second function which the Stinger does not have: the Javelin is able to lock onto areas on the ground, effectively making it a sophisticated, shoulder-fired mortar. Once fired, the missile will fly upwards and hit the target area several seconds afterwards, unleashing a fairly large and lethal explosion, similar to, yet smaller than that of the Predator Missile killstreak. When used properly and tactically, a Javelin-user can fire at a safe range and hammer down on a group of enemies. Because of the nature of the weapon, it will always hit the target from above, so make sure the target has line of sight to the sky (in fact, this can even allow the player to hit locations that would normally be sheltered against launchers, such as walled-in rooftops, buildings with derelict roofs, or even skylights on Terminal). However, using Danger Close can increase the lethality of the explosion. It is worth noting that the delay between firing and impact is considerable, even a hindrance to reliably getting kills, so it is recommended to use it more as an anti-camp solution or against high traffic objectives like bomb sites or Domination flags. When firing the Javelin, however, the user must be careful to have enough vertical clearance as the rocket will fly forward a short distance then straight upwards. If there is a roof or overhang above and in front of the user, the Javelin will detonate, killing the user and enemies around them. Also an explosion will occur when the Javelin is fired uphill, as it will go straight forward before its ascent. Less frequently, some teams or single players will launch Javelin missiles at the start of a match on a specific area of a specific map or an objective in hopes of killing small or large groups of enemy players.

Contrary to popular belief, the Javelin does NOT lock on to enemy players. Many players believe in this concept, and either continuously scan the area with the Javelin (with no such target, or fire immediately once the beep is sounded, believing that they will secure a kill).

Unfortunately, while the Stinger missile comes with two missiles upon spawning, the Javelin only has one, making shooting killstreaks like the Pavelow and the Chopper Gunner more difficult since those require two missiles if the trajectory of the fired rocket is not perpendicular to the target (the first missile to expend its defensive flares). The Javelin has an unusual loading behavior. A user can actually carry 2 missiles, one in reserve and one in the launcher. After spawning, the player's missile is actually in the reserve slot. Upon drawing the weapon for the first time, the missile is loaded into the launcher, opening the reserve slot. Additional missiles can only be acquired if the reserve slot is open. Because of this using Scavenger and the Javelin can be a little confusing. The player must draw the launcher and let the reload complete at least once to get a second missile. After firing, the Javelin will switch back to the primary weapon without reloading. This means that after firing the launcher, a reserve missile, if present, will NOT be loaded into the launcher by default which means the reserve slot will remain full, which means running over an ammo bag will NOT increase the user's missile count to two. The user must switch back to the Javelin, wait for the long load animation to complete, then run over the ammo bag to pickup the second missile. The Scavenger perk does NOT give the Javelin more starting ammo, however the player can run over Scavenger packs at the start to gain the extra rocket if needed.

It is recommended to check the surrounding area before the player fires. Ensure that there is nothing above that will block the rocket and in turn causes the player to commit suicide. Always move to somewhere high or the corner of the map to fire, so that there will be less obstructions. However, if doing random shots, this will decrease the chances of a kill.

The Javelin can be useful for different scenarios besides scoring random kills and destroying air support. In objective game modes like Demolition, one can get to a high point and use it on a bomb site if defenders are flooding to the area to disarm it. An example would be Highrise. Get to the top of the office building or the top of the crane outside the buildings and shooting it from there will give the player more space to shoot from and have a wider range of options to shoot the missile at. A map more suited for this would be Rust as the small, open areas and big lethal explosion radius increase the chance of a kill or two.

The Javelin can be highly lethal in Hardcore both because it kills more readily and because players tend to move less, giving the missile a larger time window in which to reach them, but it can also prove disastrous if the player does not take the risk of Team Killing into account. Once launched, the teammates of the player who launched the Javelin have no way of knowing where it is heading. They will have to rely on the player aiming it correctly in the first place and not targeting either where they are or where they are clearly heading. Pressing Start and checking the minimap ahead of firing is vital to avoid excessive fratricide.

Call of Duty: Modern Warfare: Mobilized
The Javelin makes an appearance in Call of Duty: Modern Warfare: Mobilized as one of the two launchers in game, the other one being the RPG-7. In game, the Javelin is available exclusively to single player, though used more extensively than on the console versions. The Javelin is only used in the levels "Interception" and "Hostile Territory". Despite being in these missions, its use is limited only to the vehicles the player is ordered to fire upon. Even after cornering the nuke's vehicle in "Interception", the nuke will be set off anyway by the militia there. Upon firing the Javelin, the ADS button on the touch screen disappears, preventing one from using the ADS until a fresh rocket is loaded.

In terms of function and power, it is the same as the console versions, but it differs slightly in appearance. Possible targets are shown in black boxes instead of green, there are no arrows pointing to the targets that are out of view, there is a yellow cross-hair on the screen, and there is no restriction to where it can be fired. But when fired in an enclosed area, the player can kill or injure themselves.

Call of Duty: Modern Warfare 3
The FGM-148 Javelin returns in Modern Warfare 3. It still functions the same as it did in Modern Warfare 2. It is unlocked at Level 24. The Javelin's rocket also drops much quicker in this game than its predecessors.

Trivia

 * In Call of Duty: Modern Warfare: Mobilized, while aiming through the sights, if the player gets hurt their HUD will be gone except for crouch/stand.
 * One can actually hold one's breath while using the Javelin, just like sniper rifles, however this has little effect.
 * The Javelin will occasionally miss enemy air support. In some instances, it can go right through enemy Harriers.
 * In Call of Duty: Modern Warfare 2, the Javelin has writing on the plaque under the scope. The writing is a reference to Infinity Ward.
 * In Call of Duty: Modern Warfare 2, it is possible to get a headshot with the Javelin.
 * In Call of Duty 4: Modern Warfare, one of the quotes when the player dies states that the cost of a single Javelin missile is $88,000 USD.
 * In Call of Duty 4: Modern Warfare, if the player puts night vision on then aims down the Javelin's scope, the "Day" icon on the HUD will no longer be lit, while the "Night" icon will be lit.
 * When used with the Danger Close perk, the blast radius is just under that of a Predator Missile.
 * In Call of Duty: Modern Warfare 2 (when locked on to helicopters), the Javelin's HUD indicates that its firing in direct-fire mode. Javelin's can switch from top attack to direct attack, allthough in game they are mostly seen used in top attack.
 * In "The Bog" in Call of Duty 4: Modern Warfare, players that use the "give all" cheat on the PC will receive a Javelin that cannot lock-on and is unable to fire. It is similar to the Stinger that looks like an AT4 in "Game Over".