EMP

The EMP (ElectroMagnetic Pulse) is an unlockable killstreak reward in Call of Duty: Modern Warfare 2. Requiring a killstreak of 15, the EMP disables all enemy electronics. Hostile players will have no HUD, and electronic scopes (such as the Red Dot Sight) will be disabled. Their vision will also be slightly fuzzy. Any enemy sentry guns will be destroyed and all hostile aircraft will crash. Enemy players will be unable to activate their own killstreaks while they are affected by an EMP. The EMP effects last for 60 seconds. Strangely, it doesnt affect friendlies.

An EMP is featured in the single-player missions Contingency and Second Sun, greatly affecting the Russian advance in the Russo-American War.

Weapon Attachments

 * Red Dot Sight - "Red dot" disappears (exceptions - the F2000 and TAR-21)
 * Holographic Sight - Targeting reticle disappears.
 * ACOG Scope - Red cross hairs disappear, but the black cross hairs remain.
 * Thermal Scope - Thermal vision is disabled, but crosshairs remain, essentially becomes a standard sniper scope.
 * Heartbeat Sensor - Inoperative, static fills the screen.

Weapons

 * Stinger - Unable to lock on to targets. (Unable to fire.)
 * Javelin - Unable to lock onto enemies or vehicles. (Unable to fire.)
 * AT4 - Unable to lock on to enemy vehicles, though still able to fire in free aim.

Killstreaks

 * All killstreak rewards will be destroyed if they are active at that moment, but the Emergency Airdrop cargo plane will be unaffected and still proceed to drop its load.
 * No killstreak rewards can be activated during the duration in which the EMP is active.
 * The Tactical Nuke is a unique case. While EMP is active, the nuke cannot be activated. However, if the nuke has already been launched, the EMP will not disable it, and the countdown will continue until endgame.
 * If an AC-130 is being used by a player at the time of the EMP detonation, the player is forced to stop controlling the plane and will come back to their body. The AC-130, however, will remain above.

Equipment

 * Claymore - Will not detonate if tripped, but the trip lasers remain active.
 * C4 - Remote detonator is disabled, but can be shot to explode.
 * Throwing Knife - Will fall to the ground.

Trivia

 * An EMP should realistically not have any effect on ACOG scopes. This is because they are illuminated by tritium, a radioactive isotope of hydrogen, and contain no electronics like the other optics in the game.
 * An EMP does not affect the digital wrist watches worn by some of the forces like the Ranger.
 * If the player looks outside the map immediately after an EMP is deployed (by either team), they can see a nuclear explosion identical to the one seen in Second Sun in the distant sky.
 * It is odd that setting off an EMP does not affect Semtex grenades as they are detonated electronically.
 * In reality, an EMP blast would not disable electronic devices that are insensitive to excess voltage.
 * The handguns' sights will not have the 3 dots on them once an EMP is detonated; this is not accurate as the dots are painted or tritium-illuminated.
 * Strangely enough, the EMP sometimes affects the televisions in Terminal, but not all the time.
 * The EMP in Modern Warfare 2 is classified as the E1 component of an EMP, as the E2 component is more lightning-like, and the E3 component has a much slower pulse.
 * The EMP is the highest killstreak available in a Care Package. However, the EMP is unobtainable from the Emergency Airdrop.
 * The title obtained when completing "Blackout: II" is called "Starfish Prime," which was a high-altitude nuclear test that caused a resulting EMP to affect most of Hawaii.
 * Using two EMPs will complete the Blackout I challenge, unlocking the callsign "Chick Magnet."
 * It is strange that the Throwing Knife is affected by an EMP, since it isn't an electronic device. Meanwhile, the knife used to melee still works.