Attack Helicopter

The Attack Helicopter is a killstreak reward in Call of Duty: Modern Warfare 2 and Call of Duty: Black Ops. It replaces the Helicopter from Call of Duty 4: Modern Warfare.

Call of Duty: Modern Warfare 2
The Attack Helicopter returns as a 7-kill streak reward and is identical to its Call of Duty 4 counterpart in appearance. It is generally less effective than its Call of Duty 4 counter-part, mainly due to the Cold Blooded perk. In Modern Warfare 2, the Harrier Strike, another 7-kill streak reward, is used more often than the Attack Helicopter, as it features a 2-round airstrike (w/o direction, unlike the Precision Airstrike), followed by a hovering Harrier. It appears to fire FMJ rounds, as evidenced by the sound it makes when the bullets impact. The Attack Helicopter's (as well as the Harrier) main weakness is its lack of flares. A single Javelin, Stinger missile (or two AT4, RPG-7 missiles) will bring it down, as well as a single Predator Missile. It will also linger around for a little longer than its Call of Duty 4 counterpart. Task Force 141, Rangers, and SEALs use the AH-1W(4B) Super Cobra. Militia, OpFor, and Spetsnaz use the Mi-24 Hind.

This killstreak can be very effective on maps that have a lot of buildings such as Invasion and Karachi as the attack helicopter moves a lot around the map, meaning it is quite hard sometimes when players armed with Stinger or Javelin missiles try to take them down. However, the helicopter is unlikely to kill anyone as they will most likely be inside, and it is not that hard to destroy as it can be shot before it can even get in the map, and it doesn't move that fast.

Harriers can be a lot more sensitive to enemies than the Attack Helicopter can, further increasing the Harrier's advantage over this killstreak.

Call of Duty: Black Ops
The Attack Helicopter or Cobra by multiplayer announcers, is a seven killstreak (six with Hardline) that is immediately available to the player, along with the Spy Plane and Care Package. When activated, the user will choose a certain area for the Attack Helicopter to hover over for a short period of time. This comes in handy when the player needs to protect a position, such as a bombsite or flag. On the small maps and many of the medium-small maps, placing an Attack Helicopter in the center of the map will allow it to cover nearly the whole playing field. Due to the function of the Ghost perk, and the rarity of players using its pro version, Attack Helicopters are quite deadly if the opposing team or players do not neutralize it in a timely manner. Destroying the Attack Helicopter can be accomplished with generous amounts of small arms fire or 2 rockets or missiles from a launcher weapon. The Attack Helicopter can evade a missile or rocket once every thirty seconds or so via flares, making a team effort the most effective method. Finally, identifying friendly or hostile Attack Helicopters is possible by observing the dorsal stripe and camouflage colors; green markings on tan camo for friendly, and red markings on gray camo for hostile.

Trivia

 * It is interesting to note that the Black Ops cockpit is near-fully rendered -- it has the control board and the seats, but the detail level is very low.
 * When the player scores a kill with the Attack Helicopter in Black Ops, the pilot will notify him with the kill by saying something like "Tango down!"
 * One of the main reasons of the Harrier being used more than the Attack Helicopter is the kill time, the Harrier only fires in short bursts for a kill, and the Attack Helicopter will often take slightly longer.
 * In Black Ops, the Attack Helicoptor seems to be similar to a Harrier due to the fact you can pick the location and the helicopter will hover over that area for most of it time only moving a little bit.