Hydra

The Hydra is a VTOL fighter jet in Grand Theft Auto: San Andreas.

Design
The Hydra is evidently a jet-powered military aircraft, bearing roundels of the United States Air Force on its wings, with armament containing 2 air-to-air missiles (evidently AIM-9X Sidewinders). The Hydra is suggestively based on the British Harrier fighter jet. This is further proven by the code that is used to spawn it in the PC version, "Jumpjet", which is a nickname for the Harrier Jets. The air intake is on the underside of the aircraft and resembles that of a F-16 Fighting Falcon.

Features and performance
The Hydra is the most sophisticated aircraft in the GTA series, boasting a variety of equipment. One of its more prominent abilities is its VTOL (Vertical Take Off and Landing) capabilities, which allow it to hover, descend or ascend vertically like a helicopter, and travel horizontally like an airplane; these abilities are achieved by directing thrust from four jet outlets downwards or backward using specific directional controls (by pushing the right analog stick forward/back, or, on a PC, by holding down 2/8 on the number pad or Ins/Del, by default. Or, with the IOS version, snaps automatically forward at a moderate speed). Due to its excellent engine and maneuverability, the Hydra is the fastest and fail-deadly aircraft (and one of the fastest vehicles) in GTA San Andreas, with a fixed top speed of 200 kph, and one of the easiest to fly when the player learns the basics of fixed-wing flight. However, similar aircraft like the Rustler, are more agile. It is very complicated, one mistake can send plummeting towards the ground.

The Hydra is the most preferred aircraft for its speed, agility, and weapons which make it an excellent choice for nearly any purpose requiring an airplane. Its chief disadvantage comes not from the vehicle itself, but the game engine - high-speed flight can allow the plane to hit objects, such as trees, before they've become visible due to model/texture loading being slower than the plane itself (this process is also nick-named 'pop-in'). Another drawback is that there is no passenger or co-pilot seat, restricting it to only carry one person, making it unsuitable for several-man transport.

Unlike the Hunter in GTA Vice City and GTA San Andreas, Vigilante side-missions cannot be started or performed using the Hydra.

Combat
The Hydra is well-known for being one of the most performing in-game vehicles in combat, on par with the Hunter. The Hydra comes with three sets of weapons which are :
 * Countermeasures : When used, the Hydra will drop a white flare that has the ability to deviate upcoming heat-seeking missiles. It can be noticed however that deviating will not put the Hydra in safe situation, as sometimes the missile may deviate for a few seconds before heading towards the jet again. Countermeasures then, if deployed at the right time, can buy some time for the pilot to escape a missile or definitely deviate a missile, either redirecting it upward or downward. Countermeasures affect missiles fired from the Area 69 SAM sites, other Hydras or from a Heat-Seeking Rocket Launcher, however it will not deviate rockets fired from a Rocket Launcher.
 * Missiles : When used, the Hydra will fire one unguided rocket per side. Despite unguided, if correctly aimed (deadly when used with the downward thrusts), it will make short work of vehicles, blowing them up on contact (except for the Rhino). The missiles, if they do not hit anything, will travel on a relatively long distance before blowing up.
 * Heat-seeking missiles : This alternative fire mode of the Missiles is identical to the handheld Heat-Seeking Rocket Launcher. The Hydra can lock on vehicles, and once it is done, when a missile is fired, it will be heat-seeking and will head towards the target. It is however less powerful that the unguided missiles (requiring three missiles to destroy a car instead of a single rocket for the unguided missiles). When fired towards an aircraft, it will be much faster, and is likely to reach its target.

Trivia

 * Once the player attains a 4 star wanted level or higher and is in the air, two Hydras will pursue and try to shoot down the player. The enemy Hydras should be no match, as they have a penchant for flying in lazy circles and not deploying flares, and as a result they will easily crash into buildings when flying in cities.
 * [[Image:DMAHydra.jpg|thumb|190px|The lettering on the rear fuselage.]]Part of the text on the side of the aircraft features the letters "DMA", this is likely a reference to Rockstar North, since the company was formerly known as DMA Design. DMA is also a play on United States Marine Corps squadrons that use the AV-8B Harrier II (VMA).
 * The Hydra is named after a Greek mythological beast, a 9 headed serpent-like creature that lived in Lake Lerna on the Pelopennese Island in Greece. Other vehicles named after mythological creatures include the Leviathan, Phoenix and Banshee.
 * The Hydra has a U.S. Airforce logo on it's left wing, but on the right wing, it does not.
 * The Hydra has a handling similar to that of a helicopter if the thrusters are not faced backwards.
 * An alternative model of the aircraft can be seen on one of Zero's hobby shop kits, sporting a V-tail and a more Harrier-esque look.
 * Hydra model kit.jpg all other planes in the game, the Hydra will cease to accelerate once it reaches 300 km/h. However, several trainers (such as the SCM hook) can disable the cessation.
 * The NPC Hydras chasing CJ in a dogfight are actually piloted by police officers from the city/region that they spawned from.
 * The GTA V equivalent of the Hydra is the P-996 Lazer. Also an AI controlled P-996 Lazer can launch flares but a player controlled Lazer cannot.
 * If you enter the Hydra with the landing gears retracted, upon entering the plane, the Hydra will explode.

GTA San Andreas

 * Easter Basin Naval Station: Available on the aircraft carrier after completing Vertical Bird, the player instantly gains a 5-star wanted level upon entry of the base, then stealing will cause the player to be chased down by NPC Hydras.
 * Verdant Meadows: In the hangar furthest away from the Abandoned AC Tower after the mission Vertical Bird.
 * Ganton: On Sweet's House rooftop after attaining 100% completion.
 * Area 69: Two spawn by a tank garage after Vertical Bird (dangerous to obtain, even if you use the 'lock wanted level' cheat code at zero stars; SAM Sites are still dangerous!).
 * 2 NPC Hydras pursue the player when in the air after reaching a 4-star wanted level; although it's extremely difficult as the wreck is likely to disappear and you are likely to get Busted, you can attain 6-star wanted level, shoot down one of them with a Rustler or Hunter, theoretically even a Sea Sparrow, as close as possible to Verdant Meadows (this is the easy part), land and bail out next to the wreck, jack a nearby Rhino and use it to push the wreck into your hangar.
 * The Hydra can be attained with the cheat code "jumpjet" for PC. For other consoles, see Cheats in GTA San Andreas.

GTA V
The Hydra was originally going to be in Grand Theft Auto V but was replaced by the P-996 LAZER for unknown reasons.

Glitches

 * There is a glitch that occasionally occurs with the flares; at times they do not deploy. You would then have to rely on the Hydra's evasiveness in order to avoid incoming missiles (hint: if you are flying at a high enough altitude, you can roll your Hydra upside down, then pull up. You will almost certainly evade the missile. If it is too high to dive, then use the rudder and turn at the same time.)
 * If you go to the Mount Chiliad (where a Mountain Bike appears) with the Hydra, if you start to lock-on over it and fire the missiles, oddly the Hydra receives damage until explodes like if you are attacked. This is due to the fact that bicycles aren't mean to explode and it will glitch the damage values, like a "bouncing" damage that affects the Hydra. (PS2 Confirmed)

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