The Hydra is evidently a jet-powered military aircraft, bearing (slightly modified) roundels of the United States Air Force on its wings. The Hydra is suggestively based on the McDonnell Douglas (now Boeing/BAe) AV-8B Harrier II. 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 Lockheed F-16.
In flight, with its thrusters directed to the back.
Parked, with its landing gear down and its thrusters directed downwards.
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 allows it to hover or descend or ascent vertically, like a helicopter, and travel horizontally like an airplane; these abilities are achieved by directing thrust from four jet outtakes downwards or backward using specific directional controls (by pushing the right analog stick forward/back, or, on a PC, by holding down 8 on the number pad, or Del). Due to its excellent engine and maneuverability, the Hydra is the fastest aircraft (and one of the fastest vehicles) in GTA San Andreas, with a fixed top speed of 300 km/h and one of the easiest to fly when the player learns the basics of fixed-wing flight.
The Hydra comes with various armaments, including lock-on or manual-aimed missiles, and flares as countermeasures for oncoming missiles fired by enemies, which redirects lock-on missiles shot from enemy Hydras or SAM sites (like those guarding Area 69) away from the player.
The Hydra is rated by many players as their favorite aircraft, for its speed, agility, and weapons which make it an excellent choice for 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, well before they've become visible due to model/texture loading being slower than the plane itself.
Unlike the Hunter in GTA Vice City and GTA San Andreas, Vigilante side-missions cannot be started or performed using the Hydra.
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.
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).
Like the Leviathan, 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.
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.
Like 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 this limit.
The Hydra might also make an appearance in the upcoming GTA V. In the trailer, you can see a Hydra-like plane flying over LS, it again strongly resembles a AV-8B Harrier II.
The NPC Hydras chasing CJ in a dogfight are actually piloted by police officers from the city/region that they spawned from.
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,
The Hydra can be attained with the cheat code "jumpjet".
The Hydra can be found in the police garage underneath the Las Venturas Police Headquarters, although it's incredibly difficult to fly it out of the garage, and usually results in the death of the player.
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Added by C-d-rom
