Successfully complete the indicated task to unlock the corresponding character:

Dante: Successfully complete the game after making evil choices.
Isaac Clarke: Successfully complete the game after making good choices.
Jonah: Successfully complete the game.
Smiley: Successfully complete the game.

Play the mission where you are with the Russian that offers you money to leave him alone with the girl. Accept the $65,000 he offers, then exit to the main menu. Resume the game, and he will offer the money again. Repeat this as many times as desired to get an unlimited amount of money.

Successfully complete Stage 05 or 06 before Stage 04 to unlock Stage 03B: Captive City.

Successfully complete Stages 07, 09, 11, and 07C in that order to unlock Stage 07C: Time Limit.

Successfully complete Stages 07, 08, 10, 09, and 12C in that order to unlock Stage 12C: Wild Card.

Successfully complete SP Stage: Operation X to unlock the ADF-01 Falken.

Successfully complete Campaign mode on the Ace difficulty setting to unlock the Fenrir.

Successfully complete Mission 03B to unlock the XFA-27.

Successfully complete Campaign mode on the Hard difficulty setting to unlock the Ace difficulty setting.

Successfully complete the indicated task to be awarded the corresponding medal:

Bronze Ace: Destroy 200 enemies
Expert Marksman: Destroy 50 aircraft with guns
Eye of the Storm: Defeat the Gleipnir
Freedom Tower: Liberate Griswall
Gold Ace: Destroy 1,000 enemies
Land Guardian: Keep allied casualties at Stand Canyon to a minimum
Mark of the Vioarr: Defeat the Fefnir
Marksman: Destroy 5 aircraft with guns
Sea Guardian: Keep damage to the allied fleet at Terminus Island to a minimum
Sharpshooter: Destroy 15 aircraft with guns
Silver Ace: Destroy 500 enemies

Place first on all high score boards for all stages in a world to unlock bonus stages for that world.

Get 20 Specter Emblems to unlock the Specter Boxing mini-game.

Successfully complete the Specter Boxing mini-game to unlock the Specter Boxing mini-game bonus characters.

Successfully complete the Specter Boxing mini-game to unlock the Specter Boxing survival mode.

Get 30 Specter Emblems to unlock the Jake Attacks mini-game.

Get 40 Specter Emblems to unlock the Ape Ping-Pong mini-game.

Successfully complete the Ape Ping-Pong mini-game to unlock the Ape Ping-Pong mini-game bonus characters.

Successfully complete all missions on the Hard difficulty to unlock SP1 mission. Successfully complete all missions on the Ace difficulty to unlock SP2 mission.

Successfully complete the indicated task to unlock the corresponding aircraft:

FALKEN: Successfully complete Mission SP 02.
FENRIR: Successfully complete Mission 21A in Ace mode.
Varcolac: Successfully complete Mission 21A with an "S" rank in Ace mode.
X-02: Successfully complete Mission SP 01.

Successfully complete the indicated task to unlock the corresponding part:

Armor

Adv. Titanium Armor: Destroy the Ace named "Nightowl" in Mission 15 on the Hard difficulty (second playthrough) or Flight Time achievement 08:20.
Anti-Ground Armor: Destroy the Ace named "Offside" in Mission 12A on the Hard difficulty (second playthrough).
Beatle Armor: Destroy the Ace named "Balalaika" in Mission 5A or "Jolly" in Mission 5B.
Ceramic Armor: Destroy the Ace named "Gizmo" in Mission 9.
CFRP Conversion: Destroy the Ace named "Bloodstone" in Mission 14.
Composite Armor: Destroy the Ace named "Kelpie" in Mission 19 on the Hard difficulty (second playthrough).
DA Armor: Destroy the Ace named "Vulcan" in Mission 21A on the Ace difficulty.
Diffusion Coat: Destroy the Ace named "Hayate" in Mission 17 on the Ace difficulty.
Extra Hardpoint: Destroy the Ace named "Hengel" in Mission 8 on the Ace difficulty or "Jolly" in Mission 5B on the Ace difficulty.
Light Armor: Destroy the Ace named "Zircon" in Mission 7 on the Hard difficulty (second playthrough).
NERA Armor: Destroy the Ace named "Element" in Mission 16.
RAM Coat: Destroy the Ace named "Katana" in Mission 2 on the Hard difficulty (second playthrough).
Scale Armor: Destroy the Ace named "Kraken" in Mission 11.
TiAl Armor: Destroy the Ace named "Buzzard" in Mission 10 on the Ace difficulty.
Titanium Armor: Destroy the Ace named "Onyx" in Mission 4 on the Hard difficulty (second playthrough).

Avionics

AAM Jammer: Destroy the Ace named "Hayate" in Mission 17.
Ace's Amulet: Destroy the Ace named "Vulcan" in Mission 21A on the Hard difficulty (second playthrough) or "Garnet" in Mission 21B.
Adv. FCS: Destroy the Ace named "Sphinx" in Mission 6 on the Ace difficulty.
Adv. SA Radar: Destroy the Ace named "Katana" in Mission 2 on the Ace difficulty or "Mr. 8" in Mission 12B.
AMFD: Destroy the Ace named "Watercress" in Mission 1 on the Ace difficulty.
Argus: Destroy the Ace named "Element" in Mission 16 on the Ace difficulty.
Earth Shaker: Destroy the Ace named "Bloodstone" in Mission 14 on the Ace difficulty.
Emergency APS: Destroy the Ace named "Hengel" in Mission 8.
Fenrir ECMS: Destroy the Ace named "Kraken" in Mission 11 on the Ace difficulty.
GAF-1 Type AA: Destroy the Ace named "Lily" in Mission 20 on the Ace difficulty.
GAF-1 Type AS: Destroy the Ace named "Nightowl" in Mission 15 on the Ace difficulty or Flight Time achievement 10:00.
GAF-1 Type HS: Destroy the Ace named "Kelpie" in Mission 19 on the Ace difficulty.
Hawk Eye: Destroy the Ace named "Osaka" in Mission 3 on the Hard difficulty (second playthrough).
Raven: Destroy the Ace named "Balalaika" in Mission 5A or "Jolly" in Mission 5B.
Salamander: Destroy the Ace named "Kelpie" in Mission 19.
Sniper OS: Destroy the Ace named "Offside" in Mission 12A on the Ace difficulty or "Mr. 8" in Mission 12B on the Hard difficulty (second playthrough).
Terra Hammer: Destroy the Ace named "Zircon" in Mission 7.
Tracer: Destroy the Ace named "Balalaika" in Mission 5A on the Hard difficulty (second playthrough).

Engine

Adv. Turbo Engine: Destroy the Ace named "Offside" in Mission 12A.
Bullet Engine: Destroy the Ace named "Bloodstone" in Mission 14 on the Hard difficulty (second playthrough).
C-Cycle Engine: Destroy the Ace named "Lily" in Mission 20 on the Hard difficulty (second playthrough).
Caudal Engine: Destroy the Ace named "Buzzard" in Mission 10 on the Hard difficulty (second playthrough).
Hayabusa Engine: Destroy the Ace named "Hengel" in Mission 8 on the Hard difficulty (second playthrough).
Hydra Engine: Destroy the Ace named "Dandelion" in Mission SP1.
Light Engine: Destroy the Ace named "Nightowl" in Mission 15 or Flight Time achievement 06:40.
Mercury Engine: Destroy the Ace named "Zircon" in Mission 7 on the Ace difficulty.
Minotaur Engine: Destroy the Ace named "Express" in Mission 18.
RAMJet Engine: Destroy the Ace named "Element" in Mission 16 on the Hard difficulty (second playthrough).
Rocket Motor MOD Engine: Destroy the Ace named "Lily" in Mission 20.
SCRAMJet Engine: Destroy the Ace named "Timeline" in Mission 13 on the Hard difficulty (second playthrough).
Turbo Engine: Destroy the Ace named "Sphinx" in Mission 6.
Turbo RAMJet Engine: Destroy the Ace named "Kraken" in Mission 11 on the Hard difficulty (second playthrough).
Uranus Engine: Destroy the Ace named "Gizmo" in Mission 9 on the Ace difficulty.

Wing

Adv. A-Balance Tab: Destroy the Ace named "Timeline" in Mission 13.
Adv. Actuator: Destroy the Ace named "Osaka" in Mission 3 on the Ace difficulty.
Adv. B. Wing Body: Destroy the Ace named "Balalaika" in Mission 5A on the Ace difficulty.
Adv. Balance Tab: Destroy the Ace named "Gizmo" in Mission 9 on the Hard difficulty (second playthrough).
Adv. Sweep Wing: Destroy the Ace named "Hayate" in Mission 17 on the Hard difficulty (second playthrough).
Adv. Trimtab: Destroy the Ace named "Buzzard" in Mission 10.
Air Gripper: Destroy the Ace named "Balalaika" in Mission 5A or "Jolly" in Mission 5B.
Extra Airbrake: Destroy the Ace named "Balalaika" in Mission 5A or "Jolly" in Mission 5B.
Extra Canard: Destroy the Ace named "Sphinx" in Mission 6 on the Hard difficulty (second playthrough).
Extra Elron: Destroy the Ace named "Vulcan" in Mission 21A.
Extra Hardpoint: Destroy the Ace named "Timeline" in Mission 13 on the Ace difficulty or "Garnet" in Mission 21B.
Extra Ladder: Destroy the Ace named "Balalaika" in Mission 5A or "Jolly" in Mission 5B.
Extra V Canard: Destroy the Ace named "Express" in Mission 18 on the Hard difficulty (second playthrough).
Sylph Wing: Destroy the Ace named "Strigon", "Gryphus1", "Garm1", "Wardog", "Zipang", "Yellow 13", "Mobius1", "Dision", "Z.O.E", and "Phoenix" in Mission SP2.
Thornback Fin: Destroy the Ace named "Watercress" in Mission 1 on the Hard difficulty (second playthrough).

Reach 100 sorties to unlock Mobius1's emblem.

Successfully complete the indicated task to unlock the corresponding medal:

Armament Specialist: Unlock all aircrafts, colors, weapons, parts, and emblems.
Bronze the Ace: Destroy 200 enemies.
Bronze Medal of Excellence: Get an "S" rank in all missions on the Normal difficulty.
Conqueror: Successfully complete Campaign mode with the longest path (18 missions).
Expert Marksman: Destroy 50 enemies with the machine gun.
Ghost Hunter: Destroy 20 Spiridus or Orgoi.
Gold the Ace: Destroy 1,000 enemies.
Gold Medal of Excellence: Get an "S" rank in all missions on the Ace difficulty.
Guardian of London: Get an "S" rank in mission 12A/12B on the Normal or higher difficulty.
Guardian of San Fransisco: Get an "S" rank in mission 21A/21B on the Normal or higher difficulty.
Guardian of Tokyo: Get an "S" rank in mission 5A/5B on the Normal or higher difficulty.
Legendary Wings: Win 20 missions with A6M5 Zero or F6F-5 Hellcat.
Marksman: Destroy five enemies with the machine gun.
Sharpshooter: Destroy 15 enemies with the machine gun.
Silver the Ace: Destroy 500 enemies.
Silver Medal of Excellence: Get an "S" rank in all missions on the Hard difficulty.
Swift Hunter: Successfully complete Campaign mode with the shortest path (16 missions).
Wolf Hunter: Shoot down 50 Varcolacs.

Pause the game and press Up, Down(2), Up, L, R.

Pause the game and press Left(2), R, Down(2), L.

Pause the game and press R(2), L, R, Left, Up.

Pause the game and press Left, L, Right, L, Up, Down.

Pause the game and press L(2), R(2), L, Left.

Pause the game and press R, Up, L, Up, Down, R.

Use the Gale attack. Hit him with the gale, then run. Repeat the hit and run strategy until he has been defeated.

At the title screen or while playing the game, hold L and press Up, Down, Left, Right, Square.

At the title screen or while playing the game, hold L and press Up, Down, Left, Right, Triangle.