The 156th Tactical Fighter Wing "Aquila", more popularly known and referred to as "Yellow Squadron", was an elite squadron of the Federal Erusea Air Force (FEAF). The squadron's primary role was the defense of Stonehenge during the Second Usean Continental War.
In the years leading up to and during the war, Yellow Squadron became notorious among the Independent State Allied Forces for its members' extraordinary combat skills. For the first half of the war, ISAF engagements with Yellow Squadron were strictly prohibited. ISAF's ace, Mobius 1, would later engage the Yellows over Stonehenge and the Erusian capital, Farbanti, leading to the squadron's disbandment after all of its members were killed in action during Operation Autumn Thunder.
Yellow Squadron is believed to have existed prior to the continental war, but any records of the squadron's previous engagements are unknown. At some point, Yellow 13 was promoted to the role of flight leader, with Yellow 4 as his permanent wingman; the other squadron members were regularly rotated out by FEAF command to reinforce other squadrons and boost troop morale.
Early defense of Stonehenge
In the late 1990s and early 2000s, development of the FEAF's X-02 Wyvern project was well underway. Upon Erusea's capture of Stonehenge in 2003, the Erusian High Command ordered the production of several X-02 units for the purpose of defending Stonehenge. This plan was met with heavy opposition from certain groups, including the Erusian Parliament, which argued that more conventional aircraft would be better suited to the task rather than an experimental one. The X-02s become tangled in bureaucratic debate and were not completed until after the war's end; Yellow Squadron would consequently become the primary protectors of the STN facility flying Su-37 Terminators with camouflage livery.
At some point in early 2004, during the Allies' retreat across the Usean mainland, ISAF deployed several squadrons to attempt an assault on Stonehenge. Before any of the aircraft could reach the operational zone, however, Yellow Squadron engaged and shot down all of the ISAF pilots. ISAF declared the mission a complete failure and was ultimately forced to continue its retreat to North Point. Following the ISAF's evacuation from the mainland, the need for Yellow Squadron waned as the frontlines shifted to the far eastern coast of Usea, effectively putting Stonehenge out of range from further ISAF airstrikes.
- "Tally ho on the bogeys! There's five Yellows."
- ― ISAF pilot
Following the success of Erusea's continent-wide offensive, Yellow Squadron was assigned to several long-range missions from its newly acquired runway and makeshift airbase in San Salvacion. When the ISAF launched an attack against the Aegir Fleet's refueling facilities outside of Comberth Harbor, Yellow Squadron was deployed to intercept the ISAF fighters. Although they failed to prevent the attack, Yellow Squadron was able to splash multiple ISAF aircraft, forcing them to withdraw from the combat zone. 
Less than a month later, ISAF attempted to launch a new reconnaissance satellite from Riass Space Center in the Comona Islands. A massive aerial engagement soon broke out over the launch site. Yellow Squadron was among the numerous Erusian air forces attempting to halt the launch; however, the Yellows collectively retreated after Mobius 1 damaged one of their wingmen.
Death of Yellow 4
As the war progressed, the ISAF began counteroffensive operations to regain lost territory and eventually ordered a second assault on Stonehenge. Before the air raid commenced, however, a member of the San Salvacion resistance detonated a bomb on Yellow Squadron's runway; the explosion inflicted light shrapnel wounds to Yellow 4 and damaged one of her Su-37 Terminator's engines. Whether or not this incident was a coordinated effort between the resistance and ISAF is unknown. Regardless, the bombing helped delay Yellow Squadron's response when the call to defend Stonehenge was made.
Similar to the raid on the petrochemical complex several months earlier, Yellow Squadron failed to arrive in time to prevent the STN's destruction but proceeded to engage the ISAF pilots nevertheless. Mobius 1 engaged the Erusian aces and managed to shoot down Yellow 4. After confirming she had failed to eject, Yellow Squadron retreated from the airspace.
End of the war
Following Yellow 4's death, FEAF command continued to cycle new pilots through Yellow Squadron's roster in hopes of bolstering their ranks and strengthening the squadron in preparation for ISAF's push into the mainland. By July 2005, ISAF forces had reached Erusian-occupied San Salvacion and began an operation to liberate the city. Yellow Squadron was deployed around the city's airspace, but the battle eventually turned in ISAF's favor, and the Erusian forces retreated once more.
By fall of 2005, the ISAF forces had broken through the Erusians' Whiskey Corridor defense line and arrived at the outskirts of Farbanti. The ensuing battle ultimately ended with ISAF ground troops capturing the Erusian General Headquarters while Erusea's military leaders—including the Supreme Commander—attempted to escape via helicopters. The remaining members of Yellow Squadron, including Yellow 13, scrambled to defend the helicopters and shoot down ISAF's ace, Mobius 1. In the ensuing dogfight, Mobius 1 shot down and killed all five Yellow pilots. It is believed that the squadron was officially disbanded as part of Erusea's disarmament, in accordance with the terms of the peace accords.
Megalith defense squadron
Main article: Megalith defense squadron
Despite the war's official end on September 19, 2005, a splinter group of Erusian officers refused to accept the ceasefire's terms and took control of Megalith, a rocket-launch facility capable of turning asteroid fragments into weapons of mass destruction. ISAF quickly organized the new Mobius Squadron—comprised of Mobius 1 and other veteran ISAF pilots—to perform a joint ground-air operation to destroy Megalith.
In response, the Erusian rebels rallied a new squadron to defend the facility, led by Jean-Louis Flaubert and his second-in-command, Gene. The squadron was comprised of 15 pilots, each flying Su-37 Terminators with the same livery as Yellow Squadron. The defense force was also named "Yellow Squadron" out of respect for the aces lost during the Siege of Farbanti one week prior. However, the defending pilots did not possess the skills or training of their squadron's namesake and were shot down in the ensuing dogfight; Megalith was subsequently destroyed as well. This defeat marked the end of Yellow Squadron's legacy.
Main article: Yellow 13
Yellow 13 was the flight leader of Yellow Squadron throughout its known tenure. He was considered to be the best fighter pilot in the Federal Erusea Air Force, but his true source of pride came from his record of never losing a squadmate in combat. He also held contempt for those who would sabotage pilots while on the ground. Although he did not freely discuss shooting down his enemies, Yellow 13 was otherwise affable and came to support San Salvacion civilians, such as the Side Story Narrator, during the country's occupation. However, he became more focused on his missions and the safety of his squadron following the loss of Yellow 4. In the wake of her death, Yellow 13's demeanor became more somber and serious. Like the rest of Yellow Squadron, he was killed in action over Farbanti by Mobius 1 on September 19, 2005.
Main article: Yellow 4
Yellow 4 was Yellow 13's primary wingman and the only known female pilot in Yellow Squadron. She and Yellow 13 had known one another before enlisting in the Erusian air force and had developed a strong, possibly romantic, bond. Yellow 4, despite her outwardly gentle disposition, would not let any harm befall Yellow 13 either in the air or on the ground—she loyally remained by his side at nearly all times to protect him. Yellow 4 was injured and her aircraft was damaged when an explosive planted by the San Salvacion resistance detonated on their runway. Regardless, she sortied with the rest of her squadron to defend against ISAF's second raid on Stonehenge. However, the damage to her aircraft proved too extensive, and she was shot down by Mobius 1 on April 2, 2005.
- Yellow Squadron's paint scheme is the most recurring livery in the Ace Combat series; it appears in a total of nine games (including AC04).
- The squadron's name and the design at the bottom of its emblem are derived from the constellation Aquila, which translates to "eagle" in Latin.
- The Yellow Squadron was conceived by cutscene director Sunao Katabuchi. He cited his conception of the squadron as what led to the idea for Mobius 1, the player's ace and the Yellows' greatest rival.
- Early drafts of the squadron's signature camouflage livery were conceived by Kazutoki Kono, who originally depicted the Yellows using Su-30MKIs bearing a livery inspired by the Su-27PD technology demonstrator, which has been available as an unlockable paint scheme for Flanker-class aircraft in several games from Ace Combat 04: Shattered Skies onward.
- According to Kono, the American staff had plans to change the squadron's name to "Gold Squadron" believing that Yellow sounded too "weak". However, the development team insisted on keeping "Yellow Squadron", and the name pressed through to the game's release.
- Erich Klinsmann, an ace from the Belkan Air Force, flew an Su-37 Terminator with the same livery later used on Yellow Squadron's Terminators. No detailed information on Klinsmann is available, leading some fans to theorize that he and Yellow 13 are the same pilot.
- An unknown pilot under the callsign "YELLOW" was shot down during the Circum-Pacific War inside the Gründer Industries' tunnel beneath Sudentor, Belka. His aircraft features the same livery as Yellow Squadron's and the number 13—no other information about him is known. This has led to speculation that Yellow 13 could have survived the Siege of Farbanti and later joined the Belkan Air Force.
- Yellow Squadron is one of the few squadrons featured in Strangereal that can regularly perform the Pugachev's Cobra maneuver.
- Following the release of Ace Combat 04, some fans reported that they were able to either hit or shoot down a Yellow during Lifeline, widely believed to be impossible. The game's director, Hiroyuki Ichiyanagi, expressed his surprise upon reading such claims, realizing that they hadn't made the Yellows as invincible as they had hoped.
- Despite the fact that the artwork for Yellow Squadron's Su-37s depicts the aircraft as armed with XMAAs, the plane cannot be armed with them in the game, neither by opponents nor by the player.
- The Usean Rebel Forces operate Su-37s with a palette-swapped version of Yellow Squadron's livery. Additionally, one of the rebel aces, Ricochet, uses another palette-swapped variation.
- According to cut in-game dialogue, Yellow Squadron originally had unique voices and phrases, unlike in the final version where they use basic enemy pilot lines. Included is the indication Yellow Four was originally intended to be a male pilot.
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Siege of Farbanti, Ace Combat 04: Shattered Skies.
- ↑ 2.0 2.1 Ace Combat 04: Shattered Skies.
- ↑ 3.0 3.1 Lifeline, Ace Combat 04: Shattered Skies.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Interlude 06, Ace Combat 04: Shattered Skies.
- ↑ Interlude 01, Ace Combat 04: Shattered Skies.
- ↑ "Withdrawal from the Usean Continent", AC04Web. Published 2001.
- ↑ Cutscene during Lifeline, Ace Combat 04: Shattered Skies.
- ↑ 8.0 8.1 Shattered Skies, Ace Combat 04: Shattered Skies.
- ↑ 9.0 9.1 9.2 Interlude 07, Ace Combat 04: Shattered Skies.
- ↑ 10.0 10.1 Stonehenge Offensive, Ace Combat 04: Shattered Skies.
- ↑ 11.0 11.1 11.2 Interlude 08, Ace Combat 04: Shattered Skies.
- ↑ Interlude 09, Ace Combat 04: Shattered Skies.
- ↑ Emancipation, Ace Combat 04: Shattered Skies.
- ↑ Interlude 10, Ace Combat 04: Shattered Skies.
- ↑ Interlude 11, Ace Combat 04: Shattered Skies.
- ↑ 16.0 16.1 Megalith, Ace Combat 04: Shattered Skies.
- ↑ Ace Combat: Assault Horizon DLC.
- ↑ Interlude 03, Ace Combat 04: Shattered Skies.
- ↑ Interlude 06, Ace Combat 04: Shattered Skies.
- ↑ Reddit AMA / Sunao Katabuchi. Published February 27, 2014. Retrieved December 17, 2014.
- ↑ Twitter / ACE COMBAT. Published September 26, 2014. Retrieved December 17, 2014.
- ↑ Twitter / Kazutoki Kono. Published May 28, 2015.
- ↑ Ace Combat Zero: The Belkan War.
- ↑ ACES, Ace Combat 5: The Unsung War.
- ↑ Ace Combat 6: Fires of Liberation: Page 4. GamesRadar+. Published on April 4, 2007. Retrieved on December 15, 2016.
- ↑ Ace Combat 2.