After the United Forces entered Republic City's harbor, they were quickly ambushed by a large formation of Equalist biplanes that had been deployed from an airfield located in the mountains northwest of the city.
Later on, Team Avatar, along with the newly recruited General Iroh, pinpointed the airfield's location on a map of Republic City and its surrounding landscape. Iroh, Bolin, and Asami then decided that at dawn, they would to travel by polar bear dog to the airfield and stop any more aircraft from taking off.
The next day, as the group approached the airfield, Bolin instructed Naga and Pabu to stay behind and not to follow them into the base. As they approached the compound, they were electrocuted by an electric fence and brought to a prison cell in the base. After being visited by Hiroshi Sato, who told them that he was about to destroy Commander Bumi's fleet of battleships, Naga and Pabu broke into the airfield base and destroyed the iron bars to Iroh, Bolin, and Asami's prison cell. The group then proceeded to head outside toward the individual airstrips.
Once outside, General Iroh managed to commandeer a biplane that was about to take off, and went after the planes that were headed toward Commander Bumi's fleet of battleships. Meanwhile, Asami discovered a number of mecha tanks and biplanes in the airfield's hangar and seized control of one of the tanks, using it to destroy the airplanes in the hangar. Meanwhile, Bolin was outside using his earthbending to destroy the airstrips, effectively preventing any more airplanes from taking off. Back inside the hangar, however, as Asami was using her mecha tank to destroy more Equalist airplanes, she was approached by her father, operating a mecha tank of his own. After a brief fight, Hiroshi was about to deliver the final blow, but was stopped by Bolin, who launched an onslaught of earthbending attacks at him from Naga's back. Hiroshi was eventually captured and the airfield was effectively taken out of commission.
Hiroshi's airfield consisted of a large hangar for storing airplanes and mecha tanks, as well as at least one small prison cell and five individual airstrips. There were also three smaller buildings located behind the main hangar. The entire compound was surrounded by an invisible electric fence that would electrocute anything upon contact.