"We are planning a surprise attack to recapture our country's largest air base, the Sachana Air Base. The base, with its large supply warehouses, is a crucial strategic point as well as a vital supply channel. By securing Sachana Air Base, our forces will gain a necessary staging point for a combined allied assault on the capitol. At present, the Leasath Air Force is grounded, but they're mobilizing to aid ground forces fighting on the Kalana Steppes. The Skylla Unit is also rumored to be stationed at Sachana Air Base. They are an elite team highly skilled in anti-aircraft tactics. A head-on confrontation must be avoided at all costs. Therefore, we have devised a plan to penetrate deep into enemy territory and strike while their attention is still focused on the Kalana Steppes. A sweeping radar net lies between here and Sachana Air Base. However, by flying at an altitude of 1600 feet (300 meters), you should be able to make it through undetected. A sudden and precise strike on the base will greatly increase our chances of winning without risking a head-on confrontation."
Gryphus One is tasked with infiltrating the enemy radar network and neutralizing Sachana Air Base, leading the way for a combined allied assault on Griswall.
In order to remain hidden, Gryphus One must fly below a certain altitude (the altitude limit goes lower if playing on a higher difficulty), as well as to sink all of the patrol boats undetected in either one of two routes: the first, which is drectly in front of him, contains a number of turns heading northwest and another, located farther to the left, features a much straighter path.
If the boats in either route were sunk, the Mission Update will commence and Gryphus One is clear to engage the mission-critical targets. After destroying a few TGT-marked objects, the Skylla Unit will appear within the base's perimeter. They must also be eliminated to complete the mission.
The S-Rank is achieved when the mission is completed in a quick time, regardless of the score.
CH-47 - Spawns at the start of the mission to the west.
"The surprise attack was a success. Sachana Air Base is back in our hands. Air power from the base will be a vital asset, especially in the battle to retake Griswall. I have a feeling that the day of our capital's liberation is not far off."