6 large planes from Neuwork's air force are en route to General Resource's White Valley Air Base at an altitude of 30,000 feet. Use the high altitude stratofighter RF-12A2 "Blackbird" to attack the hostiles.
Earning an A-Rank requires destroying 8+ enemies.
You prevented an attack by Neuwork on General Resource's air base. Your combat performance under difficult high altitude conditions was exemplary!
Even though the briefing states that there are 8 R-311s, there are only 7 R-311s.