Operation Modern was a seldom reported deal between Indonesia and United States for the exchange of four MiG-21F-13 fighters for 19 T-33 trainers.
Museum Pusat TNI AU Dirgantara Mandala Yogyakarta, CC BY-SA 4.0, via Wikimedia Commons
A total of 13 MiG-21s went to America in exchange for the T-33, UH-34D, and later, F-5 and OV-10 aircraft.
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