Cessna—A-37 Dragonfly: USAF Variants and Serials OA-37B: Following the withdrawal of the A-37B in the ground-attack role, the type was adapted to conduct forward air control duties to replace the O-2 Skymaster. · Over 100 A-37Bs were redesignated to OA-37B configuration, although very few remain in service. GOA-37B: Two retired OA-37Bs have been allocated to the Inter-American Air Forces Academy (IAAFA) as ground instruction airframes to teach technical skills to students from Central and Latin American countries. · 69-6375; 73-1098 NOA-37B: At least two OA-37Bs were allocated to permanent test duties with the Air Force Flight Test Center at Edwards AFB, with the prefix N assigned. · 70-1310; 73-1090