This is the last versión of the Observation model manufactured by the Fabrica Militar de Aviones. Similar to the Ae M Oe1 it had a larger vertical Surface and a squared rudder.
Modifications to the last helped to solved yaw problems. Fourteen units were manufactured for the Army in 1937. They were SOC in 1945 when the Air Force was born with the Ea-59 under evaluation until 1946.