;Let.1 A.3 :initial reconnaissance version, powered by two
Hispano-Suiza 8A engines and having a three bay wing. ;Let.2 A.3 :reconnaissance aircraft similar to Let.1, but powered by two
Hispano-Suiza 8Ba engines and also having a three bay wing. ;Let.3 Bn.3 :night bomber, powered by two
Hispano-Suiza 8Ba engines and having a four bay wing. ;Let.4 A.3 :reconnaissance aircraft also used as a bomber, powered by two
Lorraine-Dietrich 8A engines and having a three bay wing. ;Let.5 A.3 :reconnaissance aircraft powered by two
Lorraine-Dietrich 8B engines, having a three bay wing and missing the nosewheel. ;Let.6 Ca.3 :fighter based on the Let.3, armed with a cannon, powered by two
Hispano-Suiza 8Be engines and fitted with a four bay wing. ;Let.7 Bn.3 :night bomber, powered by two
Lorraine-Dietrich 8B engines and fitted with a four bay wing of increased span. ==Operators==