The CAP 20 is a single seat derivative of the CAP 10.
The CAP 20A is a single seat derivative of the CAP 10 with a no dihedral wing and lengthened landing gear.
The CAP 20B is a modified CAP 20A with new wings and larger ailerons.
The CAP 20L is a shorter airplane than its predecessor, the 20, and it seems to benefit from a much increased rudder area. Lightened for competition (hence the L designation, for leger), the CAP 20L also has a new wing design.
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