There are 3 Construcciones Aeronauticas Sa C.A.S.A. 1.131 aircraft on the U.S. registry that TailWiki has a page for. Every one is built from the public FAA record — year, serial, engine, home base, and registration history — and owners and pilots add photos, trips, and stories on top. The ones listed here were built between 1953 and 1962.
N131J
1962 Construcciones Aeronauticas Sa C.A.S.A. 1.131
Landenberg, PA
N1950M
1958 Construcciones Aeronauticas Sa C.A.S.A. 1.131
Wilmington, DE
N131SK
1953 Construcciones Aeronauticas Sa C.A.S.A. 1.131
Vineburg, CA