There are 6 Hiller H-23D 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 1959 and 1972.
N33472
1972 Hiller H-23D
Mineral Wells, TX
N94517
1961 Hiller H-23D
Mineral Wells, TX
N48263
1959 Hiller H-23D
Merritt Island, FL
N94516
1959 Hiller H-23D
Mineral Wells, TX
N64275
Hiller H-23D
Tyler, TX
N67107
Hiller H-23D
Glendive, MT