Pima Air & Space Museum. From left to right: Sikorsky HH-19B Chickasaw (52-7537), Sikorsky HO3S-1G (232), Sikorsky HH-3F Pelican (1476), Piasecki H-21B Shawnee (53-4389), Piasecki HUP-3 Retriever (147595), Sikorsky HH-52A Sea Guardian (1450).