ENGINE TAKEOFF". The Skymaster's unique sound is made by its rear pusher propeller slicing through turbulent air from the front propeller and over the airframe while its front tractor propeller addresses undisturbed air. Operational history From 1976 until the middle 1990s, the California Department of Forestry and Fire Protection used O-2 variants of the 337 Skymaster as tactical aircraft during firefighting operations. These were replaced with North American OV-10 Broncos, starting in 1993. Brothers to the Rescue From 1991 until 2001 the Cuban exile group Hermanos al Rescate (Brothers to the Rescue) used Skymasters, among other aircraft, to fly search and rescue missions over the Florida Straits looking for rafters attempting to cross the straits to defect from Cuba, and when they found them, dropped life-saving supplies to them. Rescues were coordinated with the US Coast Guard, which worked closely with the group. They chose Skymasters because their high wing offered better visibility of the waters below, they were reliable and easy to fly for long-duration missions (averaging 7 hours), and they added a margin of safety with twin-engine centerline thrust. In 1996, two of the Brothers to the Rescue Skymasters were shot down by the Cuban Air Force over international waters. Both aircraft were downed by a MiG-29, while a second jet fighter, a MiG-23, orbited nearby. Variants Cessna 327 Baby Skymaster - reduced scale four-seat version of the 337, with cantilever wings replacing the 336/337 strut-braced configuration. It first flew in December 1967. One prototype was built before the project was cancelled in 1968 due to lack of commercial interest in the design. The prototype was delivered to NASA to serve as a full-scale model for wind tunnel testing. It was used in a joint Langley Research Center and Cessna project on noise reduction and the use of ducted versus free propellers. 336 Skymaster - production version powered by two Continental IO-360-A engines, 195 built. 337 Super Skymaster - 336; retractable undercarriage, redesigned nose cowling and new rear engine intake, and greater wing angle of incidence, powered by two Continental IO-360-C engines, 239 built. - 337; minor detail changes, 255 built. - 337A; increased take-off gross weight, optional belly cargo pack, 230 built. T337B (1967) Turbo Super Skymaster - 337B; two Continental turbocharged fuel injected engines which boosted service ceiling to , cruise speed to , and range to - 337B; new instrument panel and increased take-off gross-weight,