produces 10 M28s per year. Sikorsky's current owner, Lockheed Martin, has marketed it to the governments of Indonesia, Jordan, Poland, Venezuela, Vietnam, the U.S. and commercial operators. Split equally between commercial and military applications, it competes with the Viking Air Twin Otter, the Let 410 and the Dornier 228. Design The M28 is a twin-engined high-wing strutted monoplane with an all-metal airframe, twin vertical fins and a tricycle fixed landing gear. If an engine fails, a spoiler forward of the aileron opens automatically on the opposite wing. This limits the wing drop to 12° in five seconds instead of 30°. It is capable of Short takeoff & landing (STOL) and hot and high altitude operations. Aerodynamically deployed leading edge slats when approaching stall speed enable a low stall speed and while the certification landing field is , PZL has demonstrated landing in . Inlet air ducts inertial separators and inverted configuration of the PT6 and the high wing configuration protect the engines and propellers against foreign object damage for unprepared runways operations. Multiple configurations are available: a 19-passenger airliner with 2-1 seating and an underbelly luggage pod; a cargo aircraft with a hand-cranked hoist option; the most common combi; a VIP transport; a medevac for six litters and seven seats; a search-and-rescue version; a 17-seat paratrooper drop version; an 18-passenger utility cabin and an aerial firefighting version is considered. A crew of two can switch between passenger and cargo configurations in 7 min. Its inward opening rear doors allow for cargo drops and utility operations as well as the passenger boarding. It can take off in at the MTOW. Maximum payload is , it can carry over or with full fuel over . Operational history 176 An-28s and M28s in all variants were built in Poland by 2006. Most numerous users are former Soviet civil aviation and the Polish Air Force and Navy (about 25 as of 2006), smaller numbers are used by the Polish civil aviation and in the United States, Nepal, Colombia, Venezuela, Vietnam and Indonesia. On 4 November 2005, a Vietnamese Airforce M28 crashed in Gia Lam district, Hanoi. All three crewmembers were killed. On 12 February 2009, The weekly periodical Air Force Times reported that the Air Force Special Operations Command (AFSOC) would receive 10 PZL M28 Skytrucks in June 2009. These aircraft carry the U.S. Air Force model design series (MDS) designation of C-145A Skytruck.