Boeing engine started in 1943 and Boeing's gas turbines were designated models 502 (T50), 520 (T60), 540, 551 and 553. Boeing built 2,461 engines before production ceased in April 1968. Many applications of the Boeing gas turbine engines were considered to be firsts, including the first turbine-powered helicopter and boat. Vertol Aircraft Corporation was acquired by Boeing in 1960, and was reorganized as Boeing's Vertol division. The twin-rotor CH-47 Chinook, produced by Vertol, took its first flight in 1961. This heavy-lift helicopter remains a work-horse vehicle to the present day. In 1964, Vertol also began production of the CH-46 Sea Knight.
Mil Moscow Helicopter Plant Series production facilities for Mil-designed helicopters include Rostvertol in Rostov-na-Donu, the Kazan Helicopter Production Association, and the Ulan-Ude Aviation Plant. Mil participates in the Euromil joint venture with Eurocopter. Mil was established in 1947 under the guidance of Mikhail Mil as the helicopter laboratory of the Central Aerohydrodynamic Institute in Zhukovsky, Moscow Oblast. The Mil Mi-1 became the first mass-produced Soviet helicopter. The Mi-8 helicopter, designed in the early 1960s, was a successful design in both military and civil applications, with over 12,000 units being produced. Mil merged with Kamov and Rostvertol to form Russian Helicopters in 2006. The Mil