Helicopter rotor of gravity fore-aft. However, it requires the expense of two large rotors rather than the more common one large main rotor and a much smaller tail rotor. The Boeing CH-47 Chinook is the most common tandem rotor helicopter. Coaxial rotors are a pair of rotors mounted one above the other on the same shaft and turning in opposite directions. The advantage of the coaxial rotor is that, in forward flight, the lift provided by the advancing halves of each rotor compensates for the retreating half of the other, eliminating one of the key effects of dissymmetry of lift: retreating blade
Chinook Jargon in British Columbia by gold prospectors and Royal Engineers. As industry developed, Chinook Jargon was often used by cannery workers and hop pickers of diverse ethnic background. Loggers, fishermen and ranchers incorporated it in their jargon. A heavily creolized form of Chinook Jargon (Chinuk Wawa) is still spoken as a first language by some residents of Oregon, much as the Métis language Michif is spoken in Canada. Hence, Chinuk Wawa as it is known in Oregon is now a creole language, distinct from the widespread and widely varied pronunciation of the Chinook Jargon as it spread beyond the Chinookan homeland.