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 Regional Hospital Chinook Regional Hospital Chinook Regional Hospital is the main hospital for the City of Lethbridge and Southern Alberta, and offers many of the health care services for Alberta Health Services. The hospital services a population of over 150,000 and is supported by the Chinook Regional Hospital Foundation. The first hospital in Lethbridge opened in 1891 by the family of Alexander Galt, a local entrepreneur. The original building now houses the Galt Museum. The Sisters of St. Martha opened the St. Michael's Hospital at 13th Street South and 9th Avenue South in 1929. In 1955, the City of Lethbridge built a