Interesting CH-47 Chinook facts

• Its top speed of 170 knots (196 mph, 315 km/h) was faster than contemporary utility and attack helicopters of the 1960s and even new helicopters such as Apache and Blackhawk. Its high altitude perfomance is better than the Blackhawk over Afghanistan.
• It is one of the few aircraft of the 1950s/60s such as the C-130 and the Bell Huey family that is still in production and front line service with over 1,179 built so far
• It's not as big as the Russian Mil Mi-26, which has been contracted by the US to recover crashed CH-47s in Afghanistan. but it's the largest lifter in the US Army.
• Jet-engine derived turboshaft engines were the key to performance advantages over previous piston powered helicopters. The first models had twin 2,200 horsepower engines. The versions just ordered by Canada will have two 4,733 horsepower Honeywell engines
• The counter-rotating rotors eliminate the need for an anti-torque vertical rotor, allowing all power to be used for lift and thrust. The ability to adjust lift in either rotor makes it less sensitive to changes in the center of gravity, important for the cargo lifting role. If one engine fails, the other can drive both rotors.[7], but the cross shafting transmission adds expense and complexity compared to a small tail rotor.