-collective variation = intensity
-cyclic variation = direction
The CH-47 Chinook is a heavy maneuver and assault helicopter manufactured by Boeing. Its two tandem rotors (set of horizontal rotors mounted one in front of the other) are counter-rotating and are controlled synchronously in stationary and in translation, thus their torque effect is canceled out by their opposite direction of rotation. It is equipped with two turboshaft engines with a power of 2,850 hp to 3,750 hp,(help to moving forward) with a maximum weight of 18.5 tonnes.
Photo below we see that the rear rotor is raised relative to the front rotor.
an asymmetry of the lift between the 2 rotors implies a tilting along
its pitch axis and causes the device in forward flight.the tandem
rotors are very bulky and not very maneuverable, which constitutes
their main defect. Note also that the lengthening of the fuselage
makes them more sensitive to strong wind
So it's mostly like an helicopter with one rotor( cyclic variation to move forward) but a few different.your hypothesis is not really right because the two rotor are connected and
are controlled synchronously in stationary and in translation(same speed)
The main MGB gearbox is interconnected with the shafts of the two turbine engines. A seven-section shaft connects the main gearbox to the front gearbox, and a two-section shaft connects the main gearbox to the rear gearbox. The oil cooling fan is driven by the rear gearbox.
Longitudinal control of tandem rotor helicopters is accomplished by differential thrust of the forward and aft rotors creating pitch attitude changes of the fuselage about its lateral axis.
Lateral control is accomplished by the lateral tilt of both rotor discs, which causes the fuselage to roll about its longitudinal axis
Directional control is accomplished by differential lateral tilting of both rotor discs, which causes the aircraft to turn about its vertical axis.