Originally Posted by
stilton
Ok, understood then, correct me if i'm wrong but neither rotor can tilt forward and aft like a 'conventional' helicopter or it would risk having the blades hit each other ?
Interesting that isn't an issue with the rotors tilting left and right.
So when you input forward cyclic the desired affect is achieved by increasing the pitch on the rear rotor and decreasing on the front and vice versa on rearward cyclic ?
A unique result of such a dynamic is upon arriving in a high nose high attitude and gross weight approaching the limits of power.....as you try to lower the nose by applying forward cyclic...you are reducing lift in the forward head and demanding more from the aft head that might not be available.....and the aircraft "Falls Through"....which can result in an unscheduled landing.
The various techniques of flying a Tandem Rotor design, once learned, facilitate takeoffs and landings that in a single rotor helicopter would just not work.
In the Chinook an aggressive combat landing with good visual reference, includes a sideways flair which uses the huge flat belly of the aircraft and the rotor system as "speed brakes".
Rotating the Aft Head outside of the disturbed air of the forward head enhances performance....and if is done with a fair bit of boot at the right time will actually accelerate the aft head transition into translational lift.
The one thing that always caused me to smile was the way the Chinook felt like a Truck driving over a street curb when encountering Thermals....the forward head hits the uprising air and moves up...followed by the aft head which then does the same thing a moment later.
Water landings are the real hoot.....as was pulling water skiers....but the last is a story for another time.