0406-904 Tandem 50scale CH-47 CHINOOK
	Length : 955mm Height: 405mm Width: 235mm Rotor diameter: 1,089mm Gear ratio: 1:9.625 Wood main rotor included Muffler included Servo mixer and gyro included 50 size engine and transmitter (more than 9ch recommended) are sold separately Picture is a sample helicopter. Fuselage included in this kit is not painted.  Specification may change without prior notice for improvement. This helicopter kit is for expert pilots only. Beginner will not be able to assemble nor fly this helicopter.   is a patent for SANWA Electronic Instrument Co. Ltd and Japan Radio Control Co. Ltd. HIROBO is licenser of SWM-system.

The world's first tandem RC helicopter KV-107 Vertol was released from HIROBO in 1988. After 16 years, this model is redesigned with new technology. There is no complex linkage anymore. TR-SVMIX and 3 axis gyro (included) made this helicopter a lot simpler. 50 engine will ensure enough power for flight. You will thoroughly enjoy flying new Chinook.

TR-SVMIX ;Tandem Roter Servo MIXer This mixer controls 2 swash plates at the same time. Since tandem has to control 2 swash plates at the same time, linkage will be very complicated if mechanical mixing is used. TR-SVMIX included in this helicopter changes signal from normal mode transmitter to swash mode. SWM signal is transmitted to 6 servo in front and rear. Complex linkage is not necessary anymore and setting can be done by input to this TR-SVMIX.

GYRO 3 axis gyro is included with TR-SVMIX. This 3 axis gyro stabilizes aileron, elevator, and rudder. Sensitivity can be adjusted from TR-SVMIX. If GYR Rem (Gyro remote) switch on TR-SVMIX is turned on, adjustment can be done from transmitter for 1ch only.   Please note: Only this 3 axis gyro can be used for this helicopter. Gyro must be connected to TR-SVMIX to use the mixer. TR-SVMIX and 3 axis gyro cannot be used for other purpose.

Muffler for 50class engine & Wood roter Muffler for 50 engine and wood rotors are included in this kit. This rotor can be used for 0406-902 32-46 Vertol and MRB-III 3 blade rotor head.

Black anomized aluminum flame

Main frame was newly designed for powerful 50 engine. Linkage for 2 swash plates is

Engine 50 engine can be used (Not included). This helicopter is shaft start.

What is a tandem rotor helicopter?   In tandem system, 2 rotors in front and rear counter rotates to each other to negate counter torque. Tandem is more efficient than tail rotor because 2 rotors are used to create lift.

How is Flight?   Elevator is unstable because elevator is most sensitive in tandem. Rudder reacts slower than normal tail rotor. For better scale looking, 3 blade rotor head is used. Compared with normal head with stabilizer bar, tandem rotor head is less stable. Knowing tandem characteristics are important for flight. Also, this rotor head will be affected by wind. Flight in strong wind is very difficult. We recommend first flight and adjustment in calm day. Due to helicopter design, this helicopter cannot do any acrobatics like loop and roles.   During hovering, helicopter will look like below picture. Rotor RPM Rotor RPM should be about 1,500-1,600 rpm. With lower RPM, helicopter will be unstable and hard to control.   Gyro sensitivity Gyro input should be same as data sheet in manual. Minor adjustment will be required during flight. Low gain will make helicopter unstable. High gain will cause hunching.   Flight in air After hovering adjustment is completed and you feel comfortable flying this helicopter, try some turns in the air. If there is sudden stick move during forward flight, it can cause a stall. Rotor RPM in the air should be 1,600 - 1,700 rpm. High speed can cause sudden unexpected move. Be careful with orientation of this helicopter. It is very easy to lose orientation.