Firstly,you should understand what is 3D remote control helicopter, this simple answer is, at least for inverted
hovering helicopter, not backward flight, the aircraft is upside down, belly to the sky!
What is the electric 3D RC helicopter? What is the oil dynamic 3D remote control helicopter? Electric battery power source is to the helicopter, not an ordinary dry cell or alkaline batteries, but the use of nickel-cadmium (basic eliminated), nickel hydrogen, lithium polymer rechargeable battery. Action is to use fuel oil as a power source remote control helicopter, general use of methanol and lubricant and nitro methane was mixed oil, or use gasoline mixed with lubricant oil.