Before you fly a Co-axial Helicopter
It only takes a moment to check your helicopter to be sure it is ready to fly. You should perform this inspection every time you fly it so you don't lose control and crash, and also to be safe.
Pre-flight Checklist
1. Broken parts - check the skids, tail boom, mechanical moving parts. Don't fly with broken parts. Repair them or replace them.
2. Main rotor blades - check for cracks or breaks. Don't fly with broken blades.
3. Control links - ball links and connectors from servos to the swash plate must be in place.
4. Center of Gravity - with main blades straight and the flybar perpendicular to the fuselage, hold the heli by the flybar. It should be level or very slightly nose-down. Move the battery to adjust the balance.
5. Turn on the transmitter (Tx) with the antenna fully extended. Always turn on the transmitter first. This is important! If you plug in the flight battery without turning on the transmitter the main blades may start turning and the model can even take off by itself! You will not recover control before it crashes. After you turn on the Tx place it out of the way so you will not accidently hit the left stick while you are getting the helicopter ready to fly.
6. Plug in the flight battery on the helicopter. (The plastic 'JST' connector only allows you to plug the wires in the right way.) Wait for the LED (light-emitting diode) on the 4-in-1 in the helicopter's nose to stop flashing and show steady green.
If the 4-in-1 keeps flashing the throttle stick may be raised. If it alternates between red and green the radio link is not established. Push the throttle down all the way. If the LED shows steady green you are good to go. If it keeps flashing or shows red you need to track down the cause. The radio crystal on the Tx or the receiver (Rx) in the model may not be seated. You can remove the crystals, see how they fit, and carefully re-insert them.
7. Slowly move the left stick upward to gradually spin up the main blades to 30% or 40% power. Do the blades turn smoothly or is there vibration? A bent rotor shaft can cause the heli to vibrate. So will cracked or broken or unbalanced rotor blades. If the tail swings insistently to the left or right the gyro settings may need to be adjusted.
If anything seems out of kilter or suspicious you must find and cure the problem before flying.
8. If the rotors turn smoothly, the heli doesn't spin, and there is good power you are ready to take off.