I think that Walkera’s designing engineers had one main objective in mind when designing the Walkera 4#3 (keep it light, small and simple). I must compliment Walkera. I think they have succeeded by designing a very small, light and simple four-channel radio controlled helicopter.

Technical and designing review: Let’s start with the main rotor. The main rotor blades are made from a strong durable plastic. They are a bit flexible, but in a good way. Due to the Walkera 4#3 light weight, the load factor on the main rotor blades are minimal, so the flexibility of the main rotor blades doesn’t affect the flight performance of the helicopter at all. You will get away with minimal or no damage to the main rotor blades when you crash due to its flexibility.

The rotor head assembly is basically the same as the Walkera #4. In the event of a crash, the main rotor blade holder will simply pop off from the main shaft minimizing any damage. The blade holder rock side ways on two miniature high quality ball bearings. The balancing bar for the flybar-paddles is made from graphite. The paddles can be adjusted by two little screws on the flybar connectors.

The swash plate is very simple with two servos connected to it via ball linkages. The swash plate bearing ensure for smooth cyclic movements.

The main shaft runs through the main frame on two ball bearings. The main gear is connected on the bottom end of the main shaft.

The Walkera 4#3 have two 3.5g servos. One servo for elevator, and one servo for aileron. As small as the are, they give precise elevator and aileron movement for excellent cyclic control. The servos simply clips into position on the main frame which make replacement very easy if necessary.

The main motor of the Walkera 4#3 is a brushed motor with strong magnets which give the helicopter plenty of power for its size.

The walkera 4#3 have a four channel receiver (elevator, aileron main motor and tail motor). The gyro and speed controller is build into the receiver. Unfortunately you cannot adjust the gyro sensitivity, but I found the gyro very effective as is.

The Li-Po (3.7V 400mAh) battery of the Walkera 4#3 gives about 8-10 minutes of flight time. It simply slides into the battery frame which make battery changes very easy.

The landing skids are made of extremely thin spring steel, and although they are very light, I think that they will handle hard landings with ease without breaking.

The tail boom is made out of a hollow graphite rod with the tail motor wires running through it.

At the end of the tail boom you will find the tail motor holder. The Walkera 4#3 have a brushed tail motor with strong magnets to ensure ample power to overcome the torque of the main rotor.

Although the tail rotor is very small, it is very effective through the reduction gears. The tail rotor shaft runs on two miniature ball bearings.

Overall the Walkera 4#3 have seven high quality ball bearings to ensure smooth running on all moving parts.

The Walkera 4#3 comes with a Li-Po battery charger. A red light will be on during charging, and a green light will flash after charging is complete. It will take approximately 40-60 minutes for the Li-Po to be fully charged after flight.

Setup: The Walkera 4#3 is a ready to fly out of the box helicopter. No assembling needed. Do an overall check for any lose components before your first flight . You need to charge the Li-Po battery of the helicopter, and for the transmitter, you need eight AA batteries. They are not supplied with the Walkera 4#3 kit.

Flight performance: Take care on you first flight. Don’t assume that the helicopter is trimmed correctly. Hover first and trim the helicopter so that it hovers still in one spot without any input from the elevator, rudder and aileron stickers on the transmitter.

Hovering the Walkera 4#3 is fairly easy once trimmed. Transition into forward flight is exceptional good for such a little helicopter. I found  a bit of nose down elevator trim makes forward flight much easier. Left rudder rotation is bit faster than right rudder, but who cares. This little helicopter is not a high performance 3D helicopter. It will still do about three 360 degree turns in one second with full rudder application.

The gyro works very well. The only negative thing I can say about the gyro is that the tail boom have a tendency to bounce slightly up and down with low main rotor head speed. Other than that, the gyro works fine. I get eight minutes of flight time on a full charge. Ten minute flights are achievable with hover flights.

The Walkera 4#3 is very silent during flight. You hardly hear any motor or rotor noise.

Reason to buy the Walkera 4#3
 

The Walkera 4#3 is a nice indoor helicopter.
It is quite easy to fly if you have previous flying experience.
It has a powerful main and tail rotor motor.
The build in gyro is very effective.
It can fly up, down, left right, yaw left and right and can hover still in midair.
It is cheap to maintain.
The parts are easily obtainable.
The Walkera 4#3 is quite crash resistant.
Transition into forward flight is really good.
It can be flown outside in zero wind conditions.
And its not that expensive to buy.

Conclusion: If you want a really small fixed pitch four channel helicopter, this little Walkera 4#3 won’t disappoint you. I highly recommend this new addition from Walkera. If you are a newcomer or experienced R/C helicopter pilot, you will have lots of fun flying this little engineering marvel.