After spending some hours, day and weeks flying a mini coaxial heli you found that it is fun and you want to experience more. The following models from this shortlist are able to fly outdoors on calm days. They all are real 4 channel helicopters with gyroscope, fixed pitch, mini size approx. 22 cm, 2.4 Ghz remote control.
Nine Eagles 25046 – Solo Pro 4 2.4 GHz
click for more reviews: Nine Eagles Solo Pro
Controller switchable Mode 1 & 2
powerful & lightweight (27 g)
very stable hover
adaptable servo reaction for indoor use or beginners
The next step would be a 4 channel mini helicopter. Still I will focus on models for indoor play and use. Keeping in mind that the requirements have developed since 3 channel coaxial helicopters it is difficult to find adequate and challenging products. Still valid are the general hints concerning the LiPo accumulators. They will increase the lifetime of all models.
There are several options for 4 channel helicopters. The first and most easy option to build is an avatar style heli with additional motors and blades on each side.
More advanced models use a swashplate to control forward and backward flight. Like the following models:
Simulus GH-424 2.4 GHz
click to see more pictures and reviews: Simulus GH-424 2.4 GHz
A coaxial helicopter has two main rotors. The helicopter will rotate if one of the two motors/rotors spins more slowly or faster than the other. By changing the speed of one rotor you will generate a torque, which will make the helicopter rotate. The torque of a hovering helicopter is zero. Thus, if one of the two rotors spins faster than the other, the helicopter will rotate in the same direction like the faster spinning rotor. In simple fixed pitch coaxial helicopters the horizontal tail rotor is responsible for forward and backward movements. Continue reading →
What to tell about mini- and microhelicopters? You have to use them indoors. Outdoors only during calms with absolutely no wind. All of these make use of LiPo accumulators and it is best, if you let them rest for at least 10-15 mins. after flight in order to cool down the LiPo accu before charging again. Also it is a good advise not to fly these accus empty. When the helicopter starts to sink (sounds hard) it is time for a cool down and recharge break.
It seems that there are only a few model types out there and all others are based on them. Often just the design or some details are different. Be careful to buy a model with gyro stabilization, makes it really easy to fly. The following models are all 3 channel koax helicopters using a gyro stabilization.
Never run the LiPo empty
Cool down before recharge
Power/speed off immediately when crashed
Be careful with the ceiling the most sensitive part is often the balance bar
Infrared works not outside or in bright sunshine conditions
My recommandation in this category for indoor & outdoor (calm days) flights:
Zoopa 150 Turbo 2.4 Ghz (seems to be based on Syma 107g)
click to see more pictures and reviews: Zoopa 150 2.4 Ghz
2.4 Ghz remote control (works almost everywhere, long range)
2 speeds / turbo
crash set and spare parts available
not so sensitive to wind, more “heavy” model (40g)