Micro Helicopter Introduction
Micro helicopters come in various types and qualities. The cheaper ones are fixed pitch (FP) and available from many sources. They are very limited in aerobatic abilities. One better value today is the “Cupid” which is supplied complete ready to fly with a four channel radio, batteries and charger for about 350 dollars. Best of all it is already pre-built so you simply pull it out of the box, charge it up and fly. Most micros in this category are generally clones of one another with very minor design variances. Some have poor quality motors which burn out very quickly during normal use. The Cupid comes with heat sinks on the motors to extend service life. Heat sinks are optional on some brands like the Century Hummingbird.
All micros use electric motors and eCCPM swashplate control may be implemented for those with collective control. The main reason for electronic swashplate mixing is to keep matters simple and light. The Piccolo Pro uses (mechanical) non-CCPM fixed swashplate and is somewhat more complicated.
The cheaper micros use rpm to control the tail rotor thrust while the better ones use a conventional tail rotor pitch change mechanism. By using a tiny dedicated motor on the tail rotor shaft a separate speed controller is needed in the onboard electronics to control yaw. Usually it is part of the helicopter package. By installing a motor at the end of the tail boom tiny mechanical tail rotor pitch change parts and drive train components are not required. Unfortunately yaw performance suffers in both power and reaction.
A fixed pitch machine is harder to control since a delay exists in waiting for the rotor speed to change. When the rotor speed changes so does the handling qualities of the helicopter. Wobbling and sluggish control often result when the rotor rpm decays and precision hovering close to the ground becomes near impossible. A fixed pitch machine is simple to maintain and repair, the acquisition cost is low and they often come fully assembled ready to fly. A turn key FP system ready to fly out of the box can cost less than a mid grade helicopter radio. A cheaper toy means a lower personal stress level while learning to fly plus knowing that mishaps will not break the bank account may speed up the learning process, so far as flying goes. Keep in mind that the included basic FP radio set is very limited for future helicopter application should you expect to later grow into a collective machine electric or glow.
The collective micro is capable of full aerobatics including 3-D provided the correct motor and setup is employed. Keep in mind that all micros are small and easily affected by windy conditions. Flying in confined areas is easier with collective control. While the collective machine has a few more parts it is just as durable as the fixed pitch machine for the most part. Due to the small size and scale structural factors, crashes similar in nature to a glow machine usually result in substantially less damage. The fixed pitch micro sometimes has a pop off rotor head which really reduces damage to the helicopter. The collective micro can be upgraded to a desired performance level by simply changing the motor and battery types. The collective pitch micro requires a dedicated helicopter radio with eCCPM mixing incorporated.
Micros are not the best for learning to fly but some do go this route. This is owing to the lower stability when compared to say a 30 glow machine. A more critical setup is needed with some micro machines. The micros are becoming very popular and hopefully will help draw people into the hobby provided they receive the proper assistance. This assistance issue applies to most all helicopters and can make or break a modeler. Some micros run carbon blades at high rpm (2500) so the danger of personal injury is present. Flying time is limited but lithium-polymer batteries are now changing that. Micros usually come with a NiMH-600mAh/8.4V battery allowing about 5 minute of sprightly flight time. Due to their popularity indoors and out and todays better performance, expect timely micro helicopter advancements.