Beginner RC Helicopter

Written: 13 Jan 2013

Last Updated: 30 April 2013

For the most up-to-date copy of this article, see its original posting location here:  http://electricrcaircraftguy.blogspot.com/2013/04/beginner-rc-helicopter.html

Related Articles:

• Beginner RC Airplane Setup

• Thunder AC680/AC6 Charger & Computer Data-Logging Software

• Parallel Charging Your LiPo Batteries

For those of you who have tried a 3-Channel micro helicopter or two (ex: virtually any helicopter that you might see at a mall), you are probably ready to try something a little bit better.  Well, don't go out quite yet and spend hundreds on a 6-Channel fully acrobatic collective pitch heli.  Rather, get a nice single-rotor 4-Channel beginner micro heli that can take some abuse while still teaching you more skills.  Once you master a micro 4-Channel heli, then take the step up to a several hundred dollar 6-Channel helicopter, and start flying slowly and carefully as it will be much more difficult still than the 4-channel heli.

So, which one to buy?  Well, I have the HobbyKing FP100 ($29 + shipping), and I love it! It flies very well, gives you those extra skills you need while providing more challenge and capability, and yet is still so light that it is durable and can take quite a few crashes without breaking.  And if you break it? --you can buy spare parts!

How is this different from a 3-Channel Helicopter? 

A 3-Channel helicopter has a left stick which controls throttle, and a right stick which controls pitch and yaw.  There is no roll control, and pitch is extremely limited, since it is done simply via a tiny horizontal propeller near the tail which spins to create lift and slightly raise or lower the tail, thereby providing forward or aft movement.  A 3-Channel heli, therefore, is very limited in control authority, and can rarely go faster than a walking speed.  Another serious limitation is that they usually use infrared transmitters, which have a very short range, and are affected by sunlight.  Therefore, they are usually only indoor helicopters due to their ultra limited control (inability to counter even the slightest wind gusts), and infrared antennas which are susceptible to interference from the sun.  (Note: infrared transmitters are usually identifiable by a small, usually red, plastic cover near their top, instead of an antenna).

So, what is the extra channel on a 4-Channel helicopter?  

A 4-Channel helicopter, on the other hand, is highly maneuverable in comparison to a 3-channel helicopter.  For a 4-Channel heli, the left stick controls throttle (up and down stick movement) and yaw (left and right stick movement), and the right stick controls pitch (up and down stick movement) and roll (left and right stick movement).  Whereas with the 3-Channel heli you were extremely limited and had only 4 degrees of freedom (pitch and yaw rotation; and up and down and forward and aft translation), with the 4-Channel heli you now have a fully-functional helicopter with 6 degrees of freedom (pitch, roll, and yaw rotation; and up and down, forward and aft, and left and right translation)!  How does this work?  Well, instead of the tiny horizontal propeller at the tail used to induce a very slight amount of pitch control, you have a conventional helicopter tail with a vertical tail rotor, and a main rotor with cyclic pitch controlled via a swash plate and two ultra micro servos.  In other words, through a specialized rotor head setup, a plastic mechanism in the rotor, called a swash plate, is actually tilted in various directions in order to cause the main rotor blades to pitch up and down as they rotate, thereby creating more or less lift in just the right locations throughout the rotation, so as to induce helicopter pitch and roll via gyroscopic precessional forces and the resultant thrust vectoring (want more info about helicopter control?  Visit here:  https://sites.google.com/site/electricrcaircraftguru/page-6-helicopter-control-explanation-gyroscopic-precession).

In other words, a beginner micro 4-Channel helicopter can now strafe rapidly left and right, and pitch forward or aft enough that you can get it to go as fast as a rapid sprinting speed.  Not only that, but the radio transmitter now uses a conventional antenna and has a range close to 100 ft.  Outdoor flying with the FP100 is easily possible in winds up to ~5 mph, and rapid flying and minor stunts (no loops, rolls, or inverted flight, however) can also be performed!

Note: the bar in the picture above, which lies above the main rotor blades, is called a flybar.  In "beginner" 4-channel designs, this flybar is at a 45 degree angle to the main blades.  This effectively creates a natural pitch and roll stability, or a slightly self-stabilizing tendency, in the helicopter in the roll and pitch axes--similar to what dihedral or polyhedral does for an airplane in the roll axis.  More aerobatic helicopters (such as 6-Channel helis) either have a 90 degree-oriented flybar, or no flybar at all (note: having no flybar requires a 3-axis rate gyro sensor computer-stabilization system, however)!  So....the FP100 truly is a fully functional, yet still an excellent beginner helicopter!

And how good of a deal is this?  Well, this $29 helicopter from HobbyKing comes to ~$50 with shipping, but would cost you over $100 to purchase a similar helicopter elsewhere!  Don't believe me? Check this out: 

Nearly identical heli here for $110.

Oh, and by the way, it comes with *everything* you need!--heli, radio, built-in servos and receiver, 2 batteries, and even a cheap little USB charger!  Want to upgrade and get more batteries?   See below for the link to the additional batteries I purchased for just over $1 each.  I had to modify the heli to make it work with these batteries, so if you want the details of that modification, comment below.  With my modification, the heli still works with the old batteries (the ones it came with) though too.  Want to charge up to 18 or more batteries all at once?  See the links below.  I use a couple special harnesses (items 3 and 4 in the list below) to charge all 14 of my FP100 batteries at once, on a single charger, in only one hour!  Pretty crazy right?  Here's the concept of how I do it; it's called "Parallel Charging."  Make sure to read my entire Parallel Charging article before you attempt this process, however, as it requires a solid understanding, unless you want to damage your batteries and possibly cause a fire.

Lastly, here are some other excellent, economical 4-channel micro beginner helis I'd recommend:

-HobbyKing HK-190:  http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=18746&aff=281904

-Xheli's H995, V911, or 9958:  http://www.xheli.com/4fixmicro.html 

Here are the links of extra things I recommend, as described above:

1. Nice charger - Thunder AC680, $55 with shipping: http://www.hobbypartz.com/73p-ac680-accharger.html
2. LiPo-safe (fireproof) charge sack, ~$3, or this smaller one, ~$2.  These are always a good idea to use when charging.  Place all your charge harnesses and batteries into this bag while charging.
3. Pico Parallel harness, $2 each (each harness does up to 6 batteries, so get 3 or 4 of these harnesses)
4. JST Parallel harness, $5 - this is necessary in order to plug in to your charger your 3 or 4 (or more....up to 6 max) Pico parallel harnesses above
5. Pico plug extensions, $2.50 - get a pack of these to use as plugs for modifying your two existing batteries, and the heli.  Cutting an extension in half allows you to use it as a plug.  Solder the female plug (I am describing the gender of the plastic parts, not the metal pins) onto your heli, and a male plug onto each of the 2 batteries that the FP100 came with).
6. Turnigy nano-tech 160mAh 1S 25~40C LiPo Pack, <$1.50 each - get as many of these as you want.  I recommend 6 or more for non-stop flying!
7. Super sticky velcro, $2.50/meter for a 3" wide roll - nope, not all velcro is created equally.  This stuff is better and has a stickier, more reliable adhesive backing than anything I have ever used before.  It is required to velcro your new batteries above onto your slightly modified heli.
8. Make yourself a good little battery voltage checker.  Most battery checkers are powered from the battery whose voltage they are measuring, but they don't function well (if at all) on a single-cell LiPo battery.  Therefore, you'll need external power for your battery checker.  For 1S LiPos I just use this cheap 7 Function Digital Multimeter from Harbor Freight Tools (shown below).  It is listed as $5.29 on their website, but I got it for free using a coupon, and I've seen it discounted many many times for ~$3.  It works surprisingly well for such a cheap device, and I've compared it against a nicer digital multimeter when measuring a variety of DC voltages (V), as well as resistances (Ohms) and diodes (forward Voltage drop), and I've found it to be much more accurate than I would have thought.  The test lead receptacles take 4mm banana plugs/bullet connectors, so you can plug your battery into a Pico Parallel harness, then plug that into the JST Parallel harness, and plug that into the multimeter, to easily test your 1S LiPo voltage.  Remember, for LiPo batteries, 3.0V/cell is empty, 3.7V/cell is ~20% full, and 4.2V/cell is 100% full.