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Mikado LOGO 20 Electric Helicopter Review update

Although I was pleased with the nice comments passed to me about the review I wrote about his awesome electric heli, I think that folks were being kind. I was almost a complete newbie, going it alone, when I wrote it. There were a few errors which caused needless concerns as indicated by some email I received over the past two years. Regarding motor rpm control, I wrote: "I realized that I was purchasing myself into a corner because all of a sudden my perfectly fine RD6000 radio wasn't quite good enough. A separate auxiliary channel with a rotary or sliding knob was required for the speed control." A separate rotary switch isn't really needed for motor speed - one can control motor speed with 3 settings on a flight mode switch. See the throttle setup page. I was a "late adopter" of this method, trying it when I wanted to start practicing autorotations because I could not get the TH switch programmed to give 0 throttle while using my earlier setup. Although the rotary knob gave predictable, consistent rpm settings with its ratcheting action and markings and was very easy to use and setup, I have to admit that I like using the throttle hold switch better now. One caution with this method is that it is a LOT easier to accidentally start the motor by knocking a switch or the throttle stick, especially when using a Radio Glove. To help with this issue my variation of this method has a substantial "dead spot" at low throttle and I leave the TH setting at zero throttle. Insufficient pitch range turned out to be, as I had suggested, a non-issue caused by my ignorance. The solution to getting more pitch without increasing elevator/aileron input to the mechanics was easy, once I understood what the CCPM mixing percentage settings in the JR8103 transmitter were for. I had thought that they should remain more or less equal for some stupid reason. Increasing the pitch % from 60% (as the aile and elev are set) to 80% gave me lots more pitch range without increasing the aileron and elevator response and causing binding. See my comments in the tips section. With the Pletti motors the correct flight mode is the so-called high speed mode because the number of poles in thiis motor is eight

Regarding my comments about glitches on my first LOGO: A specific ferrite ring is now recommended. The Kontronik {Ringkem-Entstorfilter (2 dots over the "o") Best.Nr.:9700}ferrite ring has been found to reduce interference caused by the motor and speed control. It is installed on the ESC's receiver lead near the receiver. A 6" receiver extension just fits for the recommended winding on the ring. With this ferrite ring and also switching to the Futaba GY401 gyro, my LOGO 20 has been absolutely glitch-free for the past two seasons! The issue of bent rotor attachment bolts is gone now, even at higher rpm's. I have flown the heli lots at 1800+ rpm. Using bolts with longer shanks helped with this issue and there were perhaps two factors that made had matters worse: I made a mistake during assembly of the first LOGO which I only caught towards the end of its life, at around 200 flights. If you look in my article's photo of the rotor head you might notice that the ball bolts are positioned too close to the main shaft, making the double links not parallel to the main shaft. It seemed to work fine this way, but it was not correct. Also, I wonder if there was some characteristic of the high lift mini-S blades that made the problem surface. I never mentioned this in the review, but the width of the Pletti motor's end bell causes the frame to spread apart a bit. I was told not to worry about it and this has not been a problem. Also the width of the motor's cooling fins caused contact with the batteries when they are strapped in place. I have always used rubber or stiff foam spacers held in place against the frame with double sided tape Although I have not had any experience flying the heli without these spacers, I can only imagine that allowing the the fins to be pressed into the battery's heat shrink is a recipe for disaster.

DISASTER! My first LOGO 20 was destroyed on its 221st flight. I had only recently upgraded to carbon fiber MS 600 blades and was enthusiastically exploring the joys of easy inverted flight with symmetrical blades. I found out after the fact that the lower limit of the Telebee gyro's operating range was -5C and I was flying the heli on a nice, sunny, oh, -5C day. It was hovering inverted and many mistakes high, when all of a sudden it kicked into a fairly rapid pirouette and I had not yet thought about and rehearsed a recovery for that one. It hit inverted, nose slightly down, and full throttle. The ESC and motor survived and I think this was due to the safeties built into the Schulze controller. All the radio gear was good, but I only reused the PCM receiver. The switch was replaced because after over 200 flights, it was time for that.

Reality check - this can happen to YOU!