As usual, Clint’s funfly is a must attend event full of pure fun and nothing but people with love for the hobby. This year was no different from the past years. I arrived on Thursday night and immediately got to work on the prototype E9. I have been battling a problem with the E9 for a while and the next step was looking at flight logs to determine what the problem might be. Clint acquired a Castle Creations ICE160HV for the E9 testing/troubleshooting so we started soldering as soon as I stepped out of the truck. The problem I was having with the model seemed motor/esc related, under very small load, the ESC would shut down like it was experiencing and over amp issue and then recover seconds later. Upon looking at the flight logs, we noticed the motor rpm would increase and amp draw would decrease then the ESC would shut down. Initially we thought the motor was getting saturated due to the weight of the helicopter along with high output ThuderPower 45C packs. After testing all day on Friday with three different motors and two different ESC’s, we knew there was something else going on but couldn’t put a finger on it.

Seeing that the weather was going down hill I decided to take my crippled E9 home and give it a thorough checking. Saturday night Clint called me and told me that Bobby Watts had mentioned to check the auto hub for slipping just in case. I thought to myself… similar to a nitro heli we would probably hear the gear train changing speed if it was slipping but I was willing to try anything at that point. I took the auto hub apart, cleaned the outer steel race thoroughly, reinserted the outer race with loctite just in case it was slipping, and finished reassembling the model. The next day I was quite happy to see that the prototype E9 was again issue free and pulling like a freight train! I learned something new in troubleshooting large electric helicopters, If the motor is allowed to slip even just a little bit during a heavy load, the ESC can lose sync with the motor and completely shut down. Without the Castle Creations ICE160HV logging, it may have taken much longer to figure out what the issues was. Thanks to Castle Creations and everyone else who lent me a hand with the E9 troubleshooting. Applying loctite to the autohub outer sleeve will definitely be part of the conversion kit manual.