Need help with a problem

[Hippie 64]

I have had a Freewing F9F for a couple of years now and it's fun to fly . But the last few times I have flown it I keep running into the same issue . The motor drops power ! The first time I chalked it up to a bad battery, then after that I thought maybe my RX was having a problem . Those things were changed and plane rebuilt but it happened on the next flight but I did get to record it . All of a sudden the motor power just drops . but will come back !!!! If you watch its better to do so on a computer so you can hear the motor cut out .

https://vimeo.com/179653369

Any input or ideas ????

Bryan

[AkumaZeto]

sounds like LVC to me

[F106DeltaDart]

Double check all of your solder joints. I had a similar issue with my Freewing F-104. It would work fine at lower throttle settings, but cut out after 50% throttle. I found out later that I could pull one of the bullet connectors off of the motor with hardly any effort, so there was a cold solder joint. Resoldered it, and it works fine now.

[Hippie 64]

I'm sorry I don't know what LVC means

[F106DeltaDart]

I'm sorry I don't know what LVC means

It means low voltage cutoff. I would be surprised if you are hitting LVC that soon unless there was an issue with your battery. What is the C rating on your battery? If it is too low, that could cause the voltage to drop off with higher current draw.

[Westsider]

I think Delta is right on the mark as usual with the diagnosis. Eflite's 280 motor, for the mustang, adagio, and the viking, is notorious for this. The connections over time, or sometimes right from the factory, come loose, especially on the mustang which is a belly lander. I have found the connections to the motor to be loose and actually contact other parts of the motor, which will make the motor rotate backwards sometimes, slowly and unwillingly. Wasn't a battery or LCV, in my case with this motor, i just re-soldered the connections and it went away.

[gooniac33]

Another thing to consider.... people always do voltage checks with the battery resting. You need to do a load test as well. connect the cell checker and then run the motor to full power. From what I am hearing you have a cell falling off. All 3 cells must be close in voltage or the whole system will not be able to support any load.