Plane loses power mid flight
- Thread starter Boiii
- Start date
The buzzer did not start to beeep.It was set to 3,9v
bwarz
Master member
Cold temps can shorten your run time, and temperatures below freezing would definitely shorten your flight time when your battery drops to outdoor temps.
I don;t remember seeing - is this a brand new battery? If you are comfortable with it, you could have a friend hold the plane back by the tail and you test your voltage at a good throttle to see if you are having an appreciable voltage drop. If the battery is starting to show age, its internal resistance creeps up. More resistance at higher current draws (even 10A) will cause more of a voltage drop as seen by the motor.
Also, note what @Merv suggested - use your battery tester and see if all cells are very close in voltage immediatly after a flight.
The batteryy is new and all cells were about the same voltage after flight
FlamingRCAirplanes
Elite member
It’s the cold. Mine cut out unless pre warmed at just 20° f. And that’s on my truck!
Definitely, the temperature is an issue. I fly down to about 20F, not sure what that is in C. My batteries with start showing the effect of cold around 50F, and slowly loose their bunch as the temperature drops.
During cold weather, I keep my batteries warm, stored at room temperature. Then inside my coat, until they are put in the plane. Even with that, my flight times are cut in half. What would normally be a 10 minute flight is now 5.
If your batteries are not being kept warm, the cold could be the problem.
FIY, I’m a thumb flyer, I cut a slit in my gloves and poke the sticks through the slit.
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Piotrsko
Master member
As an aside: batteries are chemical processes. The reactions prefer a comfortable human temperature to be efficient. At lower than t shirt weather, the processes slow down. at freezing they almost stop. Would you go flying in a snowstorm just wearing a T shirt? Voltage/current applied to motors need lots of reactions going really fast.
CappyAmeric
Elite member
Yikes! Way too cold for a lipo. If you want to fly in cold temps, get some chemical pocket warmer packets and place them in a lipo bag before you set out to fly. That will warm up the lipo for at least a few minutes - but the colder it is outside, the faster the lipo will cool down to an inexceptable temp.
quorneng
Master member
It is possible to fly a LiPo in zero air temperatures but you have to start with it warm and insulate it the battery compartment!
Under normal flight conditions a LiPo generates some heat during the flight so you have to make sure the heat generated matches the rate at which it is cooling down.
Of course in hot conditions the LiPo is likely to be unable to remove the heat during discharge and can be permanently damaged. In the summer it may be necessary to cool the LiPo or simply not use lots of full power, however removing excess heat from a multi cell LiPo is not that easy as the middle cell(s) in a pack are completely covered.
Not for nothing do electric cars with lithium chemistry batteries have complex battery cooling systems yet suffer a loss of range in sub zero temperatures.
Under normal flight conditions a LiPo generates some heat during the flight so you have to make sure the heat generated matches the rate at which it is cooling down.
Of course in hot conditions the LiPo is likely to be unable to remove the heat during discharge and can be permanently damaged. In the summer it may be necessary to cool the LiPo or simply not use lots of full power, however removing excess heat from a multi cell LiPo is not that easy as the middle cell(s) in a pack are completely covered.
Not for nothing do electric cars with lithium chemistry batteries have complex battery cooling systems yet suffer a loss of range in sub zero temperatures.
