Fly-Sky Configuration
and Helicopter Setup Manual

Battery Safety

Lithium-Polymer – (Li Po) is currently the most popular battery used in RC aircraft. The amount of energy they store is impressive. If handled correctly, they will serve you well over 300 recharge cycles.

Most batteries are hazardous. Lithium Polymer (Li Po) batteries are especially dangerous when abused. They are susceptible to heat, so never leave a Li Po battery in direct sunlight for extended periods of time. If you take an arsenal of batteries to the flying field, take them out of your car, or you may find yourself walking home after the car roast.

Once you have witnessed the flammable and explosive potential of these batteries, you will gain a new level of respect for this little power plant.

Purchase a set of LiPo bags, and keep them in the bags when they are not in the helicopter. Especially when charging the battery. They are most susceptible explosion during re-charging.

Designate a charging area (preferably outside). Make sure there is nothing flammable in the charging area. If you do not have a Li-Po bag, get a ceramic flower pot that has a ceramic lid. Dangle the battery inside the flower pot, and gently lower the ceramic lid over the opening so that you do not damage the battery wires (you can use a ceramic bit to gut notches in the lid for the wires).

Never use a puffed up battery pack. It is puffed up because it was over-discharged or over-recharged resulting in over heating and the laminates begin to separate. Overheating usually occurs because it was used near or below it's 3.1v per cell minimum voltage rating, or it was over charged beyond 4.2v per cell maximum voltage rating or used in an application that called for a higher C (current) rating than the battery could handle. Once a battery has “puffed”, the internal damage has been done. The battery may shrink back to its original size, but it is no longer safe to use because the internal laminates have become damaged and pose a serious out of the blue fire at anytime. Chemical reaction takes time, but once it is on its way, it can quickly escalate into fully functional chemical fire.

Time your flights. Most modern radios have built in timers just for this purpose. The objective is to never get the battery drained to the point where the ESC starts to shut down. Less is better. It is better to fly for 5 minutes at a time, and make the battery last for years, rather than over fly it, and kill it in a couple months (or less).

*Note – your throttle curve directly contributes to the amount of time you can fly. Higher speed, means the battery is draining faster.

Balance your battery at least every 5 discharges. Modern chargers use the main battery cables to supply recharge power, and a connector with 4 or more wires (called the balance plug) to monitor the balancing progress. If one cell is less than the others, the charger stops charging through the main cables, and applies charge (through the balance plug) to the single cell needing to catch up until it is even with the others, then full charging resumes until one of the cells again drop below the others. Lower cost battery chargers either only use the balance plug to charge the battery, or only the main cables. If you have a low end battery charger, do yourself a big favor and buy a real LiPo battery charger (I highly recommend the Thunder AC6 charger).

If you crash the helicopter. Remove the battery and set it aside for 15 minutes. If it does not explode or puff up in that amount of time, you can return it to service. Continue to monitor the battery closely the next time you charge it – oddly, you can often more safely discharge a battery than recharge it.

Never dispose of a LiPo battery with the common waste. Soak it in a salt water solution for 7 days, then it can be safely disposed of.

Never leave a charging battery unattended. I know of one story where the battery was left unattended for 15 minutes in the garage while the owner went into the house to get something. The battery burst into flames, and ignited other flammable containers in the garage, and lost the entire house. Chemical fires are difficult to put out.

Never charge a hot battery. It’s tempting to plug it in again right after you flew it, but give it a rest until it’s cooled to room temperature. Do not become impatient, wait for it to cool before starting a recharge. Alternate flying batteries per flying session. Number or tag your batteries, and use them and charge them in the same order.

Batteries should not get hot while charging. If they do, immediately unplug the charger. Do not move them until they return to room temperature. If you see the battery starting to puff up or smoke, it is an imminent fire.

A fully charged LiPo battery holds 4.2 volts per cell. If you are using a 3S LiPo, it will have a full charge of 12.6 volts.

*Note – Buy a good battery charger. The inexpensive chargers that come with RTF models are inadequate for this hobby. A good balance charger has built in safety features, and superior battery monitoring and charging capabilities. Your batteries will last for hundreds of cycles when using a good charger. It will easily pay for itself. These better chargers can also safely charge your larger/”higher C” batteries faster than more conservative chargers.

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