Winter Drone Flying Tips
The winter offers unique opportunities for both professional and hobbyist drone pilots to take great aerial photos and videos. If you have your Part 107 certificate, you can sell those shots and that footage through stock photo agencies.
There's a big market for winter stock photos and video footage; but many stock photographers and videographers basically take the winter off, at least as regards working outdoors. Photographers and videographers who also are sUAS pilots and who are willing to brave the cold therefore face a lot less competition.
Extreme cold weather, however, also poses a unique combination of challenges. Cold temperatures affect the drone's handling characteristics, the battery charge life of the drone and the controller, and the health and safety of the pilot himself or herself.
This page discusses some of the challenges drone pilots face when flying in the winter, and provides some common-sense information for safely flying your sUAS in cold weather.
How Cold Weather Affects Your Drone's Performance
Every drone's specifications define minimum and maximum operating temperatures. For example, my Autel EVO II Pro 6K is rated for an operating temperature range of 14° to 104°F (-10° to 40°C). A drone's rated temperature range takes into account the effects of temperature upon all of the drone's systems and handling characteristics, and should always be adhered to. Let's look at a few of the most important factors individually.
The Effect of Cold Weather on Your Drone's Battery Life and Health
Cold temperatures shorten battery life; and extremely hot or cold temperatures can damage your drone's batteries. The theoretical lowest temperature at which LiPo batteries can be operated at all is quite low: about -58°F (-50°C). But you'll start noticing shorter battery life at about 50°F (10°C); and at 20°F (-7°C), your battery life may be reduced by as much as half.
The good news is that drone batteries rarely get that cold in real life if you follow the common-sense practice of keeping them warm until they're needed. This can be as simple as keeping them at room temperature until you leave the house, turning the heat on in your car on the way to the shoot, and keeping extra batteries in a well-insulated case inside your car until you need them during a shoot.
Specialized drone battery cases also provide some insulation and improved safety for your spare batteries while they're being transported, or while they're sitting in the trunk of your car between battery changes while on a mission.
Another important rule is to let your batteries warm to room temperature before charging them. LiPo batteries should always be charged at room temperature. They can be permanently damaged if you charge them when they're too warm or too cold. When you get home from your mission, let your batteries sit at room temperature for at least a couple of hours before charging them.
Drones and Snow
Obviously, you shouldn't fly while it's snowing. It reduces visibility, increases the chance of electrical short circuits, and dramatically increases the risk of icing. But snow on the ground can also be a hazard. The propellers can stir up loose snow and it can be drawn into the cooling intakes. Always use a weighted drone landing pad when taking off or landing a copter-type drone in the snow.
How Icing and Frost Occur and How they Affects Your Drone
(The section on icing and frost has been moved to its own page.)
Cold Weather Makes Your Drone More Fragile
Most drones have a lot of plastic parts, and plastics tend to get brittle in extreme cold. Propellers are especially prone to breaking in the winter, so be sure to carry spares.
Moving Parts Tolerances Change in Cold Weather
The moving parts of your drone are designed to maintain appropriate tolerances within the drone's operating temperature range. Operating outside the manufacturer-approved temperature range can affect those tolerances due to expansion and contraction of the moving parts, which in turn can damage your drone.
Cold-Weather Condensation can Damage Your Drone
Changes in temperature can cause moisture to condense on the moving parts and electronic circuits of your drone. This is more likely to be a problem when you bring your drone inside after flying in the cold than while flying in the cold.
What happens is this: If you wear glasses, you've surely noticed that they fog up when you walk from the cold outside into a warm house. That's the moisture in the warm air condensing on your glasses. Well, the same thing happens when you place a cold drone in the warm air of your car or your home. The moisture condenses on and inside the drone.
One simple way to avoid this is to carry a plastic garbage bag or a huge ZipLock bag with you when you go out to fly on a cold, dry day. When you're done flying, put the drone inside the bag (with its warm battery still attached or inserted), tightly seal the bag, and set it someplace safe in your heated car while you drive home. Then leave it sealed in the bag for a few hours at room temperature once you get home. That will allow most of the moisture in the warmer air to condense on the bag rather than inside the drone.
After a few hours, carefully remove the drone from the bag and let it sit outside the case for an hour or so. When it's time to stow it, throw a few silica gel packets in the case to absorb any remnants of moisture. Replace the silica gel every time you stow the drone during the winter.
If the relative humidity is high while you're flying, you're better off turning the car's defrosters to maximum temperature and fan speed on the way home and leaving the drone out of the case. The defrosters dry the air as well as heat it, which should help pull the moisture out of the drone.
Cold Weather Affects Your Drone's Flight Characteristics
At a given pressure altitude, colder temperatures increase the density of the air, which reduces density altitude. Or in simpler terms, cooler temperatures reduce what the altitude "feels like" to the drone.
What this means in practical terms is that your drone will likely to feel more responsive and zippy on a cold day. It's also likely to ascend more quickly. The differences in handling make it a good idea to fly around for a bit to get a "feel" for how your drone is flying on a cold day, before commencing your actual mission.
How to Stay Warm when Flying a Drone in the Winter
The biggest problems facing drone pilots who operate in cold weather are keeping our fingers warm and keeping our feet warm. Let's look at the fingers first.
Most drone controllers use touch screens, either built into the controller itself or on a phone attached to the controller. That means that you can't use just any gloves while you're flying a drone. You need winter gloves designed for use with a touch screen. These gloves have conductive surfaces either in the fingertips, or conductive fibers woven through the entire glove, that activate the screen's capacitive touch system.
My favorite touch-screen winter gloves are Moshi Digits Touchscreen Winter Gloves. They're not perfect; but they're reasonably warm, don't affect my dexterity vent much, and have excellent touch-responsiveness. It only took a few missions before I barely noticed that I was wearing them. I have a video and more-extensive review of the Moshi Digits gloves on this page.
Hand warmers are also good to have when flying a drone in the winter. If you don't fly often in cold weather, then disposable hand warmers are an economical choice that will work just fine. You squeeze them, they get warm, and you throw them away when you're done. If you frequently fly in the cold, you may want to consider rechargeable hand warmers that can be used over and over again.
To keep my feet warm, I personally just use good insulated winter boots and insulated woolen socks. That combination has always been enough for me. My personal favorite winter boot is the Oboz Bridger for the combination of warmth, comfort, and traction; but there are many excellent winter boots out there. As for the socks, I really haven't noticed much difference between different brands of woolen socks.
People who need some extra warmth in the feet often use rechargeable heated socks, which I'm told make a big difference. But I personally haven't tried them.
General Cold Weather Safety Tips
- Wear layers of clothing that can be shed in layers if needed. Perspiration from overheating will eventually make you colder.
- Wear a winter hat and a scarf to protect heat loss from the head and neck.
- In extreme cold, cover your mouth to protect your lungs from cold, and your nose to protect it from frostbite. Full-face ski masks are a good investment for really cold weather.
- The fall and winter are hunting seasons in many places, so make sure it's obvious that you're a human. Avoid wearing animal-colored clothing, and always wear your reflective drone pilot vest or another highly-visible outer garment whenever operating during hunting season, regardless of the temperature.
- A red LED armband like those made by BSEEN will make you easier to see when everything around you is covered in snow.
Revised November 26, 2022