As an Hawaii commercial drone pilot based in Hawaii, I’m often requested to fly drones in fairly high winds. On Maui there are typically winds that are in the 20-to-30 knot range with gusts reaching the 40’s or 30’s. When I’m assigned an aerial media capture job in wind , I must assess and decide whether it is safe to fly without risking the drone, or flying too fast or causing injury to someone. Naturally, an “no fly” call is not a good idea and typically results in an immediate loss of money in the fast-paced business drone QR code invoice market. A lot of the time, this high-wind flying takes place on the water (shark plagued sea water, to be precise!) which can increase the risk and difficulty of the task. Additionally, as you be aware, dropping a drone into the ocean’s big blue kind of ruins your chances to obtain a replacement through insurance like DJI Care Refresh, unless you are able to retrieve the drone and return it to DJI. The good thing is that you typically don’t have to contend with obstacles on water, and images are rarely disrupted because of object interference. However, when you encounter a problem you must first travel an extensive distance across No Man’s Land before you even have the chance of getting your drone back.
To get ready for a scheduled drone flight, like kitesurfing, for example I perform a few things. The first step is to determine whether the area I’m planning to fly at is in a “green zone”. This means that it’s not located in an FAA no-fly zone, and is not less than 5 miles from the airport and also has an authorized launch and landing space within the visual view distance of the drone’s zone of operation. The next step is to make sure that I have the permits, insurance and FAA approvals needed to complete the task. After the location has been approved, I verify the weather conditions in the area and conduct a pre-shoot survey, and then draw up an outline of the shooting plan as well as a plan to handle emergencies based on the current winds and the topography of the coastline. Then I schedule my assistant to shoot, as a visual spotter is legally required and highly recommended for anyone who wants to push the boundaries of a drone’s capability to fly.
What I’m trying to find when I look up the weather is whether there will be sunshine (drone shots require sunlight) and how strong the wind is. The gust factor that the wind produces is an important factor. The variability of the wind can seriously affect the experience of flying and may make the drone roll and pitch much more frequently than a steady winds. Based on the speed of the wind, I can determine if my drone is able to handle the higher limit of the forecasted wind. The direction is also important. Offshore winds pose a higher risk than onshore winds when flying over water , for obvious reasons. Also, I take into account the weather conditions when deciding not just if I am able to fly, but also the distance, what’s the subject doing, are there other obstacles, the range of my drone and what is a safe altitude. Kitesurfing is an extremely fast-moving kite at the end of the 30 meter lines therefore any shots that are less than 100 feet must be considered in light of this and the its risk.
On the day of shooting, you need to evaluate the conditions of the wind and weather (don’t be caught in the rain) and then decide whether flying or refusing to fly. I prefer to perform this prior to clients or other production elements arriving so that I can make my decision without bias. If it’s an “go” situation I fly my drone using normal GPS mode for about 10 feet , and then see whether it is able to stay in the same place. If it’s really windy in the area you are launching from, do not launch from the ground, or the drone could flip before taking off. If you can hover in the air without losing ground, try flying to the maximum altitude for shooting and then test the speed of wind there. If the wind begins to take over your drone and it starts to drift away, bring it back down to a lower elevation and attempt to retrieve it. If it’s too windy for you to retrieve your drone using GPS mode, you could switch into “sport mode” (DJI Mavic Pro series and Phantom 4 series) and return it to your. Be sure to be familiar with the process of switching to and flying in”sport mode” prior to taking flight. When your drone is drifting away , it is not the best moment to review the setup menu to the very first time. If sport mode isn’t an option, and there are obstacles in the area, you can use them as windbreakers. If you’re flying the drone towards you at full speed , and the wind is still consuming the drone, you can fly it behind trees, buildings or barriers and even mountains to enter an environment that is more stable. While obstacles can cause the wind’s variability, I’ve found that the combination of lowering the altitude of your drone and avoiding objects that slow the wind could get you out of the majority of situations and let you get the drone to the ground , not into the water. If the winds are blowing away from shore and into the sea there are a few alternatives for recovering and the wind could be as strong at 10 feet from the ocean as up 100 feet. The strongest and (typically) turbulent offshore winds pose the greatest chance that your drone could be lost in water , and should be approached with extra care.
In the end, remember to be secure, not regretting it. Do not put your drone in an unfixable situation. Have multiple backup plans in case of emergency. Be aware of your equipment prior to flying over or in the wind. Know your drone’s limits when you’re flying through water, including distance and time limitations as well as the effects of wind on relative speed and surface speed. If, for instance, your drone is flying at 25 MPH at its top speed and is soaring 15 to 20 Mph , it could fly downwind at an average speed of 45 Mph, but it may be able to fly upwards at 5Mph. If your drone travelled one mile downwind, make sure that you have enough battery power to allow it to return upwind at 5 Mph according to my calculations, this would take about 12 minutes. Additionally “sport mode” increases speed however it reduces battery life. Also, try to not fly your drone when it’s empty. The performance of your drone may be lower than you’d expect when your battery is low, and it certainly increases stress levels when you’re in the single digits but not returning to the shore.