What I Learned From 1,000 Professional Drone Flights — With Pablo Sandoval Mastandrea of 21SUR Aerospace, Uruguay

With over eight years of fixed-wing UAV experience, spanning over 1,000 commercial flight operations, the founder of 21SUR Aerospace, Pablo Sandoval Mastandrea, knows a thing or two about what makes commercial drone operations work. Here he talks to Waypoint about his team’s many learnings and how crucial BVLOS work will be to the industry’s continued growth.

Hi Pablo, could you tell us a little first about 21SurAerospace? What is the company’s area of operation there in Uruguay?

Sure. 21SUR Aerospace is a remote sensing company. We combine the analysis of satellite images with fixed-wing UAV mapping in Beyond Visual Line of Sight, or BVLOS, mode. Our differentiator is, therefore, the ability to survey large areas beyond visual line of sight, spanning out to country-wide operations, with a focus on the agricultural and forestry industries.

Our experience goes back to  2009, where we had the honor of operating a fixed-wing UAV—for a large agro company—for the first time commercially in Uruguay. We were then also the first operator to fly in BVLOS mode, using a UAV aircraft weighing 55 kg, which had a combustion engine and a four-meter wingspan!

We know that BVLOS is the future of commercial UAV operations.

For this, it was obviously important that we work closely together with the Uruguayan aeronautical authority (DINACIA), which we’ve done since the year 2010. This allowed us to fly the first commercial flights in Uruguay beyond visual range.

Now, we want to make this experience available to other companies across the world that want to start operating in this modality, so we are exploring alliances with professionals from other countries. Our eight years of experience will, we think, be helpful in enabling BVLOS operations to be extended in a safe and professional way. We know that BVLOS is the future of commercial UAV operations.

21Sur Aerospace uses two senseFly fixed-wing UAVs, which for larger projects its team flies in multi-drone or ‘swarm’ mode.

You recently reached a fixed-wing milestone—1,000 commercial flights! What would you say are the top three lessons you have learned from this experience?

Firstly, a larger UAV does not always mean that you can map a greater area.

Our platform experience led us to transition from the military-grade, great-performance unmanned aircraft that I mentioned before, to operate today small electric-powered eBees. However, the challenge then was: how could we get our operations to maintain the same daily mapping capability?

We have carried out successful operations with our eBees where they flew up to four kilometers away from our ground control station, without problems.

For example, in the past, we wasted entire mornings with our large UAV because it required a runway of at least 150 meters. With the eBee, we can take off in a matter of minutes.

The purchase of our second eBee helped even more by allowing us to make simultaneous flights—in ‘multi-drone’ or swarm mode—which, besides being fun, allowed us to achieve practically the same daily amount of mapping as our previous long-distance UAV. Thanks to this, we have carried out successful operations with our eBees where they flew up to four kilometers away from our ground control station (GCS), without any problems.

“Our truck becomes a ground control station in just a few minutes,” Pablo explains. “We run the two eBee’s PCs alongside each other for clear communication between the two pilots.”

Our second learning was that using drones convinced us these are the ideal tools for providing quality map outputs, and a guarantee for our customers.

During summer 2017 we made flights over 13,000 hectares of soybean and corn fields… without even a single shadow of cloud!

Speaking as a GIS specialist, I have worked many years with satellite imagery. This has taught me that, with satellite data, certain diagnoses are impossible to achieve at the exact time when they would be the most useful for the customer.

Generally, the most accessible satellite images—Landsat 5, 7 and 8 at first—were only available after a 15-day wait, plus sometimes the expected satellite image would show our target field completely covered with clouds. This meant, for example, that one year we were unable to provide a grower with information about his crops during a critical period—when he was close to making a fertilizer application or to apply his phytosanitary products. With the UAV however, we managed to make maps that were free of clouds, as we could choose the best time to fly, even on days with cloud cover.

… with satellite data, certain diagnoses are impossible to achieve at the exact time when they would be the most useful for the customer … images were only available after a 15-day wait

As a larger example, during the summer of 2017, we flew 13,000 hectares of soybean and corn fields, without even a single shadow of cloud! Our client was, of course, very happy. This result was thanks to our method of ‘cloud surfing’, a proprietary 21Sur procedure that allows us to map large areas when clouds are present. We alternate between waiting circuits, perform a basic analysis of information in the field and then add complementary flights only for specific areas where there was a cloud presence. This allowed us to achieve the following result:

Frustrated by the negative effect of cloud on the satellite imagery he purchased, Pablo and his team developed a unique ‘cloud surfing’ drone workflow with which to minimize this problem.

Last but not least, always put security first. It is essential to take care of the integrity of your UAV. This translates to the correct planning, to always having in mind your emergency procedures, and to never placing too much demand on the UAV’s capabilities.

I strrongly recommend having an Operations Book for each UAV you operate.

If the weather becomes severe and a planned mission becomes compromised, the ideal action is to return the drone to the ground control station, as we can always find the time to take off again and finish the mission.

An important tip from an experienced operator with over 1,000 UAV flights under his belt: track all your flights in an Operations Book so that you know how many hours are left before your next scheduled maintenance.

I also strongly recommend having an Operations Book for each UAV you operate. We do this, and it gives us the security of knowing how many hours our eBee has flown, how many hours are left before its next scheduled maintenance—we stipulate 100 hours between each—and it allows us to chart the performance of our equipment, documenting each flight situation, the batteries used on every mission, the remaining load percentages after landing, etc. This level of detail really allows us to control the status of our teams and to make informed maintenance or replacement decisions, which are vital to preserving the UAV’s integrity.

You mentioned agriculture and forestry being key focus industries for 21SUR Aerospace. Could you tell us a little more about types of flights you typically fly? What type of clients are you flying for, using what type of cameras, and with what goals and results?

In 2010, the only fixed-wing UAVs we had available came from military manufacturers and operating these systems was complex: we needed runways and we were usually flying at altitudes above 6,400 feet to conduct our survey missions, operating between five and ten kilometers away from the GCS. We gained a lot of experience doing this but when, in 2015, we met the eBee, this was I would describe as a big before and after moment for us.

We migrated from big to small drones, but we gained versatility and operational simplicity!

The challenge then was how to cover the largest areas possible with this little mapping drone. Once we realized we could do this with multiple drones at the same time we became much more efficient and improved our operations compared to with our previous large UAV—we migrated from big to small drones, but we gained versatility and operational simplicity!

While our company’s focus was traditionally on agriculture, the forestry sector has grown a lot and is now close to becoming our main customer segment. Uruguay’s main forestry companies rely on the quality of the UAV mapping we provide. They use the drone’s data as a regular input into their decision-making process, both for inventory management and in the planning of new forest fields.

The products that are the most demanded by forestry companies are false color orthomosaics (i.e. reflectance maps)—produced using the eBee Ag’s NIR camera—which in turn allow us to make NDVI index maps, digital terrain models and volume calculations (for example, we are currently working on calculating the volumes of piles of harvested trees).

Another service that has high demand is the counting of young trees and the preparation of plant density maps. The drone’s data products allow forestry companies to make new plantations in places where trees are missing or where there was a problem with their original planting, while the digital terrain model allows them to understand which areas are prone to flooding so that these are automatically excluded from their planting plan.

It’s because of this surgical targeting that we really feel we are contributing to the transformation of agriculture into an activity with less environmental impact

As for agriculture, we carry out most of our flight survey campaigns from December to March, which is a critical period for crops such as soybeans and corn. Each year, for customers such as agronomists and agricultural service companies, we map between 13,000 and 20,000 hectares of crops. Our flights are a very important input for these clients when conducting samplings, identifying different management zones, and detecting deficiencies early on.

When the weather isn’t ideal for flying, it is ideal for processing the data collected from previous flights, as in the case of these corn fields.

For example, this summer we prepared zoning maps showing crops of different vigor. These maps were then used to perform targeted foliar sampling, which saved time in the diagnosis and also allowed the application of agrochemicals in a more efficient, surgical and ultimately economic way, compared to traditional procedures. It’s because of this surgical targeting that we really feel we are contributing to the transformation of agriculture into an activity with less environmental impact.

What was the most interesting or eye-opening moment of the 1,000 flights you’ve completed—did anything unusual or unexpected happen that you learned from?

Yes. We used this amazing mapping tool at a time when I never would have thought we’d use it. It was a very personal and emotional experience.

We made our services available to the emergency services, since from the air we could make rapid assessments of the damage

In 2016, my hometown of Dolores, a city of just over 17,000 people, was destroyed by a huge tornado (EF4 on the improved Fujita scale). It really devastated the city. Buildings collapsed, vehicles were thrown in the air and, unfortunately, it caused the loss of human lives. We had never experienced something like this, so the emergency services were overwhelmed by their inability to quickly assess the damage—it seemed like a bomb had fallen in the center of the city.

Working with local, national and international organizations, Pablo’s team used an eBee to capture orthomosaics that helped assess the damage caused by a devastating tornado in Dolores, Uruguay in 2016.

We made our services available to the emergency services because from the air we could make a rapid assessment of the damage and direct the rescue teams to the affected areas.

Working with the National Emergency system (SINAE), The Red Cross, the Province Government (IMS) and in coordination with the Uruguayan Air Force (FAU), our mission was to map the entire affected part of the city, making RGB flights with a ground resolution of 8 cm per pixel, which could guarantee accurate visualization of the damage. This information was fundamental to accessing places that were impossible to access by land, in addition to checking the structures of tall buildings from above. This mission was the contribution to society that we feel most proud of, and where the eBee fulfilled the task it was entrusted with, with excellence.

That’s a wonderful use of the technology. So lastly Pablo, what advice would you give to other commercial drone operators that might help them reach 1,000 successful UAV flights too?

Good discipline on every flight is fundamental. Our flights begin, in fact, two days earlier with the planning of their technical, meteorological and regulatory aspects. The key is not to leave things to occur at random, to be well prepared for the “What if?”.

The key is not to leave things to occur at random, but to be prepared for the unexpected

Situational awareness during flight is also crucial to carrying out successful operations; taking into account that another user might unexpectedly appear in our airspace. We must have a plan for that and act efficiently to give way to the other user. We need to ensure we don’t generate any risk for manned aviation.

Thanks, Pablo – those are really valuable insights and congratulations again on your achievement!

Thanks, you’re welcome!


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