In 1908, just five years after the Wright Brothers took their first flight; an Italian captain named Cesare Tardivo took the first aerial photographs from a plane for mapping purposes. Since that time, fixed-wing airplanes have become the primary method of acquiring aerial photography. With the advent of Unmanned Aerial Vehicles (UAV), alternative methods of capturing aerial photographs and topographic mapping have emerged.
UAVs have been used for military applications as far back as World War II, but commercial mapping applications have only taken hold in the last few years. The number of commercial permits approved by the Federal Aviation Administration (FAA) has increased from just 2 in 2014 to over 3,100 in 2016. What does the emergence of UAVs offer the mapping industry that airplanes do not provide?
Fixed-wing airplanes fly thousands of feet above their target, while UAVs fly just hundreds of feet above the ground. Airplanes must contend with low cloud coverage, which can delay mapping missions for considerable lengths of time. Since UAVs can usually fly below the cloud level, they can perform a mission at any time, regardless of cloud coverage.
Flying at a lower altitude also means UAVs can use an inexpensive camera and usually provide better resolution imagery than fixed-wing airplanes. The cameras used by airplanes can cost upwards of 2 million dollars while a typical UAV camera will cost around $1,000. Aside from camera differences, the initial cost of an airplane easily exceeds the cost of UAV technology. The UAV counterpart can cost between $15,000 and $50,000 dollars.
These lower costs can allow UAV operators to provide the same outputs as airplanes at a more economical price for their customers. Case studies comparing UAV product prices to airplanes indicate that UAV outputs tends to be less expensive.
Time can also be an important factor when comparing aerial mapping services. Mapping using conventional services typically requires substantial forward planning. It can take weeks to schedule a flight and then additional weeks to complete the mapping process. In some cases, UAVs can be dispatched on the same day with post-processing completed and delivered overnight. However, UAVs have limitations of their own.
UAVs are small and lightweight and unlike airplanes. Most cannot fly in winds over 30 mph. They can also be affected by predatory or territorial bird strikes which can cause thousands of dollars worth of damage. Another limitation for UAVs is short battery life, which typically ranges from 15 minutes to one hour. This time frame only allows the UAV to cover 50 to 150 acres per flight, while an airplanes can usually cover thousands of acres in a single flight. As a result, airplanes are generally more effective for completing large-scale mapping assignments and don't have to contend with wildlife or moderate winds.
The use of UAVs for mapping services is still in its infancy and many innovations have yet to come. Increased battery life, obstacles avoidance, and solar powered UAV's may close the capability gap between airplanes and UAVs. At this time. UAVs are best suited for smaller mapping missions covering hundreds of acres, as opposed to thousands. Airplanes, on the other hand, remain better suited for larger missions since longer flight time capabilities allow them to take advantage of economies of scale. In conclusion, the UAV will provide a cost-effective and quicker solution for small-scale aerial mapping compared to traditional fixed-wing airplane.