Harnessing recreational drones to enhance diver safety
When a diver goes missing, the sea becomes a vast, indifferent expanse, turning a rescue effort into a race against time. Every second matters, and the right tools can make the difference between a successful rescue and a tragic recovery.
Traditional search protocols often assume the missing diver is afloat, aided by their buoyancy control device (BCD), and limit the search to the surface. Divers may remain submerged, however, adding a critical dimension to the search effort.
Recreational drones (RDs) can be effective supplementary tools as part of emergency action plans (EAPs) for locating missing divers at or near the surface.
Challenges of Locating a Missing Diver
Searching for a missing diver can be costly and logistically complex. The initial response typically involves small vessels, such as dive boats or tenders, with limited visual coverage and speed. Aircraft can offer a broader visual range but come with high costs and delays. Most dive sites are far from airstrips, and organizing aerial support often takes precious time.
Recreational drones are emerging as a promising, cost-effective, and rapidly deployable option to complement existing search efforts and protocols. They offer a unique combination of features that make them a valuable addition to any dive vessel’s safety kit.
Drone Advantages
RDs have great potential for search and rescue (SAR) missions for many reasons. These devices are relatively affordable, with basic recreational kits costing around $1,300 for a drone with three long-lasting batteries and excellent range. The range is often more than 9 miles (14 kilometers), with a battery life of up to 45 minutes in ideal conditions.
Drones also boast impressive speed capabilities. With top speeds of more than 35 miles per hour (56 km/h) and average speeds of up to 22 mph (35 km/h), they can be an excellent searchtool.
A conservative estimate allows for 35 minutes of effective operation. Spending half of that time in a linear back-and-forth search pattern, the drone could cover a linear distance of about 7.8 miles (12.6 km). When multiplied by an average 262-foot (80-meter) visual width, this distance results in a total surveyed area of about 0.4 square miles (1 square km).
These figures highlight the strong operational potential of drones in SAR missions, especially in marine and coastal environments where speed and area coverage are critical to success. These characteristics allow drones to rapidly scan large areas — an essential requirement in emergencies.
A stationary search can be particularly effective when dealing with strong wind gusts that could compromise drone stability or when battery levels are running low, limiting the ability to continue forward. In such cases, gaining altitude allows the drone to conserve energy while expanding its visual coverage. The higher the drone flies, the larger the area it can scan without moving.
This capability can be crucial when battling wind conditions or planning a return flight to base. But this benefit comes with a trade-off. As altitude increases, the apparent size of objects in the drone’s camera feed decreases, making a diver more difficult to detect, especially in challenging sea conditions or low-contrast environments. This trade-off is important to consider when planning a drone-assisted search strategy. Balancing altitude, coverage, and visibility will improve the likelihood of detection while preserving battery life and operational effectiveness. By understanding this relationship you can determine the optimal altitude at which your drone will provide the best balance of coverage area and detection capability. This strategic choice maximizes your chances of locating a missing diver.
Many recreational drones include software that allows pilots to predefine flight paths using waypoints on a map. This feature is especially valuable during a search operation, as it enables the drone to systematically scan large areas with minimal manual control, reducing pilot fatigue and human error.
Preprogrammed paths (such as parallel lines or a grid) ensure a consistent search pattern, improving coverage efficiency, minimizing the risk of unchecked areas, and avoiding overlaps. Additionally, programmable routes can account for environmental factors such as wind direction, wave movement, or sunlight reflection that might interfere with visibility. Once the pilot has set the path, they can focus on real-time image analysis, enhancing the search effectiveness.
Operational Considerations
While drones are powerful tools for extending visual range during search operations, their effectiveness is subject to several operational and environmental factors. Some crucial considerations and recommendations will enhance their use in maritime settings.
Weather conditions: Visibility, wind direction, wind speed, and overall weather can significantly affect drone performance. Conduct flights only in favorable weather conditions and within the equipment’s operational limits.
Optical limitations: Elements such as glare on the water, surface waves, or limited camera resolution can hinder the detection of objects or people. Thermal sensors or high-resolution cameras can help overcome some of these constraints. Neutral density or polarized filters can help reduce glare.
Screen size: Most drone controllers have displays no larger than a smartphone, which limits the search effort to a single operator. A larger screen or a feed to an external display allows multiple observers and improves the chances of spotting a missing diver.
Display visibility in bright sunlight: Screen glare and limited brightness can be challenging when operating a drone under intense sunlight. Moving inside a vessel’s cabin may reduce screen reflection but can limit the drone’s operational range. Possible solutions include using a commercially available sun hood, improvising a shade, or using first-person view goggles.
While drones have inherent limitations — such as limited battery life, vulnerability to adverse weather, and reliance on pilot expertise — strategic planning and informed decision-making can help mitigate them. In remote areas where traditional resources may be scarce, drones offer a cost-effective solution that greatly enhances search and rescue capabilities.
Technology alone is not enough, however. Anticipating weather conditions, understanding wind and current patterns, and recognizing how coastal topography influences search efficiency are critical factors. Consulting with local maritime authorities or coast guards can provide valuable insights into seasonal conditions and improve the likelihood of locating a missing diver.
By combining EAPs, advanced tools, local expertise, and comprehensive training, we can transform the challenges of oceanic SAR operations into manageable opportunities. Every step forward brings us closer to a future where no diver is left behind.
A drone should complement, not replace, other resources such as boats, dive equipment, helicopters, and communication systems. The drone is a spotter and locator and can’t do rescue or recovery. The operation’s success depends on activating all aspects of the EAP and having experience with drone use. Pilots should be certified and familiar with search and rescue protocols, and the rescue team should train and practice protocols for spotting divers on the screen using different controlled conditions.
While drones may not completely replace conventional search methods, their versatility, affordability, and rapid deployment make them invaluable assets. By leveraging technology, we can enhance safety, expedite response times, and save more lives.
Explore More
Find more about Drones and dive safety in this bonus video.
© Alert Diver – Q3 2025