In Lyon, an underground drone was the key to assessing a mysterious sinkhole that had appeared in a residential area. The Elios 3 played a crucial role in providing vital information quickly and safely.

Key Benefits at a Glance

Lyon has a rich history dating back to its founding as Lugdunum in 43 BC. Today, the city is known for its Roman landmarks like the Théâtres Romains de Fourvière and the Jardin Archéologique. However, beneath the surface lie ancient structures such as old sewers and storage areas. These can sometimes cause unexpected geological issues, like sinkholes, which require careful monitoring to ensure public safety.

Local Authorities Turn to Drone Technology for Emergency Response

In a recent incident, a large hole suddenly appeared near an apartment building in Lyon. The Lyon Metropole quickly recognized the potential danger—especially given the presence of Roman ruins below. If the hole expanded, it could threaten the stability of the building above and endanger nearby residents.

The sinkhole was close to a residential building, raising concerns about its size and impact.

Xenodrone, a company specializing in drone inspections, was called in to assess the situation. Julien Gay, the head of Xenodrone, had experience in emergency response and understood the urgency of the task. He knew the Elios 3, designed specifically for underground operations, was the best tool to gather the necessary data quickly and safely.

Using an Underground Drone to Respond to Land Subsidence

Upon arriving at the site, Julien found a sinkhole just 2.5 meters away from the building’s wall. Given the history of similar incidents nearby, he suspected the presence of ancient Roman structures beneath the ground. Without a drone, it would have been nearly impossible to explore the cavity safely or determine its depth and activity level.

The Elios 3 entered the sinkhole without putting anyone at risk.

Julien needed to check if the sinkhole was expanding and whether it threatened the building's foundation. Using the Elios 3’s LiDAR technology, he conducted a fast and detailed scan. In just four minutes, the drone captured enough data to create a 3D model of the underground space.

Analyzing Subsidence with an Underground Drone

After collecting the LiDAR data, Julien returned to his office and used Inspector 5 to generate a report for the local authorities. The scan revealed a large cavity extending six meters deep. This information was essential in determining the risk to nearby structures and guiding further action.

The data helped responders understand how close the cavern was to the building’s foundations.

The visual data also provided insight into what lay inside the sinkhole—whether it was a natural formation or a remnant of ancient Roman construction. This information was crucial for making informed decisions about stabilizing the area.

The Flexibility of the Elios 3 Enhances Emergency Response

When time is critical, the Elios 3 proves to be an invaluable asset. A short flight was all it took to gather data that would have otherwise been unreachable. More importantly, it ensured the safety of the team on the ground by eliminating the need to approach the sinkhole directly.

Julien shared his thoughts on the mission: “As a former firefighter, I know how important speed and precision are in emergencies. Now, with the Elios 3, we can respond faster and more effectively. It’s not just about inspections—it’s about saving lives.”

Following this mission, the local authorities discovered a hidden spring beneath the sinkhole. They filled it with 63 cubic meters of material to stabilize the ground. Now, they have a clear understanding of the situation and can monitor future changes using the data collected by the Elios 3.

This case highlights the growing importance of drones in emergency response. With their ability to access dangerous areas quickly and provide accurate data, they are becoming an essential tool for modern disaster management and urban safety.