Compared with traditional space- and airborne remote sensing platforms, unmanned aerial vehicles (UAVs) offer sub-cloud imaging, portability, and strong environmental adaptability, enabling rapid deployment to severely affected areas to obtain macro-scale spatial distributions of damage. Earthquakes such as the 2008 Wenchuan Mw8.0, the 2013 Lushan Mw7.0, and the 2014 Ludian Mw6.5 illustrate the growing role of UAVs in post-earthquake emergency response. In the 5 September 2022 Luding Mw6.8 event, new vertical takeoff and landing (VTOL) UAVs further improved adaptability to harsh disaster-area environments and, when combined with multiple payloads, supported updated operational approaches for UAV-based earthquake response.
VTOL UAVs broaden emergency airspace access
Traditional long-endurance fixed-wing UAVs require relatively large clear areas to take off, circle, and climb, which limits their use in severely damaged areas where terrain and access are often compromised. VTOL designs that combine rotors and fixed wings change that operational constraint: UAVs can climb vertically to a safe altitude, transition to fixed-wing mode for cruise, and perform vertical landings at return points. This capability reduces takeoff and landing site requirements and allows faster coverage of targeted airspace in initial post-quake response.
For example, in the 5 September 2022 Luding Mw6.8 earthquake, the disaster area was concentrated in Luding County and Shimian County, where steep terrain and frequent geohazards disrupted road access and complicated situational awareness. China-developed Zongheng Dapeng UAVs entered the disaster area on the same day and began rapid damage mapping tasks. Their flexible takeoff and landing modes enabled emergency mapping of areas near Detuo Town and Moxi Town within two days, providing information support for rescue operations.
Multi-payloads enhance command and control capabilities
Long-endurance UAVs equipped with optical CCD sensors can rapidly map the spatial distribution of damage across the disaster area. Orthophotos, 3D models, and other derived products enable accurate assessment of building damage, seismic geological hazards, and critical lifeline infrastructure, supporting a unified map for emergency decision-making. Meanwhile, UAV-mounted electro-optical gimbals provide real-time dynamic imagery of key locations, streamed back to command centers to support rescue decisions. For example, on 7 September 2022, the field command center used UAV video monitoring to observe two rivers and adjacent slopes in Moxi Town, streaming live footage to support rescue coordination. From 8 to 12 September, a power emergency response team inspected transmission lines in the more severely affected Shimian County to maintain power lifelines. In addition, UAV-mounted LiDAR can obtain high-precision terrain information, supplying high-resolution 3D scene data for operational planning.
High-resolution imagery improves damage identification accuracy
Rapidly acquired post-earthquake UAV imagery enables extraction of high-precision damage information. By identifying damage features, establishing feature rule sets, and setting thresholds, it is possible to achieve accurate recognition, classification, and extraction of earthquake damage themes to support loss assessment. Visual interpretation indicated that buildings in Moxi Town, closest to the epicenter, suffered severe damage and that secondary slope failures were widespread. Around Detuo Town, building density was lower and damage lighter compared with areas near the epicenter, but secondary hazards were distributed widely along the Dadu River basin. Combining field surveys with UAV-derived observations to analyze building types and seismic resilience provides important support for scientific post-earthquake investigation and reconstruction planning.
Conclusion
VTOL long-endurance UAVs expand the spatial reach of post-earthquake emergency response. Their multi-sensor payloads provide real-time, multi-source decision support for on-site command and control. UAV-derived orthophotos and other emergency mapping products form an important basis for rapid post-earthquake damage assessment. As emergency response systems evolve, UAVs are expected to play an increasingly important role in earthquake emergency operations.
