Nations bordering the South China Sea are increasingly turning to long-endurance drones to maintain constant surveillance across the strategically important waterway, overcoming the limits of traditional aircraft and naval patrols. At the request of Manila, the US Marine Corps recently positioned MQ-9A Reaper drones in the Philippines to bolster shared maritime domain awareness and reinforce regional security. According to US Marine Corps Forces, Pacific, the aircraft are unarmed and used exclusively for intelligence, surveillance, and reconnaissance.
US officials described the temporary deployment as a sign of mutual commitment to safeguarding open and secure sea lanes throughout the Indo-Pacific. The MQ-9A, first introduced in 2001, is equipped with sophisticated sensors, can fly for more than 27 hours, and reaches altitudes of up to 15,240 metres (50,000 feet). Its payload capacity of 1,746kg enables mission flexibility ranging from search-and-rescue to precision targeting.
The move followed a visit by Pentagon chief Pete Hegseth to Kuala Lumpur, where he urged defence ministers from the Association of Southeast Asian Nations to deepen maritime cooperation. His proposal included the development of joint programmes for unmanned aerial and underwater systems that could enhance surveillance while reducing operational risks and expenses.
Drone usage across the region is no longer limited to countries with direct territorial claims. Collin Koh, senior fellow at the S. Rajaratnam School of International Studies in Singapore, noted that a wide range of regional and extra-regional actors now employ unmanned platforms in the air, on the surface, and underwater.
China, a global leader in unmanned technology, has invested heavily in extending drone endurance to support continuous patrols over the South China Sea. A Chinese defence industry report highlighted that the People's Liberation Army Navy accelerated drone development to address the endurance limitations of crewed fighter jets. The Wing Loong-2, for example, can fly for up to 32 hours depending on its payload configuration.
Chang Yen-chiang of Dalian Maritime University said China relies on unmanned aircraft and vessels for routine patrols around contested areas such as Scarborough Shoal. The shoal, located roughly 220km west of Luzon, has been under Beijings control since 2012 and remains a flashpoint in China-Philippines maritime disputes. Because Chinas nearest major base is around 600km away, drones offer a more efficient way to maintain round-the-clock monitoring when coordinated with coastguard ships and manned aircraft.
Recent activity around Scarborough Shoal underscored the role of unmanned systems. On November 20, the USS George Washington strike group arrived near the area, coinciding with sightings of a Chinese Wing Loong-10 drone a jet-powered model with limited stealth features detected by satellite tracking data.
The Philippines is not alone in expanding drone capabilities. Vietnam has pursued its own long-endurance programmes since the mid-2010s, including the HS-6L, which can stay aloft for up to 35 hours and is believed to have been developed with Belarusian assistance. Vietnamese defence firm Viettel recently unveiled the VU-MALE, a multi-role drone equipped for precision missions in varied weather conditions.
Indonesia received its first Turkish-built Anka-S drones in September as part of a US$300 million agreement for 12 units, which includes training and technology transfer. Malaysia is scheduled to deploy three Anka-S drones early next year at Labuan Air Base to strengthen surveillance over its exclusive economic zone.
Koh noted that capabilities vary widely among South China Sea actors. Countries with greater resources, such as China and the United States, field a broader range of unmanned assets, while others operate within more limited technological and financial boundaries. Even so, the continuous presence and lower cost of unmanned systems can deliver tangible strategic advantages reinforcing territorial claims in peacetime or helping neutralise threats with reduced risk during conflict.
However, experts warn that drones are not a substitute for human presence. Analyst Zak Kallenborn of the Centre for Strategic and International Studies stated that unmanned aircraft are useful for monitoring behaviour at sea but cannot physically assert control. Effective response still depends on how states integrate drone-collected data with human decision-making and direct intervention.
Koh added that advanced unmanned operations require specialised personnel and secure infrastructure capable of withstanding electronic interference. For many Southeast Asian states with limited defence budgets, such requirements pose significant challenges as they consider expanding drone fleets to support their maritime claims.
