On Monday, April 20, 2026, during the Sea-Air-Space exposition in National Harbor, U.S. companies Lockheed Martin and Saildrone presented a new line of Spectre-class unmanned surface vehicles (USVs): the Spectre Silent Endurance, with its distinctive sail (or rather rigid aerodynamic wing) and the Spectre Stealth Strike, without it.
Image: Saildrone
At 52 meters (170 feet) long, with a displacement of 250 tons and a speed of up to 30 knots, Spectre is an ultra-endurance USV designed to carry out multiple missions above and below the surface of the oceans. The Spectre design was developed from the keel up to provide long range, quiet operation, and extended endurance, drawing on more than 10 years of Saildrone’s experience operating ultra-endurance USVs in the world’s harshest conditions. Smaller models had previously been offered: Explorer and Surveyor. The latter is to be integrated with the JAGM Quad Launcher for four AGM-179 JAGM anti-tank guided missiles, which will be demonstrated during the upcoming RIMPAC 2026 exercises.
A distinctive feature of Saildrone vehicles is a rigid aerodynamic wing sail resembling a sail, which generates lift like an aircraft wing. The wing is actively controlled by AI, which rotates it, changes its angle of attack, and adjusts it to the wind to maximize efficiency. In addition, photovoltaic panels on the wing and hull charge batteries for the vehicle’s sensor, communications, and control systems. The latest Spectre vehicles, however, are to be offered in two variants: with and without the wing.
Spectre is to reach speeds of up to 12 knots, compared with 8–12 knots for its predecessors, and then start its 5,000-hp Caterpillar diesel engines to accelerate to 27 knots with full fuel tanks and a 25-ton payload. At a cruising speed of 25 knots with that payload, Spectre is to have a range of 3,280 nautical miles in calm water and 2,790 nautical miles in sea state 4. Variable-pitch propellers enable efficient operation across the full speed range, reduced acoustic signatures, and almost silent operation at low speed during missions involving the towing of antennas or variable-depth sonar systems, for example.
A concealed deck provides space for containerized payloads, from two 40-foot (12.7-meter) containers to five 20-foot (6.3-meter) containers, or various mixed configurations. This unique configuration, close to the waterline, enables easy loading through the transom, while the bulwarks protect the payloads from prying eyes and from the relentless sea spray that becomes especially intense at high speeds in difficult weather conditions. Spectre’s maximum payload exceeds 70 tons.
Spectre is available in two variants, depending on customer requirements:
- Spectre Silent Endurance, with the Saildrone wing, offers increased range and endurance, the ability to integrate sensors high above the waterline, and the ability to return to its launch point on missions covering more than 8,000 nautical miles. Its hybrid propulsion system, enabling near-silent cruising at speeds of up to 12 knots, is optimized for anti-submarine warfare support missions and other missions requiring reduced acoustic signatures.
- Spectre Stealth Strike, using a wingless configuration, maximizes speed and minimizes visual and radar signatures. Its lower profile is ideal for operations in which speed, visibility, and signature affect mission performance. From the outset, Spectre was designed to operate without the wing in strike missions requiring higher speed and stealth operations in low-visibility conditions.
The performance of the Spectre architecture has been verified and tested in the Force Technology tank in Copenhagen, Denmark – the hydrodynamic equivalent of a wind tunnel. Several months of testing and development of a 1:7-scale model made it possible to verify power and seaworthiness requirements up to full speed in sea state 5. Only through careful physical testing can CFD calculations be verified and propulsion systems optimized to ensure guaranteed full-scale performance.
Going beyond traditional intelligence, surveillance, and reconnaissance (ISR) roles, Spectre was designed to carry mission-tailored effects needed by commanders. To provide these capabilities, Saildrone and Lockheed Martin will integrate numerous payloads under a strategic partnership worth 50 million USD, signed in October 2025. These include the Mark 70 Mod 1 Payload Delivery System, based on the shipborne Mark 41 VLS, for various types of missiles; active and passive anti-submarine warfare suites, such as the TB-29 towed array; electronic warfare systems; and the CAPTAS-4 Combined Active Passive Towed Array Sonar variable-depth sonar system from France’s Thales group.
Introducing Saildrone Spectre: Today at Sea Air Space, Saildrone introduced our largest and most capable platform to date: At 52 m, Saildrone Spectre is a modern, stealth-optimized USV designed for demanding, long-duration defense missions.
Read more: https://t.co/is9KRmP0CM pic.twitter.com/dVDkqbkZtK
— Saildrone (@saildrone) April 20, 2026
A new class of unmanned surface vehicle—the @Saildrone Spectre—was unveiled for the first time this week.
In partnership with Saildrone, we'll integrate numerous payloads onto Spectre, providing persistent, flexible maritime capability in contested environments. #SAS2026 pic.twitter.com/kv2pCVKS6g
— Lockheed Martin (@LockheedMartin) April 21, 2026