The Model 437 Vanguard was originally conceived as an unmanned loyal wingman concept in 2021, designed to operate alongside crewed aircraft in attritable roles. Renderings at the time depicted an uncrewed platform with a range of around 3,000 nautical miles, a cruise speed near Mach 0.8, and payload options including AIM-120 AMRAAMs or side-looking radar systems.

Its first flight in August 2024 revealed a cockpit, making the Vanguard an optionally piloted aircraft. As we reported on that occasion, the Vanguard is powered by a single Pratt & Whitney PW535 turbofan engine producing 3,400 pounds of thrust, and features a wingspan of 41 ft (12.5 m), gross takeoff weight of 10,000 lb (4,536 kg), and endurance of six hours.

Northrop Grumman contributed to the program through its Digital Pathfinder initiative, using advanced digital engineering methods to design and build the Model 437’s wings. The process, the company said, reduced rework to less than one percent compared to the 15–20% typical of conventional design programs, drawing directly on lessons from the B-21 Raider stealth bomber program.

The Model 437 Vanguard resumed flight testing at Mojave Air and Space Port, , announced by Scaled Composites on Sep. 20, 2025, comes after extensive modifications to the airframe for its new role since its first flight in August 2024.

The company reported updates to the hydraulic system, cockpit integration of new pilot interfaces, and the incorporation of autonomy subsystems developed by Northrop Grumman for Beacon. These upgrades pave the way for the Model 437 to serve as a versatile airborne platform for experimentation with autonomy and artificial intelligence-driven mission software.

“We had the challenge of taking an airplane that has only flown once and converting it into a versatile autonomous testbed, which demonstrates Scaled’s agility and flexibility in achieving new test objectives,” said project engineer Yuto Shinagawa, highlighting the integration of flight safety protections for autonomous operations. As an example, he mentioned the introduction of protections in the flight control system to assure flight safety when engaging the autonomous system.

As Scaled Composites resumes envelope expansion flights, the focus will be on validating the integration of Beacon’s autonomy ecosystem and ensuring safe transitions between crewed and autonomous modes. The aircraft’s optional manned capability allows safety pilots to supervise tests while gradually handing over control to autonomy software, reducing risks in early phases.