Aurora Flight Sciences is progressing through Phase 1B of the Liberty Lifter program, the Defense Advanced Research Projects Agency (DARPA) program that seeks to develop, construct, launch, and operate a cost-effective X-plane that showcases groundbreaking heavy-air-lift capability from the sea.
To achieve this groundbreaking capability, the vehicle will operate efficiently in ground effect at high sea states and demonstrate cost-effectiveness using low-cost manufacturing and unique design features.
DARPA has been developing the Liberty Lifter since 2022. The goal of the project is to create a seaplane that is affordable yet has the cargo volume of a C-17 Globemaster III transport aircraft. The Liberty Lifter is designed to carry 100 tons of cargo and has a ferry range of 6,500 nm (7,500 miles, 12,000 km).
The end goal of Phase 1B is preliminary design, and a major focus during the phase is testing for risk reduction. ReconCraft, an Oregon-based shipyard, is also a team member of Aurora Flight Sciences and is providing expertise in maritime manufacturing methods. The company will build full-scale structural test articles, including a portion of the fuselage, to reduce risk and ensure quality as the team works with novel materials and unique requirements.
The Aurora team also tested a scale model of the hull in the tow tank at Virginia Tech, which offers a unique capability to study the slamming of craft during landing. The upcoming testing includes flying sensors and software for wave detection and prediction, which feeds the X-plane’s advanced control system for safely flying in ground effect over high sea states.
In its latest iteration, Aurora’s design for the Liberty Lifter changed from a t-tail to a pi-tail, which is more structurally efficient when accommodating an aft cargo door. Additionally, the relocation of the floats from the side spots to the vehicle’s wing tips creates a better balance between vehicle affordability and performance in the ground effect.
The Aurora-led team includes leading naval architecture and marine engineering company Gibbs & Cox, a Leidos company. Gibbs & Cox, being a leading naval architecture and marine engineering company, plays a critical role in the project since the X-plane is, in many ways, a boat that flies.
The team also benefits from the expertise of several advisors and engineers from Aurora’s parent company, Boeing. The program builds upon previous research and development by Boeing, which has a long history in seaplanes and flying boats.
“Innovations often occur at intersections. Here, it’s the intersection of our maritime and aerospace teams,” said Dan Campbell, Aurora program manager. “For example, the intersection of maritime manufacturing with aerospace structural design, or the intersection of maritime wave forecasting with aerospace controls.”
Phase 1B concludes with a preliminary design review, tentatively scheduled for January 2025. If the program progresses, flight testing will occur in 2028.