Aurora Advances DARPA Vertical Takeoff X-plane to Next Development Phase

Aurora Flight Sciences has completed the conceptual design of an experimental vertical-takeoff-and-landing (VTOL) aircraft for the Pentagon and is transitioning to the next phase. On 20^th May, the company announced that its blended-wing design for the SPRINT (Speed and Runway Independent Technologies) program will now enter the preliminary design stage.

The Defense Advanced Research Projects Agency (DARPA) aims for its SPRINT vertical takeoff aircraft, known as the X-plane, to achieve speeds between 400 and 450 knots, significantly outpacing the V-22 Osprey's top speed of 270 knots. According to a DARPA official speaking to Defense News in December 2023, SPRINT must also be capable of stable hovering, smooth transition from hover to forward flight, and incorporate a distributed energy system to efficiently power all propulsion technologies during that transition. DARPA is allowing companies the flexibility to decide whether their aircraft will be crewed, uncrewed, or capable of autonomous flight.

In November 2023, DARPA provided six-month contracts to four companies to initiate their conceptual design work. These companies are Aurora, which is a subsidiary of Boeing, Bell Textron, Northrop Grumman, and Piasecki Aircraft Corp. Each company received this contract to begin developing their initial design concepts for the project.

On April 30, DARPA gave Aurora an additional $25 million to continue working on its version of the SPRINT program, building on the earlier funding of $4.2 million. With this new contract modification, Aurora is now the only company to receive extra funding to move forward in the SPRINT program. However, DARPA may still award more contracts to other companies in the future. Back in December, DARPA had announced that it plans to eliminate at least one of the four companies involved in the competition after they complete the conceptual design phase. The agency chose not to comment on whether there would be any more SPRINT contract awards.

Aurora’s blended-wing aircraft design incorporates three embedded lift fans for vertical flight, which then transition to embedded engines for forward flight. This design aims to reduce drag, enabling high-speed travel, and is ideal for air mobility and special operations missions, according to the company. Aurora released new concept art revealing that the aircraft will be uncrewed and feature a composite exterior. The aircraft is projected to achieve a cruise speed of 450 knots.

Aurora has announced that it has the capability to integrate additional lift fans into its fan-in-wing design if the military's requirements were to change. Additionally, the company can create a crewed version utilizing the same fan technology. The SPRINT team at Aurora has set a goal to finish the preliminary design review within a year and is aiming for a first flight within three years. On the other hand, Bell is taking a different route for the SPRINT program. Concept art released by Bell in November 2023 showcases their approach, which features a tiltrotor design. This design is reminiscent of the traditional Osprey aircraft, highlighting Bell's distinct strategy compared to Aurora's fan-in-wing design. While Aurora focuses on versatility and adaptability with potential modifications to their existing design, Bell is leveraging a more conventional tiltrotor configuration for their SPRINT project.

Earlier this month, DARPA awarded Aurora an $8.3 million contract modification to continue designing the Liberty Lifter, an experimental heavy cargo seaplane.