Aurora Shows Very High-Speed, Vertical Lift Concept Design

Aurora Flight Sciences on Oct. 8 unveiled new details of a notional operational variant of the fan-in-wing concept it is proposing for a high-speed, vertical-takeoff-and-landing (VTOL) X-Plane.

The operational version of the Boeing-owned company’s candidate for a DARPA demonstrator program would boast nearly the same wingspan and payload weight of a Lockheed Martin C-130J, yet fly up to 90 kt. faster and be able to take off and land vertically like a helicopter.

The Aurora concept includes two turbofan engines for horizontal thrust and four fans embedded into the blended wing body airframe for vertical lift. This “vision” aircraft concept also features cranked outboard wing sections and no vertical tails.

The concept depends on a successful Aurora bid to develop the demonstrator for DARPA’s Speed and Runway Independent Technologies (Sprint). Bell is working on a competing proposal based on a tiltrotor aircraft featuring stop-fold rotor technology.

Both companies received contracts in May 2025 to complete preliminary design reviews in April 2025. The agency will then decide whether to move forward with building an X-plane and launching a flight test campaign in 2027.

Aurora’s one-third-scaled prototype calls for a tailed, blended wing body design, with the trailing edge of the wing positioned forward of the fuselage tail. The 45-ft. wingspan includes three lift fans. The top of the fuselage includes two auxiliary inlet doors for airflow in vertical mode. A pair of caret-shaped inlets on either side of the forward fuselage ingests air for a single turbofan engine to provide horizontal thrust. The prototype is being designed to carry a 1,000-lb. payload.

DARPA’s goal is to achieve a new standard in high-speed flight for a transport aircraft with VTOL capabilities. The U.S. Army’s Future Long Range Assault Aircraft plans to field a Bell tiltrotor in 2031 with a forward speed of at least 300 kt. The Sprint program aims to increase that top speed by as much as 50%, to 450 kt.

By using that speed and vertical lift capability, the operational version of the Sprint prototype could present an attractive option for replacing the Bell Boeing CV-22 and Sikorsky HH-60W fleets.

“High-speed, stealth, runway-independent transport could help keep warfighters safe and effective in contested environments, so no domain is out of reach for our U.S. military,” Aurora CEO Mike Caimona said.

But the concept must first overcome the obstacles that have plagued development of high-speed, vertical-lift designs, including previous efforts to develop fan-in-wing aircraft, including the Ryan XV-5.

DARPA and program supporters believe that a combination of modern advances in lightweight structures and fly-by-wire flight controls could make such high-speed, runway-independent aircraft viable again. A fan-in-wing design still faces the complexity of achieving a stable hover with a heavy aircraft over unprepared landing sites using multiple lift fans. Aurora’s operational concept calls for a design with a 130-ft. wingspan and a 30,000-lb. payload.

Aurora completed the first of three feasibility tests for the fan-in-wing technology earlier this year. A 4.6-ft. wingspan model equipped with three lift fans produced negligible downwash effects, the company says. Stability and control testing will follow in a wind tunnel later this year and early next year, using a 9-ft. wingspan model. Aurora also plans to test a 5/14-ft. semi-span model that includes an embedded lift fan to check for aerodynamic effects.