DARPA Progresses on Active Flow Control Based FX-Plane Design

DARPA has selected three contractors to work on the Control of Revolutionary Aircraft with Novel Effectors (CRANE) program, which aims to demonstrate an FX-aircraft design based on active flow control (AFC).

The goal is to demonstrate significant efficiency benefits of AFC, as well as improvements in aircraft cost, weight, performance, and reliability.

The term AFC has described a wide range of fluid dynamic control approaches. For the CRANE program, active flow control is defined as the on-demand addition of energy into a boundary layer for maintaining, recovering, or improving vehicle aerodynamic performance.

“AFC has been explored at a component level, but not as an integral piece of aircraft design. By altering the design approach, CRANE seeks to maximize the chance of a successful X-plane development while also integrating AFC into the aircraft’s stability and control,” said Alexander Walan, the program manager for CRANE in DARPA’s Tactical Technology Office.

The program is kicking off Phase 0, a long conceptual design phase to give the contractors - Aurora Flight Sciences; Lockheed Martin; and Georgia Tech Research - time to evaluate flow control options before solidifying their demonstration approaches.

Phase 0 awards will comprise multiple conceptual design trades, active flow control component testing, multi-domain analysis and optimization, concept down selection, and a conceptual design review.

CRANE is excluding already proven techniques that use large external moving surfaces, mechanical vectoring of engine jet exhaust, or other traditional moving aerodynamic control devices.

 “Active flow control technology has matured at the component level to the point where a potential leap forward in aircraft technology is possible,” said Walan. “We see an opportunity with CRANE to open up the future design space for both defense and civilian applications.”

The X-planes are a series of experimental United States aircraft and rockets, used to test and evaluate new technologies and aerodynamic concepts. They have an X designator within the US system of aircraft designations, which denotes the experimental research mission.