Guy Norris Atlanta

The shrinking capability for flight testing in the U.S.—the jewel in the crown that paved the way for the nation's leading role in global aerospace in the 20th century—is forcing NASA and Air Force planners into a major review aimed at halting the decline.

The action comes as the agency and USAF gird themselves for potential budget cuts that could further threaten existing flight-test capacity. It also follows in the wake of controversial findings from a National Research Council (NRC) report into the state of NASA flight research, the recommendations from which were aired to a broad industry group for the first time at the American Institute of Aeronautics and Astronautics Joint Propulsion Conference in Atlanta.

The growing shortfall in new test assets has been keenly felt by NASA, which has not sponsored a major X-plane for seven years and has seen recent efforts to develop a larger, piloted X-plane rejected on budget grounds. At the same time, even funding for more affordable, small-scale unmanned experimental aircraft has become tighter as pressure grows to trim NASA's already reduced aeronautics allocation.

One solution being studied by the Air Force Research Laboratory (AFRL) to partially cover the gap includes closer collaboration with NASA and the FAA on potential joint flight-test efforts to explore energy-efficient technologies. The search for lower fuel burn is a common goal for commercial and defense communities, and is a top priority for the Pentagon, which wants to dramatically reduce energy consumption across the services. AFRL is keen to study potential flight-test efforts for technology, which could particularly target the Air Force's current use of 2.4 billion gal. of fuel per year. Of this, 64% is consumed by the air mobility fleet, which could be a prime candidate to use the same fuel-saving technology being studied by NASA and the FAA.

William Harrison, AFRL technical adviser for fuels and energy, says the approach includes “formulating an AFRL, NASA, FAA portfolio to divide and conquer, and we've been doing that over the past year.” The scheme includes taking technologies such as laminar flow, low-cost composite structures, advanced engine cycles and alternate fuels, and funneling them into testbed aircraft or applying them to future upgrades.

“There's maybe an opportunity to re-wing and reengine an existing legacy transport aircraft and use that as a demonstrator,” says Harrison. Although no specific aircraft is identified, the most likely candidate for the project is believed to be a Boeing C-17 in the 2017-19 timeframe. The concept is even more intriguing, given that the C-17 fleet is now the largest single consumer of fuel in the Air Force and will be ripe for a life extension until the advent of a C-X family of replacements in the late 2020s or beyond.