SHREVEPORT, LA - NASA researchers, working with Boeing's ecoDemonstrator Program, are testing non-stick wing coatings designed to minimize insect residue and help reduce aircraft fuel consumption.
The Boeing ecoDemonstrator 757 flight test airplane is at the Shreveport Regional Airport for testing. During 15 planned ecoDemonstrator flights in Shreveport, NASA's Environmentally Responsible Aviation Project will assess how well five different coatings prevent insect remains from sticking to the leading edge of the 757's right wing. Bug residue is a nuisance on cars, but on some airplane designs it is also a drag, literally. Studies have shown that keeping the flow smooth, or laminar, over a wing can reduce fuel consumption as much as six percent. Even something as small as a bug on a leading edge can cause turbulent wedges that interrupt laminar flow, resulting in an increase in drag and fuel use.
Engineers at NASA's Langley Research Center in Hampton, VA, developed and tested several non-stick coatings in a small wind tunnel and on the wing of a NASA Langley jet. They selected the best candidates to test on the ecoDemonstrator 757, while a NASA, Boeing, U.S. Department of Transportation (Volpe), and University of California-Davis team looked for an area with a large bug population in which to flight test the surfaces. After narrowing the list of 90 airports to six, Shreveport was chosen based on runway length, temperature, humidity, weather, the ability to handle a 757 aircraft and thunderstorm frequency.
The NASA Langley researchers will work with Boeing pilots and engineers to test the coatings on two of the leading edge slats on the airplane's right wing during the Louisiana flights. The team will establish a bug baseline by using uncoated surfaces to capture insect accumulation rates. Then they will fly untreated control surfaces along with engineered surface samples of the five coatings being tested.
NASA's goals are not only to determine which coating is most effective in decreasing the amount of bug residue, but also to provide data that will allow engineers to measure how reducing the size and specific locations of bug strikes affect laminar flow and help improve fuel efficiency.
According to Boeing, the ecoDemonstrator Program plays a key role in the company's environmental strategy by testing and accelerating new technologies that can reduce fuel use, carbon emissions and noise. In collaboration with NASA and TUI Group, Europe's leading travel group, the ecoDemonstrator 757 began flight tests in March 2015 with a focus on improving aerodynamic efficiency. In 2014, the company tested more than 25 technologies on the ecoDemonstrator 787. In 2012, Boeing tested 15 ecoDemonstrator technologies on an American Airlines 737-800.
With the exception of Boeing proprietary technology, NASA knowledge gained through the ecoDemonstrator research will be publicly available to benefit industry.