NASA is investigating ways to reduce the most complained about aspect of aircraft—noise.
Last month, NASA’s Armstrong Flight Research Center in California, US, tested technology to reduce airframe noise, (which it describes as noise produced by non-propulsive parts of the aircraft), during landing. The flights successfully combined several technologies to achieve a greater than 70 per cent reduction in airframe noise.
Technologies included landing gear fairings and cavity treatments and an Adaptive Compliant Trailing Edge (ACTE) wing flap, which had previously been flight-tested to study aerodynamic efficiency.
The experimental landing gear tested by NASA features fairings that are porous along their front, with tiny holes that allow some of the air to flow through the fairing, while also deflecting some of the airflow around the landing gear
The aircraft flew at 350 feet, over an array of 185 microphones on Rogers Dry Lake at Edwards Air Force Base.
NASA principal investigator for Acoustic Research Measurement, Mehdi Khorrami, said, ‘NASA’s goal here was to reduce aircraft noise substantially in order to improve the quality of life for communities near airports. We are very confident that with the tested technologies we can substantially reduce total aircraft noise, and that could really make a lot of flights much quieter.’