From Sunday, June 22 to Wednesday, July 2, two research aircraft will make a series of low-altitude atmospheric research flights near Philadelphia, Baltimore, and some Virginia cities, including Richmond, as well as over the Los Angeles Basin, Salton Sea, and Central Valley in California. Pilots will operate the aircraft at altitudes lower than typical commercial flights, executing specialized maneuvers such as vertical spirals between 1,000 and 10,000 feet, circling above power plants, landfills, and urban areas. The flights will also include occasional missed approaches at local airports and low-altitude flybys along runways to collect air samples near the surface.…