NASA: Significant Fuel Savings In Formation Flight

Trying to imitate birds that conserve energy by “surfing” on the wakes of other birds in V-formation flight, NASA surfed an F/A-18 in the wingtip vortex of a DC-8 late last month, and recorded a 29-percent fuel savings. Unfortunately, finding the sweet spot without computer aid isn’t a simple task. NASA said last week that the airplanes flew at 25,000 feet with a separation of about 200 feet nose-to-tail. Earlier experiments with two F/A-18s showed only an 18-percent fuel savings. While many bird species have figured out that formation flight benefits them, NASA noted that nowhere in nature do you find large and small birds cooperating to achieve this apparently greater efficiency. Related information is available on the NASA Dryden Web site.