NASA says its scientists are studying the effect insects have on aircraft performance, especially during takeoff and landing, in hopes of saying "bug off." Bug splatter that coats aircraft surfaces can disrupt the laminar -- or smooth -- flow of air over an airplane's wings, creating more drag on the airplane and contributing to increased fuel consumption, they said. Researchers at NASA's Langley Research Center in Virginia have run a number of flight tests of airplane coatings that may one day reduce the amount of bug contamination on the wings of commercial aircraft, the agency reported Monday. A series of flights were made to put the coatings through takeoff and landing tests on a NASA aircraft. "The reason we do these tests at low altitudes or do a lot of takeoffs and landings is because bug accumulation occurs at anywhere from the ground to less than 1,000 feet," materials researcher Mia Siochi said. In the tests, the coated surfaces were found to have fewer and smaller bug splats, she said. It will probably be some time before the coatings end up on commercial airliners, the researchers said, because the coatings have to be durable enough to withstand a lot of time in operation, and that will require further testing. In addition, Siochi said, the savings in fuel have to be enough to make up for the cost of applying the coatings. "So we have to get through that hurdle of practical application of these materials," she said.