The Federal Communications Commission (FCC) will abandon a plan to allow cell phone use on airplanes, chairman Kevin J. Martin said this week. The reason, Martin said, is because it is not clear if the ground networks can handle the calls from 30,000 feet. Both the FCC and FAA must approve the plan before phones can be legally used on board. The FAA had been laying the groundwork to allow cell phones on planes. The FCC has received thousands of letters from air passengers urging the rejection of the proposal, citing the potential for irritating passengers. Martin told reporters the current system is designed for phones to communication with a single cell tower at time. However, aboard a plane, the cell phone can contact many towers at once, tying up circuits. There is a safety issue involved as well, experts say. Safety advocates argue cell phones could interfere with the frequencies used for the plane’s navigational equipment.