NTSB Probes Case of Texting Helicopter Pilot Evidence gathered in an investigation of a fatal medical helicopter crash has raised questions about whether the pilot was distracted by personal text messages when he failed to refuel the helicopter before taking off and misjudged how far the aircraft could fly without more fuel. The case, scheduled to be considered at a meeting Tuesday of the National Transportation Safety Board, underscores concerns the board has already expressed that use of cellphones and other distracting electronic devices has increasingly become a factor in accidents and incidents across all modes of transportation - planes, trains, cars, trucks and even ships. The Aug. 26, 2011, accident near Mosby, Mo., which killed four people, appears to be the first fatal commercial aircraft accident investigated by the board in which texting has been implicated. The pilot, James Freudenbert, 34, of Rapid City, S.D., exchanged 20 text messages with an acquaintance over a span of less than two hours before the helicopter crashed into a farm field a little over a mile from where he hoped to refuel, documents made public by NTSB show. At least three of the messages were sent and five received while the helicopter was in flight, although not in the final 11 minutes of the last leg of the flight, according to a timeline prepared by investigators. The timeline indicates Freudenbert also exchanged text messages at the same time he was reporting by radio to a company communications center that the helicopter was low on fuel. The helicopter was on the ground at the time waiting for the patient, who was being transferred from one hospital to another, and a nurse and a paramedic to board. Although the pilot wasn't texting at the time of the crash, it's possible the messaging took his mind off his duties, interrupted his chain of thought and caused him to skip safety steps he might have otherwise performed, experts on human performance and cognitive distractions said. People can't concentrate on two things at once; they can only shift their attention rapidly back and forth, the experts said. But as they do that, the sharpness of their focus begins to erode. "People just have a limited ability to pay attention," said David Strayer, a professor of cognitive and neural science at the University of Utah. It's one of the characteristics of how we are wired. "If we have two things demanding attention, one will take attention away from other," he said. If it happens while sitting behind a desk, it's not that big of a problem. But if you are sitting behind the wheel of a car or in the cockpit of an airplane, you start to get serious compromises in safety. In October 2010, two Northwest Airlines pilots overflew their destination of Minneapolis-St. Paul International Airport by 100 miles while they were engrossed in working on flight schedules on their laptops. A text message - especially one accompanied by an audible alert like a buzz or bell - interrupts a person's thoughts and can be hard to ignore, said Christopher Wickens, a University of Illinois professor emeritus of engineering and aviation psychology. If the subject of the email is especially engaging, or especially emotional, that also makes it hard to ignore, he said. The helicopter was operated by a subsidiary of Air Methods Corp. of Englewood, Colo., the largest provider of air medical emergency transport services in the U.S. The company's policies prohibit the use of electronic devices by pilots during flight.