“Anytime you have a rule that appears to be about safety but it is widely ignored, it undermines the importance of other rules about safety,” she said. “If people are being told to do things because it keeps the public safe, there needs to be solid scientific data that supports that, and clearly that was not the case with this prohibition.”

Airlines, too, have been eager to relax the rules, which are seen often as a distraction for flight attendants forced to police the cabin. They are also expanding the use of wireless systems on board, offering live television and considering streaming movies to passengers’ own devices.

But given the persistent uncertainty, as well as the potential risk, the F.A.A. has taken a cautious approach. In recent years, pilots have reported hundreds of episodes in which they suspected that electronic devices might have interfered with instruments on the flight deck. But the evidence has been largely anecdotal, and neither regulators nor airlines have been able to formally substantiate them.

The effort to regulate electronics on planes began in the late 1950s, when studies found that passengers carrying portable FM radios interfered with radar navigation systems used at the time.

The panel recommended that the F.A.A. require airlines to demonstrate that their planes were immune to electromagnetic interference. Many have done so already when installing Wi-Fi. Once that is done the agency can allow the airlines to lift the restrictions. That could happen next year.

Consumer electronics makers have long called for the relaxed rules. Amazon, which makes the Kindle electronic reader, once loaded a plane with Kindles to see whether it would have an impact on flight instruments.

“We’ve been fighting for our customers on this issue for years — testing an airplane packed full of Kindles, working with the F.A.A., and serving as the device manufacturer on this committee,” Drew Herdener, a spokesman for Amazon, which makes the Kindle. “This is a big win for customers and, frankly, it’s about time.”