(c) 2013, Bloomberg News.

(c) 2013, Bloomberg News.

WASHINGTON Airline passengers will be allowed to use smartphones and devices such as Amazon.com's Kindle throughout U.S. flights as soon as the end of this year, with some restrictions, the chief U.S. aviation regulator said.

The Federal Aviation Administration will initially allow gadgets set to so-called airplane mode to be used throughout flights, though heavier devices will have to be stowed during takeoff and landing, agency chief Michael Huerta said Thursday.

The FAA is yielding to pleas from device makers and users who want to stay connected throughout flights, while building in requirements that airlines test for potential electronic interference with planes' controls, develop new safety announcements and consider the implications of devices becoming projectiles during crash landings.

"This is a big win for customers and, frankly, it's about time," Drew Herdener, an Amazon.com spokesman, said in an emailed statement.

Allowing broader use of on-board electronics would help Amazon.com, as Kindle owners may have more time to buy and download content; Gogo, which says it has 82 percent of the inflight Wi-Fi service market in North America; and Qualcomm, which won preliminary regulatory clearance in May for an air-to-ground broadband service.

The FAA now prohibits use of personal electronic devices while a plane is below 10,000 feet, with the exception of portable recorders, hearing aids, heart pacemakers and electric shavers. The restrictions are intended to prevent interference with flight controls, radios and navigation equipment.

Mobile-phone calls and text messages will remain forbidden at any time during flight. They are separately banned over concerns that the signals may interfere with ground networks.

"I did feel that, like any regulation that has been around for a long time, the world has changed a lot in the last 50 years, so let's take a look," Huerta said at a press conference in Washington. "And that's what we did."

Devices allowed on one fleet of aircraft may be prohibited on another under the new policy, and that may mean the speed of implementing the changes will vary, Huerta said.

The bar for getting permission to expand electronics use will be higher if an airline wants its passengers to be able to surf the Internet while pilots land in zero visibility, which requires them to follow radio beams instead of seeing the runway.

Some instrument landing systems may never be qualified for operations while passengers read e-books or load Web pages, Huerta said.

The FAA is creating a team in Washington that will advise inspectors at individual carriers to help speed the process, Huerta said in an interview after the press conference.

"What we're really striving for is consistency," he said. "We're committed to moving very expeditiously."

The recommendations announced Thursday were based on a report by an FAA advisory panel that made its recommendations to the agency in September.

"We've been fighting for our customers on this issue for years testing an airplane packed full of Kindles, working with the FAA, and serving as the device manufacturer on this committee," Amazon's Herdener said.

Delta Air Lines and JetBlue Airways said in statements that they've started the process of winning FAA approvals for broader device usage.

United Continental Holdings Inc.'s United Airlines is "excited to offer this new benefit because our customers tell us they want to use their portable electronic devices," Luke Punzenberger, a spokesman, said in an email.

Brandy King, a Southwest Airlines spokesman, said the carrier will "work diligently and quickly" to allow more use while vetting new procedures through an internal safety review board.

Brett Snyder, who writes the blog Cranky Flier and does consulting work for airports and airlines, said the rules "will create a bit of policing problem" for flight crews because they differentiate between device usage in airplane mode and on Wi-Fi signals.

"For me, I think one of the concerns is that people are going to pay less attention on the ground to safety demonstrations not that a ton of people pay attention anyway but it's just going to cause more distraction," he said.

It will be important for passengers to stop using devices and pay attention during the safety briefing before each flight, Huerta said.

The president of the union representing flight attendants at AMR Corp.'s American Airlines said she welcomed the changes because her members are "frankly tired of feeling like hall monitors when it comes to this issue."

"Once the new policy is safely implemented and we're going to work closely with the carrier to do that it will be a win-win," Laura Glading, president of the Association of Professional Flight Attendants, said in a statement.

The changes will require crew training, Veda Shook, international president of the Association of Flight Attendants, the largest U.S. flight-attendant union, said in an e-mailed statement.

Attendants will work to contain safety risks from loose items and "to find creative, science-based approaches" so passengers comply with new policies and pay attention to safety briefings, Shook said.

Lawmakers, including Senator Claire McCaskill, a Missouri Democrat, have said the FAA was moving too slowly to expand usage and threatened to force changes through legislation.

"This is great news for the traveling public and, frankly, a win for common sense," McCaskill said in an e-mailed statement Thursday.

Huerta said he had to navigate sometimes intense feelings on the issue.

"There are a lot of strongly held opinions as to whether or not this is interference," he said in the interview. "What we wanted to do was take a thoughtful, science-based approach which really addressed the question is there a safety hazard. I think we were able to do that."

_ With assistance from Caroline Chen in New York, Ian King in San Francisco, Jeff Plungis in Washington and Mary Schlangenstein in Dallas.