United Airlines and US Airways are the latest airlines to gain approvals from the US Federal Aviation Administration (FAA) to permit passengers to use portable electronic devices (PEDs) from gate to gate.

New guidance adopted by the FAA last week permits passengers to use devices such as tablets, e-readers and smartphones in airplane mode during taxiing, take-off and landing in US airspace.

The new policies will apply to each carrier’s mainline domestic fleets. The airlines follow Delta Air Lines, JetBlue Airways and American Airlines in receiving permission from the FAA to implement the new guidance.

While the new guidance permits passengers to keep their phones on throughout the flight, there will be some limitations to their use. Voice calls will not be permitted due to Federal Communications Commission regulations that prohibit passengers from using their phones’ cellular network to pick up a signal while in the air.

Moreover, using wi-fi below 10,000ft on most US carriers’ aircraft will require some engineering and software changes to work, and how much time and money will be needed to make those changes is still unclear.

Gogo has said that although its air-to-ground system is certified to work on the ground, the technology is engineered to work once the aircraft reaches 10,000ft. That system is on more than 2,000 aircraft flying in North America today, including 90% of US Airways’ domestic aircraft.

Panasonic Avionics, which is providing Ku-band for United on more than 300 aircraft and American on the Boeing 777-300ER, has also said that its system will require a software change to be used gate to gate, which airlines can choose if they want to implement. The system is also certified for use on the ground.

United is also in the process of installing ViaSat’s system on 200 Boeing 737 and 757 aircraft. The connectivity provider has said that its system will not require a change to work below 10,000ft.

Southwest Airlines has not yet submitted a plan to the FAA but says it is working on implementing the new guidance as soon as possible. Global Eagle Entertainment subsidiary Row 44, the airline’s in-flight internet provider, told Flightglobal that its system will not need changes for use throughout the flight.

Row 44 has already carried out substantial testing of the system to ensure the aircraft systems can withstand interference from the devices’ wi-fi signals, but it needs to validate that data with the FAA to ensure it has satisfied all its requirements before Southwest gains the approval, said Global Eagle Entertainment chief technology officer John Guidon last week.

Virgin America, which uses Gogo to provide fleetwide wi-fi, has said it is working on securing the approval this month ahead of the holiday season.

Source: Cirium Dashboard