New electronic display units are to be fitted in the cockpits of Boeing 737 and 777 airliners to address fears that Wi-Fi signals might cause them to go blank in flight.

In an airworthiness directive published Wednesday, the Federal Aviation Administration (FAA) said the switchover involves 1,149 late-model 737s and 177 777s in the United States alone.

Each installation is estimated to cost about $10,000, said the agency, which set a five-year deadline for the work to be completed.

"We are issuing this (directive) to prevent loss of flight-critical information displayed to the flight crew during a critical phase of flight, such as an approach or takeoff," it said.

Such an incident "could result in loss of airplane control at an altitude insufficient for recovery, or controlled flight into terrain," it added.

Display units are computer screens that give pilots vital in-flight information, such as altitude, airspeed, compass heading and the aircraft's attitude relative to the horizon.

The airworthiness directive -- aviation's version of an automotive recall -- was prompted by fears that Wi-Fi signals might interfere with a display unit, making it go blank.

Satellite Wi-Fi is being added to a growing number of commercial airliners, enabling passengers to log on to the Internet from 35,000 feet (10,000 meters).

In a statement, Honeywell International, which manufactures the display units, said that none of the devices have ever failed in flight due to Wi-Fi interference.

"The only know occurrence was during a developmental test conducted on the ground," it said, adding that, working with Boeing, it has already come up with new display hardware.