Sept 30 (Reuters) - The U.S. Federal Aviation Administration is requiring airlines to replace cockpit displays on more than 1,300 Boeing Co airplanes to avoid interference from Wi-Fi and cellular devices.

Airlines will need to replace certain cockpit display units made by Honeywell International Inc used on Boeing's 737 and 777 jets within five years, according to an FAA document. (http://bit.ly/1qTpOYb)

The FAA said the display units were susceptible to interference from Wi-Fi frequencies. Independent tests conducted by the agency and Boeing both showed blanking on the screens when Wi-Fi devices were used near them.

The displays are also susceptible to transmissions from mobile phones, weather radar, and mobile satellite communications, the FAA said.

The display units provide crucial flight information including airspeed, altitude, and navigation information and cost thousands of dollars each. Replacing all the units is expected to cost airlines nearly $14 million, according to the FAA document.

A number of airlines and Honeywell asked the FAA to delay or reduce the effects of the directive, but the regulator said the move was necessary to avoid loss of information during take-offs or landings, which could result in "loss of airplane control at an altitude insufficient for recovery."

Honeywell and Boeing were not immediately available for comment.

(Reporting by Ramkumar Iyer in Bangalore; Editing by Lisa Shumaker)