PURPOSE.

This advisory circular (AC) provides aircraft operators with information and guidance for assistance in the compliance of Federal Aviation Regulations (FAR) Section 91.21. Because of the potential for portable electronic devices to interfere with aircraft communications and navigation equipment, FAR Section 91.21 was established. It prohibits the operation of portable electronic devices aboard U.S.-registered civil aircraft, operated by the holder of an air carrier operating certificate or an operating certificate, or any other aircraft while operating under instrument flight rules. The rule permits use of specified portable electronic devices and other devices that the operator of the aircraft has determined will not cause interference with the safe operation of the aircraft in which it is operated. The recommendations contained herein are one means, but not the only means, of complying with the requirements of FAR Section 91.21, pertaining to the operation of portable electronic