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49 U.S. Code § 41725 - Prohibition on certain cell phone voice communications

(a) Prohibition.—The Secretary of Transportation shall issue regulations—
to prohibit an individual on an aircraft from engaging in voice communications using a mobile communications device during a flight of that aircraft in scheduled passenger interstate or intrastate air transportation; and
(2) that exempt from the prohibition described in paragraph (1) any—
member of the flight crew on duty on an aircraft;
flight attendant on duty on an aircraft; and
Federal law enforcement officer acting in an official capacity.
(b) Definitions.—In this section, the following definitions apply:
(1) Flight.—
The term “flight” means, with respect to an aircraft, the period beginning when the aircraft takes off and ending when the aircraft lands.
(2) Mobile communications device.—
(A) In general.—
The term “mobile communications device” means any portable wireless telecommunications equipment utilized for the transmission or reception of voice data.
(B) Limitation.—
The term “mobile communications device” does not include a phone installed on an aircraft.