14 CFR § 135.151

No person may operate a multiengine, turbine-powered airplane or rotorcraft having a passenger seating configuration of six or more and for which two pilots are required by certification or operating rules unless it is equipped with an approved cockpit voice recorder that:

Is installed in compliance with § 23.1457(a)(1) and (2), (b), (c), (d)(1)(i), (2) and (3), (e), (f), and (g); § 25.1457(a)(1) and (2), (b), (c), (d)(1)(i), (2) and (3), (e), (f), and (g), § 27.1457(a)(1) and (2), (b), (c), (d)(1)(i), (2) and (3), (e), (f), and (g); or § 29.1457(a)(1) and (2), (b), (c), (d)(1)(i), (2) and (3), (e), (f), and (g) of this chapter, as applicable; and

Is operated continuously from the use of the check list before the flight to completion of the final check list at the end of the flight.

No person may operate a multiengine, turbine-powered airplane or rotorcraft having a passenger seating configuration of 20 or more seats unless it is equipped with an approved cockpit voice recorder that—

Is installed in accordance with the requirements of § 23.1457 (except paragraphs (a)(6), (d)(1)(ii), (4), and (5)); § 25.1457 (except paragraphs (a)(6), (d)(1)(ii), (4), and (5)); § 27.1457 (except paragraphs (a)(6), (d)(1)(ii), (4), and (5)); or § 29.1457 (except paragraphs (a)(6), (d)(1)(ii), (4), and (5)) of this chapter, as applicable; and

Is operated continuously from the use of the check list before the flight to completion of the final check list at the end of the flight.

In the event of an accident, or occurrence requiring immediate notification of the National Transportation Safety Board which results in termination of the flight, the certificate holder shall keep the recorded information for at least 60 days or, if requested by the Administrator or the Board, for a longer period. Information obtained from the record may be used to assist in determining the cause of accidents or occurrences in connection with investigations. The Administrator does not use the record in any civil penalty or certificate action.

For those aircraft equipped to record the uninterrupted audio signals received by a boom or a mask microphone the flight crewmembers are required to use the boom microphone below 18,000 feet mean sea level. No person may operate a large turbine engine powered airplane manufactured after October 11, 1991, or on which a cockpit voice recorder has been installed after October 11, 1991, unless it is equipped to record the uninterrupted audio signal received by a boom or mask microphone in accordance with § 25.1457(c)(5) of this chapter.

In complying with this section, an approved cockpit voice recorder having an erasure feature may be used, so that during the operation of the recorder, information:

Recorded in accordance with paragraph (a) of this section and recorded more than 15 minutes earlier; or

Recorded in accordance with paragraph (b) of this section and recorded more than 30 minutes earlier; may be erased or otherwise obliterated.

By April 7, 2012, all airplanes subject to paragraph (a) or paragraph (b) of this section that are manufactured before April 7, 2010, and that are required to have a flight data recorder installed in accordance with § 135.152, must have a cockpit voice recorder that also—

Meets the requirements in § 23.1457(d)(6) or § 25.1457(d)(6) of this chapter, as applicable; and

If transport category, meet the requirements in § 25.1457(a)(3), (a)(4), and (a)(5) of this chapter.

No person may operate a multiengine, turbine-powered airplane or rotorcraft that is manufactured on or after April 7, 2010, that has a passenger seating configuration of six or more seats, for which two pilots are required by certification or operating rules, and that is required to have a flight data recorder under § 135.152, unless it is equipped with an approved cockpit voice recorder that also—

Is installed in accordance with the requirements of § 23.1457 (except for paragraph (a)(6)); § 25.1457 (except for paragraph (a)(6)); § 27.1457 (except for paragraph (a)(6)); or § 29.1457 (except for paragraph (a)(6)) of this chapter, as applicable; and

Is operated continuously from the use of the check list before the flight, to completion of the final check list at the end of the flight; and

Retains at least—

The last 25 hours of recorded information using a recorder that meets the standards of TSO-C123c, or later revision, if:

Manufactured on or after May 16, 2025, for a transport category aircraft type-certificated with 30 or more passenger seats; or

Manufactured on or after February 2, 2027, for airplanes or rotorcraft with a maximum certified takeoff weight (MCTOW) of 59,525 pounds or more and type-certificated with 29 or fewer passenger seats; or

Manufactured on or after February 2, 2029, for airplanes or rotorcraft with a maximum certified takeoff weight (MCTOW) of 59,524 pounds or less.

The last 2 hours of recorded information using a recorder that meets the standards of TSO-C123a, or later revision, unless the airplane or rotorcraft meets the manufacturing date and requirements found in paragraphs (g)(1)(iii)(A)(1), (g)(1)(iii)(A)(2), or (g)(1)(iii)(A)(3) of this section.

For all airplanes or rotorcraft manufactured on or after December 6, 2010, also meets the requirements of § 23.1457(a)(6); § 25.1457(a)(6); § 27.1457(a)(6); or § 29.457(a)(6) of this chapter, as applicable.

No person may operate a multiengine, turbine-powered airplane or rotorcraft that is manufactured on or after April 7, 2010, has a passenger seating configuration of 20 or more seats, and that is required to have a flight data recorder under § 135.152, unless it is equipped with an approved cockpit voice recorder that also—

Is installed in accordance with the requirements of § 23.1457 (except for paragraph (a)(6)); § 25.1457 (except for paragraph (a)(6)); § 27.1457 (except for paragraph (a)(6)); or § 29.1457 (except for paragraph (a)(6)) of this chapter, as applicable; and

Is operated continuously from the use of the check list before the flight, to completion of the final check list at the end of the flight; and

Retains at least—

The last 25 hours of recorded information using a recorder that meets the standards of TSO-C123c, or later revision, if:

Manufactured on or after May 16, 2025, for airplanes or rotorcraft type-certificated with 30 or more passenger seats; or

Manufactured on or after February 2, 2027, for airplanes or rotorcraft with a maximum certified takeoff weight (MCTOW) of 59,525 pounds or more and type-certificated with 29 or fewer passenger seats; or

Manufactured on or after February 2, 2029, for airplanes or rotorcraft with a maximum certified takeoff weight (MCTOW) of 59,524 pounds or less.

The last 2 hours of recorded information using a recorder that meets the standards of TSO-C123a, or later revision, unless the airplane or rotorcraft meets the manufacturing date and requirements found in paragraphs (g)(2)(iii)(A)(1), (g)(2)(iii)(A)(2), or (g)(2)(iii)(A)(3) of this section.

For all airplanes or rotorcraft manufactured on or after December 6, 2010, also meets the requirements of § 23.1457(a)(6); § 25.1457(a)(6); § 27.1457(a)(6); or § 29.457(a)(6) of this chapter, as applicable.

All airplanes or rotorcraft required by this part to have a cockpit voice recorder and a flight data recorder, that install datalink communication equipment on or after December 6, 2010, must record all datalink messages as required by the certification rule applicable to the aircraft.