14 CFR 121.343 -- Flight data recorders.

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eCFR :: 14 CFR 121.343 -- Flight data recorders. (FAR 121.343)

§ 121.343 Flight data recorders.
(a)  Except as provided in paragraphs (b), (c), (d), (e), and (f) of this section, no person may operate a large
airplane that is certificated for operations above 25,000 feet altitude or is turbine-engine powered unless
it is equipped with one or more approved flight recorders that record data from which the following may
be determined within the ranges, accuracies, and recording intervals specified in appendix B of this part:
(1)  Time;
(2)  Altitude;
(3)  Airspeed;
(4)  Vertical acceleration;
(5)  Heading; and
(6)  Time of each radio transmission either to or from air traffic control.
(b)  No person may operate a large airplane type certificated up to and including September 30, 1969, for
operations above 25,000 feet altitude, or a turbine-engine powered airplane certificated before the same
date, unless it is equipped before May 26, 1989 with one or more approved flight recorders that utilize a
digital method of recording and storing data and a method of readily retrieving that data from the storage
medium. The following information must be able to be determined within the ranges, accuracies, and
recording intervals specified in appendix B of this part:
(1)  Time;
(2)  Altitude;
(3)  Airspeed;
(4)  Vertical acceleration;
(5)  Heading; and
(6)  Time of each radio transmission either to or from air traffic control.
(c)  Except as provided in paragraph (l) of this section, no person may operate an airplane specified
in paragraph (b) of this section unless it is equipped, before May 26, 1995, with one or more approved
flight recorders that utilize a digital method of recording and storing data and a method of readily
retrieving that data from the storage medium. The following information must be able to be determined
within the ranges, accuracies and recording intervals specified in appendix B of this part:
(1)  Time;
(2)  Altitude;
(3)  Airspeed;
(4)  Vertical acceleration;
(5)  Heading;
(6)  Time of each radio transmission either to or from air traffic control;
(7)  Pitch attitude;
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eCFR :: 14 CFR 121.343 -- Flight data recorders. (FAR 121.343)

(8)  Roll attitude;
(9)  Longitudinal acceleration;
(10)  Control column or pitch control surface position; and
(11)  Thrust of each engine.
(d)  No person may operate an airplane specified in paragraph (b) of this section that is manufactured after
May 26, 1989, as well as airplanes specified in paragraph (a) of this section that have been type
certificated after September 30, 1969, unless it is equipped with one or more approved flight recorders
that utlitize a digital method of recording and storing data and a method of readily retrieving that data
from the storage medium. The following information must be able to be determined within the ranges,
accuracies, and recording intervals specified in appendix B of this part:
(1)  Time;
(2)  Altitude;
(3)  Airspeed;
(4)  Vertical acceleration;
(5)  Heading;
(6)  Time of each radio transmission either to or from air traffic control;
(7)  Pitch attitude;
(8)  Roll attitude;
(9)  Longitudinal acceleration;
(10)  Pitch trim position;
(11)  Control column or pitch control surface position;
(12)  Control wheel or lateral control surface position;
(13)  Rudder pedal or yaw control surface position;
(14)  Thrust of each engine;
(15)  Position of each thrust reverser;
(16)  Trailing edge flap or cockpit flap control position; and
(17)  Leading edge flap or cockpit flap control position.
For the purpose of this section, manufactured means the point in time at which the airplane inspection
acceptance records reflect that the airplane is complete and meets the FAA-approved type design data.
(e)  After October 11, 1991, no person may operate a large airplane equipped with a digital data bus and
ARINC 717 digital flight data acquisition unit (DFDAU) or equivalent unless it is equipped with one or
more approved flight recorders that utilize a digital method of recording and storing data and a method of
readily retrieving that data from the storage medium. Any parameters specified in appendix B of this
part that are available on the digital data bus must be recorded within the ranges, accuracies,
resolutions, and sampling intervals specified.

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eCFR :: 14 CFR 121.343 -- Flight data recorders. (FAR 121.343)

(f)  After October 11, 1991, no person may operate an airplane specified in paragraph (b) of this section that
is manufactured after October 11, 1991, nor an airplane specified in paragraph (a) of this section that has
been type certificated after September 30, 1969, and manufactured after October 11, 1991, unless it is
equipped with one or more flight recorders that utilize a digital method of recording and storing data and
a method of readily retrieving that data from the storage medium. The parameters specified in appendix
B of this part must be recorded within the ranges, accuracies, resolutions, and sampling intervals
specified.
(g)  Whenever a flight recorder required by this section is installed, it must be operated continuously from the
instant the airplane begins the takeoff roll until it has completed the landing roll at an airport.
(h)  Except as provided in paragraph (i) of this section, and except for recorded data erased as authorized in
this paragraph, each certificate holder shall keep the recorded data prescribed in paragraph (a), (b), (c),
or (d) of this section, as appropriate, until the airplane has been operated for at least 25 hours of the
operating time specified in § 121.359(a). A total of 1 hour of recorded data may be erased for the purpose
of testing the flight recorder or the flight recorder system. Any erasure made in accordance with this
paragraph must be of the oldest recorded data accumulated at the time of testing. Except as provided
in paragraph (i) of this section, no record need be kept more than 60 days.
(i)  In the event of an accident or occurrence that requires immediate notification of the National
Transportation Safety Board under part 830 of its regulations and that results in termination of the flight,
the certificate holder shall remove the recording media from the airplane and keep the recorded data
required by paragraph (a), (b), (c), or (d) of this section, as appropriate, for at least 60 days or for a
longer period upon the request of the Board or the Administrator.
(j)  Each flight recorder required by this section must be installed in accordance with the requirements of §
25.1459 of this chapter in effect on August 31, 1977. The correlation required by § 25.1459(c) of this
chapter need be established only on one airplane of any group of airplanes—
(1)  That are of the same type;
(2)  On which the model flight recorder and its installation are the same; and
(3)  On which there is no difference in the type design with respect to the installation of those first pilot's
instruments associated with the flight recorder. The most recent instrument calibration, including the
recording medium from which this calibration is derived, and the recorder correlation must be
retained by the certificate holder.
(k)  Each flight recorder required by this section that records the data specified in paragraph (a), (b), (c),
or (d) of this section, as appropriate, must have an approved device to assist in locating that recorder
under water.
(l)  No person may operate an airplane specified in paragraph (b) of this section that meets the Stage 2
noise levels of part 36 of this chapter and is subject to § 91.801(c) of this chapter unless it is equipped
with one or more approved flight data recorders that utilize a digital method of recording and storing data
and a method of readily retrieving that data from the storage medium. The information specified
in paragraphs (c)(1) through (c)(11) of this section must be able to be determined within the ranges,
accuracies and recording intervals specified in appendix B of this part. In addition—
(1)  This flight data recorder must be installed at the next heavy maintenance check after May 26, 1994,
but no later than May 26, 1995. A heavy maintenance check is considered to be any time an aircraft
is scheduled to be out of service for 4 or more days.

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eCFR :: 14 CFR 121.343 -- Flight data recorders. (FAR 121.343)

(2)  By June 23, 1994, each carrier must submit to the FAA Flight Standards Service, Air Transportation
Division (AFS–200), documentation listing those airplanes covered under this paragraph and
evidence that it has ordered a sufficient number of flight data recorders to meet the May 26, 1995,
compliance date for all aircraft on that list.
(3)  After May 26, 1994, any aircraft that is modified to meet Stage 3 noise levels must have the flight
data recorder described in paragraph (c) of this section installed before operating under this part.
(m)  After August 20, 2001, this section applies only to the airplane models listed in § 121.344(l)(2). All other
airplanes must comply with the requirements of § 121.344, as applicable.
[Doc. No. 24418, 52 FR 9636, Mar. 25, 1987, as amended by Amdt. 121–197, 53 FR 26147, July 11, 1988; Amdt.
121–238, 59 FR 26900, May 24, 1994; Amdt. 121–338, 73 FR 12565, Mar. 7, 2008]

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