14 CFR 121.344a -- Digital flight data recorders for 10–19 seat airplanes.

10/11/23, 11:33 AM

eCFR :: 14 CFR 121.344a -- Digital flight data recorders for 10–19 seat airplanes. (FAR 121.344a)

§ 121.344a Digital flight data recorders for 10–19 seat airplanes.
(a)  Except as provided in paragraph (f) of this section, no person may operate under this part a turbineengine-powered airplane having a passenger seating configuration, excluding any required crewmember
seat, of 10 to 19 seats, that was brought onto the U.S. register after, or was registered outside the United
States and added to the operator's U.S. operations specifications after, October 11, 1991, unless it is
equipped with one or more approved flight recorders that use a digital method of recording and storing
data and a method of readily retrieving that data from the storage medium. On or before August 20,
2001, airplanes brought onto the U.S. register after October 11, 1991, must comply with either the
requirements in this section or the applicable paragraphs in § 135.152 of this chapter. In addition, by
August 20, 2001.
(1)  The parameters listed in §§ 121.344(a)(1) through 121.344(a)(18) of this part must be recorded with
the ranges, accuracies, and resolutions specified in Appendix B of part 135 of this chapter, except
that—
(i)  Either the parameter listed in § 121.344 (a)(12) or (a)(15) of this part must be recorded; either
the parameters listed in § 121.344(a)(13) or (a)(16) of this part must be recorded; and either
the parameter listed in § 121.344(a)(14) or (a)(17) of this part must be recorded.
(ii)  For airplanes with more than two engines, the parameter described in § 121.344(a)(18) of this
part must also be recorded if sufficient capacity is available on the existing recorder to record
that parameter;
(iii)  Parameters listed in §§ 121.344(a)(12) through 121.344(a)(17) of this part each may be
recorded from a single source;
(iv)  Any parameter for which no value is contained in Appendix B of part 135 of this chapter must
be recorded within the ranges, accuracies, and resolutions specified in Appendix M of this part.
(2)  Commensurate with the capacity of the recording system (FDAU or equivalent and the DFDR), the
parameters listed in §§ 121.344(a)(19) through 121.344(a)(22) of this part also must be recorded
within the ranges, accuracies, resolutions, and recording intervals specified in Appendix B of part
135 of this chapter.
(3)  The approved flight recorder required by this section must be installed as soon as practicable, but
no later than the next heavy maintenance check or equivalent after August 18, 1999. A heavy
maintenance check is considered to be any time an airplane is scheduled to be out of service for 4
more days and is scheduled to include access to major structural components.
(b)  For a turbine-engine-powered airplanes having a passenger seating configuration, excluding any required
crewmember seat, of 10 to 19 seats, that are manufactured after August 18, 2000.
(1)  The parameters listed in §§ 121.344(a)(1) through 121.344(a)(57) of this part, must be recorded
within the ranges, accuracies, resolutions, and recording intervals specified in Appendix M of this
part.
(2)  Commensurate with the capacity of the recording system, all additional parameters listed in §
121.344(a) of this part for which information sources are installed and which are connected to the
recording system, must be recorded within the ranges, accuracies, resolutions, and sampling
intervals specified in Appendix M of this part by August 20, 2001.

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-G/part-121/subpart-K/section-121.344a

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10/11/23, 11:33 AM

eCFR :: 14 CFR 121.344a -- Digital flight data recorders for 10–19 seat airplanes. (FAR 121.344a)

(c)  For all turbine-engine-powered airplanes having a passenger seating configuration, excluding any
required crewmember seats, of 10 to 19 seats, that are manufactured after August 19, 2002, the
parameters listed in § 121.344(a)(1) through (a)(88) of this part must be recorded within the ranges,
accuracies, resolutions, and recording intervals specified in Appendix M of this part.
(d)  Each flight data recorder system required by this section must be installed in accordance with the
requirements of § 23.1459(a) (except paragraphs (a)(3)(ii) and (6)), (b), (d) and (e) of this chapter. A
correlation must be established between the values recorded by the flight data recorder and the
corresponding values being measured. The correlation must contain a sufficient number of correlation
points to accurately establish the conversion from the recorded values to engineering units or discrete
state over the full operating range of the parameter. A single correlation may be established for any group
of airplanes—
(1)  That are of the same type;
(2)  On which the flight recorder system 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 sensors
associated with the flight data recorder system. Correlation documentation must be maintained by
the certificate holder.
(e)  All airplanes subject to this section are also subject to the requirements and exceptions stated in §
121.344(g) through (k) and § 121.346.
(f)  For airplanes that were manufactured before August 18, 1997, the following airplane types need not
comply with this section, but must continue to comply with applicable paragraphs of § 135.152 of this
chapter, as appropriate: Beech Aircraft–99 Series, Beech Aircraft 1300, Beech Aircraft 1900C,
Construcciones Aeronauticas, S.A. (CASA) C–212, deHavilland DHC–6, Dornier 228, HS–748, Embraer
EMB 110, Jetstream 3101, Jetstream 3201, Fairchild Aircraft SA–226, Fairchild Metro SA–227.
(g)  All airplanes subject to the requirements of this section that are manufactured on or after April 7, 2010,
must have a digital flight data recorder installed that also—
(1)  Meets the requirements in § 23.1459(a)(3), (a)(6), and (a)(7) or § 25.1459(a)(3), (a)(7), and (a)(8) of
this chapter, as applicable; and
(2)  Retains the 25 hours of recorded information required in § 121.344(g) using a recorder that meets
the standards of TSO–C124a, or later revision.
[Doc. No. 28109, 62 FR 38380, July 17, 1997; 62 FR 48135, Sept. 12, 1997; 62 FR 65202, Dec. 11, 1997, as
amended by Amdt. 121–300, 68 FR 42936, July 18, 2003; Amdt. 121–338, 73 FR 12566, Mar. 7, 2008; Amdt. 121–
338, 74 FR 32801, July 9, 2009; Amdt. 121–347, 75 FR 7356, Feb. 19, 2010]

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-G/part-121/subpart-K/section-121.344a

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