Skip to Main Content
FlightPushFLIGHTPUSH
Part 121

Learn

Dashboard My Courses Mastery Map Practice Flight Bag

Resources

CFR & AIM FAA Orders Handbooks & Guides Certification Standards Pilot/Controller Glossary Advisory Circulars Legal Interpretations
Safety Center
Articles Trust Center
Help Center FAQ Status
  1. Reference Library
  2. CFR & AIM
  3. CFR
  4. Part 121
  5. § 121.344a
Loading
flightpush.co home
Loading reference

14 CFR · Part 121

14 CFR § 121.344a

a Digital flight data recorders for 10-19 seat airplanes.

← Previous SectionNext Section →
Read in Subpart K
Part 121 Contents
  • Subpart A: General
  • Subpart E: Approval of Routes: Domestic and Flag Operations
  • Subpart F: Approval of Areas and Routes for Supplemental Operations
  • Subpart G: Manual Requirements
  • Subpart H: Aircraft Requirements
  • Subpart I: Airplane Performance Operating Limitations
  • Subpart J: Special Airworthiness Requirements
  • Subpart K: Instrument and Equipment Requirements
  • Subpart L: Maintenance, Preventive Maintenance, and Alterations
  • Subpart M: Airman and Crewmember Requirements
  • Subpart N: Training Program
  • Subpart O: Crewmember Qualifications
  • Subpart P: Aircraft Dispatcher Qualifications and Duty Time
  • Subpart Q: Flight Time Limitations and Rest Requirements: Domestic Operations
  • Subpart R: Flight Time Limitations: Flag Operations
  • Subpart S: Flight Time Limitations: Supplemental Operations
  • Subpart T: Flight Operations
  • Subpart U: Dispatching and Flight Release Rules
  • Subpart V: Records and Reports
  • Subpart W: Crewmember Certificate: International
  • Subpart X: Emergency Medical Equipment and Training
  • Subpart Y: Advanced Qualification Program
  • Subpart Z: Hazardous Materials Training Program
  • Subpart AA: Continued Airworthiness and Safety Improvements
  • Subpart DD: Special Federal Aviation Regulations
  • Appendix A to Part 121: First Aid Kits and Emergency Medical Kits
  • Appendix B to Part 121: Airplane Flight Recorder Specification
  • Appendix C to Part 121: C-46 Nontransport Category Airplanes
  • Appendix D to Part 121: Criteria for Demonstration of Emergency Evacuation Procedures Under § 121.291
  • Appendix E to Part 121: Flight Training Requirements
  • Appendix F to Part 121: Proficiency Check Requirements
  • Appendix G to Part 121: Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and Equipment Installation; Training Program; Equipment Accuracy and Reliability; Evaluation Program
  • Appendix H to Part 121: Advanced Simulation
  • Appendix K to Part 121: Performance Requirements for Certain Turbopropeller Powered Airplanes
  • Appendix L to Part 121: Type Certification Regulations Made Previously Effective
  • Appendix M to Part 121: Airplane Flight Recorder Specifications
  • Appendix O to Part 121: Hazardous Materials Training Requirements For Certificate Holders
  • Appendix P to Part 121: Requirements for ETOPS and Polar Operations
(a)

Except as provided in paragraph (f) of this section, no person may operate under this part a turbine-engine-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.

(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.

Regulations Referenced

14 CFR 135.15214 CFR 121.34414 CFR Part 135, Appendix B14 CFR Part 121, Appendix M14 CFR 23.145914 CFR 121.34614 CFR 25.1459

Reflects the eCFR edition current as of September 29, 2026. Retrieved from ecfr.gov on October 16, 2026.

Primary Source

  • Official Source (14 CFR · Part 121)