{"data":{"id":"us/14-cfr-appendix-e-to-part-91","jurisdiction":"us","citation":"14 CFR Appendix E to Part 91","heading":"Appendix E to Part 91—Airplane Flight Recorder Specifications","body":"Parameters Range Installed system 1 minimum accuracy (to recovered data) Sampling interval (per second) Resolution 4 read out\nRelative Time (From Recorded on Prior to Takeoff) 8 hr minimum ±0.125% per hour 1 1 sec.\nIndicated Airspeed Vso to VD (KIAS) ±5% or ±10 kts., whichever is greater. Resolution 2 kts. below 175 KIAS 1 1% 3\nAltitude −1,000 ft. to max cert. alt. of A/C ±100 to ±700 ft. (see Table 1, TSO C51-a) 1 25 to 150 ft.\nMagnetic Heading 360° ±5° 1 1°\nVertical Acceleration −3g to + 6g ±0.2g in addition to ±0.3g maximum datum 4 (or 1 per second where peaks, ref. to 1g are recorded) 0.03g.\nLongitudinal Acceleration ±1.0g ±1.5% max. range excluding datum error of ±5% 2 0.01g.\nPitch Attitude 100% of usable ±2° 1 0.8°\nRoll Attitude ±60° or 100% of usable range, whichever is greater ±2° 1 0.8°\nStabilizer Trim Position, or Full Range ±3% unless higher uniquely required 1 1% 3\nPitch Control Position 5\nEngine Power, Each Engine: Full Range ±3% unless higher uniquely required 1 1% 3\nFan or N 1 Speed or EPR or Cockpit indications Used for Aircraft Certification OR Maximum Range ±5% 1 1% 3\nProp. speed and Torque (Sample Once/Sec as Close together as Practicable) 1 (prop Speed) 1 (torque) 1%3 1% 3\nAltitude Rate 2 (need depends on altitude resolution) ±8,000 fpm ±10%. Resolution 250 fpm below 12,000 ft. indicated 1 250 fpm. below 12,000\nAngle of Attack 2 (need depends on altitude resolution) −20° to 40° or 100% of usable range ±2° 1 0.8%3\nRadio Transmitter Keying (Discrete) On/Off 1\nTE Flaps (Discrete or Analog) Each discrete position (U, D, T/O, AAP) OR 1\nLE Flaps (Discrete or Analog) Analog 0-100% range ±3% 1 1%3\nEach discrete position (U, D, T/O, AAP) OR 1\nThrust Reverser, Each Engine (Discrete) Analog 0-100% range ±3° 1 1%3\nStowed or full reverse\nSpoiler/Speedbrake (Discrete) Stowed or out 1\nAutopilot Engaged (Discrete) Engaged or Disengaged 1\n1 When data sources are aircraft instruments (except altimeters) of acceptable quality to fly the aircraft the recording system excluding these sensors (but including all other characteristics of the recording system) shall contribute no more than half of the values in this column.\n2 If data from the altitude encoding altimeter (100 ft. resolution) is used, then either one of these parameters should also be recorded. If however, altitude is recorded at a minimum resolution of 25 feet, then these two parameters can be omitted.\n3 Per cent of full range.\n4 This column applies to aircraft manufactured after October 11, 1991.\n5 For Pitch Control Position only, for all aircraft manufactured on or after April 6, 2012, the sampling interval (per second) is 8. Each input must be recorded at this rate. Alternately sampling inputs (interleaving) to meet this sampling interval is prohibited.","path":["Title 14—Aeronautics and Space","CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION","SUBCHAPTER F—AIR TRAFFIC AND GENERAL OPERATING RULES","PART 91—GENERAL OPERATING AND FLIGHT RULES"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-14.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:24:20Z","sha256":"3cabce844c15af27323321fb9be9c8b416c7fa7cf545dba2dfa28d4ffcfaf9ef","source_id":"us-cfr","stale":true,"prev":"us/14-cfr-appendix-d-to-part-91","next":"us/14-cfr-appendix-f-to-part-91"},"notice":"GroundRules: Original legal text. Not legal advice."}