CS 25.1459 Flight data recorders

• ED Decision 2020/024/R found in: CS-25 Amdt 27 - Large Aeroplanes (Jan 2023)

CS 25.1459 Flight data recorders ED Decision 2020/024/R (See [AMC 25.1459](#_DxCrossRefBm1709821757)) (a) Each flight data recorder required by the operating rules must be approved and must be installed so that – (1) It is supplied with airspeed, altitude, and directional data obtained from sources that meet the accuracy requirements of [CS 25.1323](#_DxCrossRefBm1709821621), [25.1325](#_DxCrossRefBm1709821631) and [25.1327](#_DxCrossRefBm1709821635), as appropriate; (2) The vertical acceleration sensor is rigidly attached, and located longitudinally either within the approved centre of gravity limits of the aeroplane, or at a distance forward or aft of these limits that does not exceed 25% of the aeroplanes mean aerodynamic chord; (3) (i) It receives its electrical power from the bus that provides the maximum reliability for operation of the recorder without jeopardising service to essential or emergency loads; and (ii) It remains powered for as long as possible without jeopardising the emergency operation of the aeroplane; (4) There is an aural or visual means for pre-flight checking of the recorder for proper recording of data in the storage medium; (5) If the recorder has a recording duration of less than 25 hours, there is an automatic means to stop the recording within 10 minutes after crash impact. This requirement does not apply to recorders that are powered solely by the engine-driven electrical generator system; (6) There is a means to record data from which the time of each radio transmission either to or from ATC can be determined; (7) If another recorder is installed to perform the cockpit voice recorder function, any single electrical failure that is external to the recorder dedicated to the flight data recorder function does not disable both the recorders; and (8) If the recorder is deployable, it complies with [CS 25.1457(d)(7)](#_DxCrossRefBm1709821753). (b) If the recorder is not deployable, the container of the recording medium must be located and mounted so as to minimise the probability of the container rupturing, the recording medium being destroyed, or the underwater locating device failing as a result of any possible combinations of: (1) impact with the Earth’s surface; (2) the heat damage caused by a post-impact fire; and (3) immersion in water. If the recorder is deployable, the deployed part must be designed and installed so as to minimise the probability of the recording medium being destroyed or the emergency locator transmitter failing to transmit (after damage or immersion in water) as a result of any possible combinations of: (1) the deployment of the recorder; (2) impact with the Earth’s surface; (3) the heat damage caused by a post-impact fire; and (4) immersion in water. (c) A correlation must be established between the flight data recorder readings of airspeed, altitude, and heading and the corresponding readings (taking into account correction factors) of the first pilot’s instruments. The correlation must cover the airspeed range over which the aeroplane is to be operated, the range of altitude to which the aeroplane is limited, and 360° of heading. Correlation may be established on the ground as appropriate. (d) The container of the flight data recorder must comply with the specifications in CS 25.1457(g) that are applicable to the container of the cockpit voice recorder. (e) Any novel or unique design or operational characteristics of the aeroplane must be evaluated to determine if any dedicated parameters must be recorded on the flight data recorder in addition to, or in place of, the parameters that are required by the existing requirements. [Amdt 25/11] [Amdt 25/18] [Amdt 25/23] [Amdt 25/26]