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CS-E 15 Terminology

Engines (CS-E) · CS-E · EAR revision 7 Dec 2023

IRImplementing rule

CS-E 15 Terminology

(a)The terminology of this CS-E 15 must be used in conjunction with the issue of CS-Definitions current at the date of issue of this CS-E. Where used in CS-E, the terms defined in this paragraph and in CS-Definitions are identified by initial capital letters.

(b)All Engines Extremely Remote means unlikely to occur when considering the total operational life of a number of aircraft of the type in which the Engine is installed, but nevertheless, has to be regarded as being possible. Where numerical values are used this may normally be interpreted as a probability in the range 10-7 to 10-9 per Engine flight hour. Reasonably Probable means unlikely to occur often during the operation of each aircraft of the type but which may occur several times during the total operational life of each aircraft of the types in which the Engine may be installed. Where numerical values are used this may normally be interpreted as a probability in the range 10-3 to 10-5 per Engine flight hour. Remote means unlikely to occur to each aircraft during its total operational life but may occur several times when considering the total operational life of a number of aircraft of the type in which the Engine may be installed. When numerical values are used, this may normally be interpreted as a probability in the range 10-5 to 10-7 per Engine flight hour.

(c)Turbine Engines Hazardous Engine Effect means an effect identified as such under CS-E 510. Major Engine Effect means an effect identified as such under CS-E 510. Minor Engine Effect means an effect identified as such under CS-E 510.

(d)For piston Engines Boost Pressure means the power setting measured relative to standard sea-level atmospheric pressure. Charge Cooling means the percentage degree of charge cooling, quantitatively expressed as: ((t2 – t3) / (t2 – t1)) x 100 where t1 is the temperature of the air entering the charge cooler coolant radiator in the powerplant, t2 is the temperature of the charge without cooling, and t3 is the temperature of the charge with cooling. Critical Attitude means the maximum attitude at which, in standard atmosphere, it is possible to maintain, at a specified rotational speed without ram, a specified power or a specified manifold pressure. Unless otherwise stated, the critical altitude is the maximum altitude at which it is possible to maintain, without ram, at the maximum continuous rotational speed, one of the following: a. The maximum continuous power, in the case of engines for which this power rating is the same at sea level and at the rated altitude. b. The maximum continuous rated manifold pressure, in the case of engines the maximum continuous power of which is governed by a constant manifold pressure. Manifold Pressure means the absolute static pressure measured at the appropriate point in the induction system. Maximum Best Economy Cruising Power Conditions means the crankshaft rotational speed, Engine manifold pressure and any other parameters recommended in the Engine manuals as appropriate for use with economical-cruising mixture strength Maximum Recommended Cruising Power Conditions means the crankshaft rotational speed, Engine manifold pressure and any other parameters recommended in the Engine manuals as appropriate for cruising operation.

(e)Terms associated with Engine Critical Parts Approved Life means the mandatory replacement life of a part which is approved by the Agency. Attributes means inherent characteristics of a finished part that determine its capability. Damage Tolerance means an element of the life management process that recognises the potential existence of component imperfections as the result of inherent material structure, material processing, component design, manufacturing or usage and addresses this situation through the incorporation of fracture resistant design, fracture mechanics, process control, and non-destructive inspection. Engine Critical Part means a part that relies upon meeting prescribed integrity specifications of CS-E 515 to avoid its Primary Failure, which is likely to result in a Hazardous Engine Effect. Engine Flight Cycle means the flight profile, or combination of profiles, upon which the Approved Life is based. Engineering Plan means a compilation of the assumptions, technical data and actions required to establish and to maintain the life capability of an Engine Critical Part. The Engineering Plan is established and executed as part of the pre- and post-certification activities. Manufacturing Plan means a compilation of the part specific manufacturing process constraints, which must be included in the manufacturing definition (drawings, procedures, specifications, etc.) of the Engine Critical Part to ensure that it meets the design intent as defined by the Engineering Plan. Primary Failure means a Failure of a part which is not the result of the prior Failure of another part or system. Service Management Plan means a compilation of the processes for in-service maintenance and repair to ensure that an Engine Critical Part achieves the design intent as defined by the Engineering Plan.

[Amdt. No.: E/1]

[Amdt. No.: E/2]

IR — CS-E · ED Decision 2009/018/R · CS-E Easy Access Rules · EAR revision 7 Dec 2023

All rules in SUBPART A – GENERAL

Consolidated from the EASA Easy Access Rules (revision 7 Dec 2023, extracted 17 Aug 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.

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