scope:

PURPOSE AND SCOPE

This document contains the Minimum Operational Performance Standard for On Board Weight and Balance Systems for Large Aeroplanes (CS-25). These standards specify the minimum performance expected from such an On Board Weight and Balance System.

Compliance with this standard is recommended as one means of assuring that the equipment will perform its intended function(s) satisfactory under all conditions normally encountered in routine aeronautical operation.

This minimum operational performance standard is designed to ensure that equipment compliant to it will get the necessary regulatory approval (this is generally facilitated by the recognition of such standards by the relevant authorities as an acceptable means of compliance with the applicable regulations).

Applicable regulations and certification specifications are (for other relevant standards refer also to Chapter 1.6):

- EASA CS-25,

- EC Regulation 965/2012 CAT.POL.MAB.100 Mass and balance, loading, and

- EC Regulation 965/2012 CAT.POL.MAB.105 Mass and balance data and documentation

The document is structured as follows:

Chapter 1 of this document provides information required to understand the need for the equipment characteristics and tests defined in the remaining chapters. It describes typical equipment applications and operational objectives and is the basis for the performance criteria stated in Chapter 2 to Chapter 4. Definitions essential to proper understanding of this document are also provided in Chapter 1.

Chapter 2 contains general design requirements.

Chapter 3 contains the minimum performance specification for the equipment, defining performance under standard conditions.

Chapter 4 contains the minimum performance specification for the equipment, defining performance under operational conditions..

Chapter 5 describes recommended test procedures for demonstrating compliance with Chapters 3 and 4.

Operational performance standards for functions or components that refer to equipment capabilities that exceed the stated minimum requirements are identified as optional features. If applicable, performance requirements and associated test procedures are developed for these optional features as well.

The word "equipment" as used in this document includes all components and units necessary for the system to properly perform its intended function(s). For example, the "equipment" may include sensors, displays, wire harnesses, software. In the case of this example, all of the foregoing components and units comprise the "equipment." It should not be inferred from this example that each design will necessarily include all of the foregoing components or units. This will depend on the specific design chosen by the manufacturer.

This MOPS applies to a specific defined function. The equipment may have additional features related to that function for which there are no specified minimum performance requirements. For example, many VHF radios have an active-standby frequency "flipflop" feature for which there are no specified requirements or tests. Equipment may also have additional functions for which other MOPS or ETSOs may be applicable or, it may contain additional functions not defined by any MOPS or ETSO and, non ETSO function guidance may be applicable.