ARP-4754A

ARP-4754A ==> Guidelines for Development of Civil Aircraft and Systems (2010)

https://www.scribd.com/document/427190768/Sae-Arp4754-Rev-A

https://taoscertification.com/wp-content/uploads/2017/05/What-is-ARP-4754A-really.pdf

https://hmediastorageansi.blob.core.chinacloudapi.cn/t-1-resource/3dffce51-8341-b9ba-2d28-e8d3fac3ea7c.pdf

https://taoscertification.com/wp-content/uploads/2017/05/Webinar_SAE-ARP-4761-and-4754A.pdf

• ARP 4754A a standard for safety-oriented system engineering practice. Its primary focus is safety and airworthiness certification. ARP 4754A is a guideline for aircraft/systems development processes considering the overall aircraft operating environment and it is tightly connected with the system safety assessment process. It includes validation of requirements and verification of the design implementation for certification and process assurance. ARP-4754A is in the path of showing compliance to the Aviation regulations. 

Once the Development Assurance Levels (DALs) for each aircraft function (criticality of function based on its severity classification like Catastrophic, Hazardous, Major, Minor, No Safety Effects) are identified by ARP 4761 safety assessment techniques (as DAL A, B, C, D or E), one uses ARP 4754A as guidance to develop those functions, related systems and items based on their DALs. High criticality functions get more development assurance rigor to mitigate errors. Thus, ARP 4754A also provides cost effective safety management strategy. ARP 4754A fills the gaps by integrating safety processes into aircraft and system development processes and meeting regulatory requirements for certification. Although It focuses on safety implications between the life-cycle processes, its weakness is it doesn’t provide enough detailed information for each development elements like configuration management, certification, requirement management, etc. 

Overall system engineering processes, life-cycle management, baseline management, quality management, configuration management, project management activities, etc. are defined in industry best practices and guidelines (Eg. ISO, IEEE, EIA, CMMI, SAE, RTCA, etc.). ISO/IEC/IEEE 15288 System Life Cycle processes 

for best results, ARP 4754A should be used in conjunction with other common industry guidelines (System engineering standards, CMMI, configuration management standards, quality management system standards, SMS, etc.) and companies should integrate safety processes into their internal process infrastructure. We should keep this in mind that every guideline has its own purpose, and we need to understand the intent first and customize the scope according to the product’s need or mandated by customers and aviation authorities. 

ARP-4754A Contents (Guidelines for Development of Civil Aircraft and Systems)

1. Scope

     1.1 Purpose

     1.2 Document Background

2. References

     2.1 Applicable Documents

             2.1.1 SAE Publications

             2.1.2 FAA Publications

             2.1.3 EASA Publications

             2.1.4 RTCA Publications

             2.1.5 EUROCAE Publications

      2.2 Definitions

      2.3 Abbreviations and Acronyms

3. Development Planning

     3.1 Planning Process

     3.2 Transition Criteria

             3.2.1 Deviations from Plans

4. Aircraft and Subsystem Development Process

     4.1 Conceptual Aircraft/System Development Process

             4.1.1 Development Assurance

             4.1.2 Introduction to Development Assurance Process

             4.1.3 Introduction to Hierarchical Safety Requirements Generated from Safety Analysis

             4.1.4 Identification of Aircraft-Level Functions, Function Requirements and Function Interfaces

             4.1.5 Allocation of Aircraft Functions to Systems

             4.1.6 Development of System Architecture

             4.1.7 Allocation of System Requirements to Items

             4.1.8 System Implementation

     4.2 Aircraft Function Development

     4.3 Allocation of Aircraft Functions to Systems

     4.4 Development of System Architecture

     4.5 Allocation of System Requirements to Items

     4.6 System Implementation

             4.6.1 Information Flow - System Process To & From Item Process(es)

                        4.6.1.1 Information Flow From System Process To Hardware/Software Processes

                        4.6.1.2 Information Flow From Hardware/Software Processes To System Process

                        4.6.1.3 Information Flow between Hardware Design Life Cycle and Software Life Cycle Processes

            4.6.2 Hardware and Software Design/Build

            4.6.3 Electronic Hardware/Software Integration

            4.6.4 Aircraft/System Integration

5. Integral Processes

5.1 Safety Assessment

5.1.1 Functional Hazard Assessments

5.1.2 Preliminary Aircraft / System Safety Assessment

5.1.3 Aircraft / System Safety Assessment

5.1.4 Common Cause Analysis

5.1.5 Safety Program Plan

5.1.6 Safety-Related Flight Operations or Maintenance Tasks

5.1.7 Relationship with In-Service Safety

5.2 Development Assurance Level Assignment

5.2.1 General Principles - Introduction to Development Level Assignment

5.2.2 FDAL and IDAL

5.2.3 Detailed FDAL and IDAL Assignment Guidelines

          5.2.3.1 FDAL Assignment without System Architecture Consideration

          5.2.3.2 FDAL Assignment with System Architecture Consideration

                      5.2.3.2.1 Independence Attributes

                                     5.2.3.2.1.1 Functional Independence

                                     5.2.3.2.1.2 Item Development Independence

                                     5.2.3.2.1.3 Summary of Functional and Item Development Independence

                       5.2.3.2.2 FDAL and IDAL Assignment Process

                       5.2.3.2.3 FDAL and IDAL Assignment cases

                                      5.2.3.2.3.1 Case 1: Neither Functional nor Item Development Independence

                                      5.2.3.2.3.2 Case 2: Functional Independence and Item Development Independence

                                      5.2.3.2.3.3 Case 3: Functional Independence is claimed but not Item Development Independence

                                      5.2.3.2.3.4 Case 4: No functional independence but Item development independence

         5.2.3.3 IDAL Assignment Additional Considerations

5.2.4 FDAL Assignment Taking Credit for External Events

5.3 Requirements Capture

5.3.1 Types of Requirements

           5.3.1.1 Safety Requirements

           5.3.1.2 Functional Requirements

                          5.3.1.2.1 Customer Requirements

                          5.3.1.2.2 Operational Requirements

                          5.3.1.2.3 Performance Requirements

                          5.3.1.2.4 Physical and Installation Requirements

                          5.3.1.2.5 Maintainability Requirements

                          5.3.1.2.6 Interface Requirements

           5.3.1.3 Additional Certification Requirements

           5.3.1.4 Derived Requirements

           5.3.1.5 Re-use of Existing Certificated Systems and Items

5.3.2 Deriving Safety-related Requirements from the Safety Analysis

5.3.3 Capturing Maintenance Requirements for In-service Use

5.4 Requirements Validation

5.4.1 Process Objectives

5.4.2 Validation Process Model

5.4.3 Correctness Checks

5.4.4 Completeness Checks

           5.4.4.1 Templates and Checklists

           5.4.4.2 User, Operator and Maintainer Involvement

5.4.5 Validation Rigor

5.4.6 Validation Methods

            5.4.6.1 Recommended Methods

5.4.7 Validation Data

            5.4.7.1 Validation Plan

            5.4.7.2 Validation Tracking

            5.4.7.3 Validation Summary

5.5 Implementation Verification

5.5.1 Verification Process Objectives

5.5.2 Verification Process Model

5.5.3 Verification Rigor

5.5.4 Verification Planning

5.5.5 Verification Methods

            5.5.5.1 Inspection or Review

            5.5.5.2 Analysis

            5.5.5.3 Modeling

                           5.5.5.3.1 Coverage Analysis

            5.5.5.4 Testing or Demonstration

                           5.5.5.4.1 Test Facilities

            5.5.5.5 Similarity / Service Experience

            5.5.5.6 Recommended Verification Methods

5.5.6 Verification Data

            5.5.6.1 Verification Plan

            5.5.6.2 Verification Procedures and Results

            5.5.6.3 Verification Matrix

            5.5.6.4 Verification Summary

5.6 Configuration Management

5.6.1 Configuration Management Process Objectives

5.6.2 Configuration Management Process Activities

           5.6.2.1 Configuration Management Plan

           5.6.2.2 Configuration Identification

           5.6.2.3 Configuration Baseline Establishment

           5.6.2.4 Change Control and Problem Reporting

           5.6.2.5 Archive and Retrieval

           5.6.2.6 Data Control Categories

5.7 Process Assurance

5.7.1 Process Objectives

5.7.2 Process Assurance Plan

5.7.3 Project Plan Reviews

5.7.4 Evidence of Process Assurance

5.8 Certification and Regulatory Authority Coordination

5.8.1 Certification Planning

5.8.2 Agreement on the Proposed Means of Compliance

5.8.3 Compliance Substantiation

5.8.4 Certification Data

           5.8.4.1 Certification Plan

           5.8.4.2 Configuration Index

           5.8.4.3 Development Plan

           5.8.4.4 Design Description

6. Modification to Aircraft or Systems

6.1 Modification Process Overview

6.2 Modification Management Process

6.3 Modification Impact Analysis

6.4 Modification Categorization and Administration

6.5 Evidence for Acceptability of a Modification

        6.5.1 Use of Service History

6.6 Considerations for Modifications

        6.6.1 Introducing a New Aircraft-Level Function

        6.6.2 Replacing Item or System with Another on an Existing Aircraft

        6.6.3 Adapting Existing Item or System to a Different Aircraft Type

        6.6.4 Modification to Item or System Without Adding a Function

        6.6.5 STC Production Introduction

Appendix A: Process Objectives Data

Appendix B: Safety Program Plan

Appendix C: FDAL/IDAL Assignment Process Example

Appendix A: Process Objectives Data

Table A-1 process objectives, outputs and system control category (Total 34 objectives for 8 processes)

1.0 Planning Process

1.1 System development and integral processes activities are defined.

1.2 Transition criteria and inter-relationship among processes are defined.

2.0 Aircraft and System Development Processes and Requirements Capture

2.1 Aircraft-level functions, functional requirements, functional interfaces and assumptions are defined.

2.2 Aircraft functions are allocated to systems.

2.3 System requirements, including assumptions and system interfaces are defined.

2.4 System derived requirements (including derived safety-related requirements) are defined and rationale explained.

2.5 System architecture is defined.

2.6 System requirements are allocated to the items.

2.7 Appropriate item, system and aircraft integrations are performed.

3.0 Safety Assessment Process

3.1 The aircraft/system functional hazard assessment is performed.

3.2 The preliminary aircraft safety assessment is performed.

3.3 The preliminary system safety assessment is performed.

3.4 The common cause analysis are performed.

3.5 The aircraft safety assessment is performed.

3.6 The system safety assessment is performed.

3.7 Independence requirements in functions, systems and items are captured.

4.0 Requirements Validation Process

4.1 Aircraft, system and item requirements are complete and correct

4.2 Assumptions are justified and validated

4.3 Derived requirements are justified and validated

4.4 Requirements are traceable.

4.5 Validation compliance substantiation is provided

5.0 Implementation Verification Process

5.1 Test or demonstration procedures are correct.

5.2 Verification demonstrates intended function and confidence of no unintended function impacts to safety.

5.3 Product implementation complies with aircraft, and system requirements.

5.4 Safety requirements are verified.

5.5 Verification compliance substantiation is included.

5.6 Assessment of deficiencies and their related impact on safety is identified.

6.0 Configuration Management Process

6.1 Configuration items are identified.

6.2 Configuration baseline and derivatives are established.

6.3 Problem reporting, change control, change review, and configuration status accounting are established.

6.4 Archive and retrieval are established.

7.0 Process Assurance Process

7.1 Assurance is obtained that necessary plans are developed and maintained for all aspects of system certification.

7.2 Development activities and processes are conducted in accordance with those plans.

8.0 Certification and Regulatory Authority Coordination Process

8.1 Compliance substantiation is provided.