When certifying a new or modified system, designers conduct a thorough assessment of potential failures to show that there is an inverse relationship between the probability of occurrence and the severity of consequence inherent in its effect AMC The designers also consider whether the design is such that it can lead unnecessarily to errors during manufacture, maintenance or operation or whether the system is vulnerable to foreseeable variations in the operating environment.
The vehicle to report this assessment is commonly known as the System Safety Assessment, and it needs to consider ransom failure of system components as well as systematic errors which might be introduced during the development process. If we slide into one of those rare moments of military honesty, we realize that the technical demands of modern warfare are so complex a considerable percentage of our material is bound to malfunction even before it is deployed against a foe.
We no longer waste manpower by carrying the flag into battle. Instead we need battalions of electronic engineers to keep the terrible machinery grinding. When certifying a new or modified system, designers conduct a thorough assessment of potential failures to demonstrate an inverse relationship exists between the probability of occurrence and the severity of consequence inherent in its effect e.
The collated documents required to demonstrate the above are often collectively referred to as a System Safety Assessment SSA. The SSA is therefore defined as:. Scoping a SSA is a vital but often largely neglected part of the successful start, conduct and completion of the SSA report. There are two fundamentally different approaches:. The contracting agency and the assessor therefore must consider the system level of the design and scope the assessment accordingly.
The illustration in Fig.
For instance:. Think of it as any part that is allocated a configuration identifier. From both a certification and maintenance perspective, items can be further separated into:. Think of it as any self-contained part that performs a distinctive function necessary to the operation of the item. This is the first level at which a SSA is required, and the scope will not include any aircraft interface considerations other than what is flowed down contractually from the Level 4 assessment.
Note that Fig. An example would be the Altitude display system refer Section 4. For a modification e. STC , it is scoped to consider the performance of the new system as well as the interaction between all affected aircraft systems. Safety requirements are functionally decomposed in a hierarchical structure from product i. Altitude Display Unit.
[Free Read] Aircraft System Safety: Assessments for Initial Airworthiness Certification Free
At Level 4 the safety requirements are those requirements generated from the aircraft Functional Hazard Analysis FHA based on required aircraft functions. The Safety Case is a live document, which manages the operational risk once the system enters service. With reference to Fig. Each step will be briefly explored in the sections below:.
Scoping of the assessment is discussed in Section 1. Should the boundaries not be clear to all parties involved in the assessment, it is highly likely some vital part may either be overlooked, fail to integrate appropriately with another part of the assessment, or simply be omitted altogether. Furthermore, boundaries aid with responsibility allocation, especially when integrating products from subcontractors who also have safety deliverables into a higher system.
Within the context of the scope, we next need to plan how we are going to do a systematic assessment, who is going to contribute to each part, and when each part of the Safety Assessment needs to be completed. The output of this phase can then be captured in the first issue of the Safety Plan or Safety Program Plan. See ARPA para 5. It is important to set safety objectives for the system and its functions before any specific architecture or technology is finally decided upon.
Not only is this good Systems Engineering practice i. Unannunciated failures of the TCAS II equipment or its associated transponder, sensors or displays that generate resolution advisories that would cause midair collisions or other catastrophes must be Extremely Improbable. See Chapter 3 for more information on defining the safety target in the FHA. The FHA is the step to determine, in simple terms, what can go wrong at the functional level.
The process begins with the aircraft-level FHA to assess the significant failure conditions attached to given aircraft functions. After functions are assigned to specific aircraft systems, the FHA is then repeated at the system level. The agreed Safety Assessment strategy now needs rigorous implementation to ensure that the aims refer Section 1.
Further guidance and examples on how this implementation can be accomplished are provided in subsequent chapters. The objective it to prove the safety integrity of that level and summarise the key aspects which need to be consider at the next level of integration.
For each level of integration, a clear set of recommendations should be made stating whether the system or equipment should either be accepted into service, allowed to proceed to the next project phase, or describe any further work required to overcome any shortcomings that have been identified prior to continuing to the next project phase.
Any limitations or safety-related restrictions on the use of the system should be stipulated, which at platform level might include:. SAE ARPA is of particular note here, as it provides recommended practices for the development of aircraft systems taking into account the overall aircraft operating environment and functions. This includes:. Table 1. To provide a comprehensive demonstration of the concepts discussed in this book, each chapter in this book will apply the theory discussed to the following case study: let us assume we have a customer who has a requirement to upgrade the avionics on a large military transport aircraft by replacing the old, now unreliable, analogue displays see Section 1.
We will also assume that the customer has agreed to use the safety criteria of CS For the purposes of this case study, we shall assume that the legacy system comprised a number of totally independent Line Replaceable Units LRUs , with the attitude and altitude information being presented on different displays as shown in Fig. The bellows were attached to a needle which moves as the bellows expanded or contracted dependent on atmospheric pressure and therefore altitude.
- The Art of Brave!
- Flames of Gold!
- Vertical Coupling And Decoupling in the Lithosphere (Geological Society Special Publication No. 227).
- Transform Your Beliefs, Transform Your Life: EFT Tapping Using Matrix Reimprinting!
- Growth of algebras and Gelfand-Kirillov dimension;
The IRU used a synchro system to transmit attitude information based on displacement from the horizontal see Fig. A syncho consisted of a static element the Stator and a rotating element within it the rotor. Within the IRU, a field is set up in each of the three legs of the stator.
This is as a result of the relative angle pitch of the Gyro connected to the Rotor RA. This relative angle will cause each leg to have a different field induced within it. These different fields will be replicated in the corresponding stator leg of the stator SB within the ADI.
Aircraft System Safety - Duane Kritzinger - Häftad () | Bokus
For the purposes of this case study, we shall assume that the upgraded avionics utilises the same principles, though looks significantly different as can be seen in Fig. The display system presents the crew with key flight information including attitude and altitude on an integrated display as can be seen in Fig. The display system for each pilot comprises three different key LRUs:. The DCUs include comparators which determine if there is a discrepancy between the No. The case study parameters being compared are:.
The ADC is connected to the pitot-static system, with both the No.
Shop by category
The TAT probe compresses the impacting air to zero speed, and the resulting temperature causes a change in the resistance of the sensing element. The air data then convert this resistance to temperature. The air temperature is used to calibrate the impact pressure as well as in determining air density. Attitude reference data are determined within the IRUs with each utilising a ring laser gyro and accelerometers to determine pitch and roll information. As the case study is based on a retrofit, it has been assumed that existing IRUs have been retained. Written to supplement not replace the content of the advisory material to these regulations e.
Covers the effect of design, manufacturing, and maintenance errors and the effects of common component errors Evaluates the malfunctioning of multiple aircraft components and the interaction which various aircraft systems have on the ability of the aircraft to continue safe flight and landing Presents and defines a case study an aircraft modification program and a safety strategy in the second chapter, after which each of the following chapters will explore the theory of the technique required and then apply the theory to the case study, In Aircraft Failure Assessments: A Practical Guide for System Safety , the author with the help of co-authors presents a practical guide for the novice safety practitioner in the more specific area of assessing aircraft system failures to show compliance to regulations such a FAR A case study and safety strategy defined in chapter 2 provides the continuity throughout each chapter, and shows the reader how to bring the whole Safety Assessment together in a logical and efficient manner.
Covers the effect of design, manufacturing and maintenance errors and the effects of common component errors Evaluates the malfunctioning of multiple aircraft components and the interaction which various aircraft systems have on the ability of the aircraft to continue safe flight and landing Presents and defines a case study an aircraft modification programme and a safety strategy in the 2nd chapter, after which each of the following chapters will explore the theory of the technique required and then apply the theory to the case study Duane Kritzinger - Aircraft System Safety : Assessments for Initial Airworthiness Certification download DJV, FB2, DOC Each of the forty-nine types of aircraft is accompanied by a brief biography together with tables of the most important marks and their specifications, engine, span, length, height, weight, crew number, maximum speed, service ceiling, normal range and armament.
- The Senedjemib Complex, Part 1!
- Aircraft System Safety () | Aircraft System Safety!
- Looking for other ways to read this?.
- The Book of Joan: Tales of Mirth, Mischief, and Manipulation!
- The Dawning of Power: Young Adult Epic Fantasy Bundle (The World of Godsland Bundle Series Book 1).
- Water Management in Ancient Greek Cities.
- Wet-Steam Turbines for Nuclear Power Plants.
- Aircraft System Safety - Assessments for Initial Airworthiness Certification (Paperback).
- Aircraft System Safety: Assessments for Initial Airworthiness Certification.
Spara som favorit. Skickas inom vardagar. Laddas ned direkt. Aircraft System Safety: Assessments for Initial Airworthiness Certification presents a practical guide for the novice safety practitioner in the more specific area of assessing aircraft system failures to show compliance to regulations such as FAR A case study and safety strategy beginning in chapter two shows the reader how to bring safety assessment together in a logical and efficient manner.
Written to supplement not replace the content of the advisory material to these regulations e. Covers the effect of design, manufacturing, and maintenance errors and the effects of common component errors Evaluates the malfunctioning of multiple aircraft components and the interaction which various aircraft systems have on the ability of the aircraft to continue safe flight and landing Presents and defines a case study an aircraft modification program and a safety strategy in the second chapter, after which each of the following chapters will explore the theory of the technique required and then apply the theory to the case study.