Airworthiness MSc

• Dr Simon Place

To provide a fundamental knowledge of the requirements for airworthiness in aircraft design, production, operation and maintenance.

• Introduction to Airworthiness
• Air Law
• Certification Process, including the safety assessment of aircraft systems
• Airworthiness Lessons learned - Review of significant accidents
• Production Organisation Approval (POA)
• Maintenance and Operations Approvals
• Continuing Airworthiness management
• Engine certification
• Application of Safety Management Systems in the field of airworthiness
• Human Factors in maintenance
• Incident reporting and Service Difficulty Reports (SDRs)
• Engine failure modes
• FAA certification of non-US products
• Current airworthiness challenges.

• Dr Simon Place

To familiarise students with the various approaches to the problems of assessing the safety of increasingly complex aircraft systems.

• Requirements for safety assessment as part of regulatory approval and continued airworthiness process
• Development of requirements for safety assessment, FAR and EASA CS25-1309
• Introduction to probability methods and safety analysis techniques
• Common mode failures
• Fault tree analysis, dependence diagrams and Boolean algebra for quantification of system reliability
• Reliability analysis using Weibull distribution
• Zonal safety analysis (ZSA) and Particular Risk Analysis (PRA)
• Failure Mode and Effect Analysis (FMEA)
• Typical safety assessment for a stall warning and identification system
• Certification maintenance requirements

On successful completion of the module, you will be able to:

• Explain the theory behind each technique for safety assessment, including the strengths and weaknesses of each one
• Evaluate and apply the technique(s) which is most appropriate for the system under consideration
• Differentiate between the various stages of safety assessment in the development of an aircraft or system
• Illustrate the issues to be faced in the certification of new systems and aircraft.

• Cengiz Turkoglu

To provide students with the fundamentals of the disciplines associated with the management of aircraft maintenance and engineering.

• Maintenance Programme Development – balancing of technical requirements and operational priorities; Maintenance Steering Group 3 process.
• Optimisation of maintenance - Outsourcing/In House Maintenance; Application of Lean principles to Maintenance operations; Maintenance planning; Maintenance costs.
• Human Factors in Aircraft Maintenance - Error types; Classification systems; Maintenance Error Management System; Maintenance Error Decision Aid (MEDA) & other resources.
• Logistics and supply chain management.
• Linkages between manufacturer, operator and maintenance organisation.
• Continuing airworthiness management and Regulatory aspects (EASA Part M).
• Health and usage monitoring, engine condition monitoring etc.

• Dr Wenli Liu

To familiarise students with fatigue and damage tolerance analysis techniques and their application to aircraft structural design by instruction, investigation and example.

BASIC PRINCIPLES
Introduction to Fatigue Design Philosophies
Outline of the fatigue failure process; Approaches to design against fatigue; safe-life, fail-safe, and damage tolerance; Fatigue life calculation requirements

Regulatory background
Requirements for fatigue and damage tolerant design for civil & military aircraft; Chronology of accidents in relation to aircraft design approach; Evolution of requirements; Focus on Large Aeroplanes and Rotorcraft

Fatigue Analysis
S-N curve approach: the traditional fatigue analysis approach; e-N curve approach for low cycle fatigue; mean stress effect; Palmgren-Miner’s cumulative damage model.
Crack Initiation Life Prediction: Notch effect; Neuber’s approach; calculation of crack initiation life at notch root and fastener holes; Worked examples of techniques.
Aircraft fatigue loading spectrum: atmospheric turbulence, manoeuvre, landing and ground loads; determination of cumulative frequency load distribution. Cycle counting methods.

Linear Elastic Fracture Mechanics
Basic theory of Linear Elastic Fracture Mechanics; crack tip stress intensity factor; strain energy release rate; fracture toughness; R-curve; fracture criterion; plane stress and plane strain conditions; plastic zone at crack tip; calculation of residual strength.
Crack growth under cyclic loading; crack closure effect; overload retardation effect; load sequence effects; predicting crack growth life; Worked examples.

Computer tools for life assessment – workshop session using the AFGROW package for crack growth prediction

Residual strength calculation of stiffened panels
Short crack growth and the limitations of fracture mechanics

Material selection
Role of strength level and toughness; effect of corrosion on fatigue;
Comparison of response behaviour of Composites and Metals to cyclic loading.

APPLICATIONS

Inspection considerations.
Methods to establish thresholds; Requirements for NDT capability;
Probability of detection versus crack length
Fatigue & fracture analysis of commuter aircraft structures
Review of round robin exercise applying analysis techniques to actual aircraft structural components

Ageing aircraft structures
Multiple-site damage phenomenon; Effect of ageing; Effect of MSD on lead crack residual strength; Equivalent initial quality flaw size; Real examples demonstrated on several aircraft types; Onset of widespread fatigue damage; Inspection frequency for each Principle Structural Element; Limit of Validity, Current regulatory approach for in-service aircraft.

Repair to damage tolerant aircraft
Techniques for the design of damage tolerant repairs;
Examples of in service repairs and regulatory lessons learned;
Use of cold expansion for life enhancement

• Professor Vassilios Pachidis

To provide an opportunity to acquire a good general understanding of the principles of gas turbine design and performance appropriate to both manufacturing and user industries

• Gas turbine fundamentals
o Fundamental fluid mechanics applied to the gas turbine engine.
o Properties of gases including entropy and viscosity.
o Reynolds number effect and qualitative treatment of boundary layer behaviour.
o Adiabatic and isentropic flow, static and stagnation conditions. Mass flow functions and choking.

• Gas turbine performance
o An introduction to ideal cycles.
o Component and cycle efficiencies and their relationship with specific consumption and air miles per gallon.
o Design-point analysis of turbojet, turboprop and turbofan (bypass) cycles.
o Influence of pressure ratio, peak temperature, by-pass ratio and flight conditions on specific thrust and fuel consumption.
o Use of non-dimensional groupings.

• Gas turbine applications
o Comparison of behaviour of different engine types; choice of engine parameters for given duty.

• Axial compressor design and performance
o Overall problems of diffusing airflows.
o The overall compressor characteristic, real and ideal, stall and choke, the surge line, running line, effect of changes in inlet pressure and temperature.
o Off-Design performance, use of variable IGV's, air bleed, multi-spooling.
o Choice of annulus geometry, tip speed, etc.

• Axial turbine design and performance.
o Overall problems of expanding airflows. The importance of passage shape. Choice of blade profile shape, prescribed velocity distribution. The axial turbine stage, velocity triangles, reaction, stage loading and flow coefficients; Limiting values. Design for maximum power, effect of Mach number, effect of choking and changes of inlet temperature and pressure. Factors affecting efficiency, efficiency correlations. Choice of design point according to application.

• Combustion systems
o The following topics are treated at an introductory level:
o Burning velocity; effects of pressure, temperature and turbulence.
o Performance criteria of combustion chambers; combustion efficiency, stability and ignition performance, temperature traverse quality.
o Fuel injection methods; spray injection, vaporising tubes, airblast atomisers.
o Gaseous pollutants, mechanism of production of CO, Nox, UHC and aldehydes. Carbon formation and exhaust smoke, use of alternative and residual fuels in gas turbines.
o Combustor cooling.

• Fuels Technology
o Hydrocarbon fuel molecular structure and behaviour.
o Conventional petroleum fuel types and preparation.
o Laboratory test methods and results.
o Significance of test results in fuel handling and combustion performance.
o Aviation fuel specifications, and reasons for recent amendments.
o Current problems: thermal stability, linear temperature, smoke formation, etc.
o Expected changes in fuel quality.
o Alternative fuels for use in the short and long term.

• Mechanical integrity
o Origin of loads on gas-turbine components.
o Factors and strength criteria for proof, ultimate, creep, fracture and fatigue cases.
o Integrity of specific components such as discs, blades, shafts, combustion chambers, casings, flanges, etc.
o Cumulative creep.
o Fatigue and Fracture Mechanics -. Effects of cyclic loading.
o Paris Law, mean stress effects.
o Types of vibration encountered in the gas turbine.
o Blade modes of vibration, including centrifugal and thermal effects.
o Methods of determining natural frequencies.
o Production of frequency diagram and methods of overcoming vibration problems.
o Critical speeds of shafts and alleviation by means of squeeze-film damper bearings.

• Design substantiation and Certification
o Current regulatory requirements [European and USA] for aerospace.
o Nature and extent of substantiation and validation testing.
o The role of analysis.
o Examples of typical design pitfalls.

On successful completion of this module a student should be able to:

1. Make a reasoned selection of the major performance parameters according to engine application.
2. Understand the impact on design and performance of the joint constraints of mechanical and thermal issues and the need for adequate off- design performance.
3. Understand the statutory design requirements and the extent of testing and analysis required for aero-engine certification.
4. Demonstrate knowledge of the design issues that can effect airworthiness.

To provide students with the fundamental knowledge and skills required to manage operational safety within the aviation industry.

• The fundamentals of a Safety Management System, and introduction to associated guidance material provided by the International Civil Aviation Organisation (ICAO) and other State safety regulatory bodies
• Safety data, safety information and analyses, including reporting systems, investigation and Flight Data Monitoring (FDM)
• Hazard identification and risk management, including an introduction to Enterprise Risk Management (ERM)
• Safety performance and safety health, including guidance on audits and safety promotion
• Safety organisations, including guidance on effective management of safety teams

On completion of this module the student will be able to:

• Describe the fundamental concepts behind Safety Management Systems (SMS), as defined by ICAO, UK CAA, CASA and Transport Canada
• Select and implement techniques for the identification, quantification and management of hazards and risks
• Critically assess strategies for developing and enhancing safety culture including the role of leadership, structure and reporting systems
• Identify techniques for measuring safety performance.

To expand the students’ knowledge of airframe systems, their role, design and integration. In particular, to provide students with an appreciation of the considerations necessary when selecting aircraft power systems and the effect of systems on the aircraft as a whole.

• Introduction to Airframe Systems
• Systems Design Philosophy and Safety
• Aircraft Secondary Power Systems
• Aircraft Pneumatics Power Systems
• Aircraft Hydraulics Power Systems
• Aircraft Electrical Power Systems
• Aircraft Emergency Systems
• Flight Control Power Systems
• Aircraft Environmental Control
• Aircraft Icing and Ice Protection Systems
• Aviation Fuels and Aircraft Fuel Systems
• Engine Off-Take Effects
• Fuel Penalties of Systems
• Ageing of Aircraft Systems
• Advanced and Possible Future Airframe Systems.

• Dr Panagiotis Laskaridis

To familiarise course members with the common problems associated with the mechanical design and lifting of the gas turbine engine and its components

Loads / forces / stresses in gas turbine engines
The origin of loads / forces / stresses in a gas turbine engine such as loads associated with: rotational inertia, flight, precession of shafts, pressure gradient, torsion, seizure, blade release, engine mountings within the airframe and bearings. Discussion of major loadings associated with the rotating components and those within the pressure casing including components subject to heating.

Failure criteria
Monotonic failure criteria: proof, ultimate strength of materials. Theories of failure applied to bi-axial loads. Other failure mechanisms associated with gas turbine engines including creep and fatigue. Fatigue properties including SN and RM diagrams, the effect of stress concentration, mean stress etc. The double Goodman diagram technique applied to fatigue life calculations of gas turbine components. Cumulative fatigue, multi-axial fatigue, strain based methods for the calculation of low cycle fatigue life. The rainflow cycle counting technique and its application to the calculation of fatigue life. Methods of calculating creep life using the the Larson- Miller Time-Temperature parameter. Lifing philosophies applied to gas turbine critical components. Introduction to fracture mechanics and its application to the Damage Tolerance Lifing Philosophy.

Applications
The design of discs and blades. Illustration of the magnitude of stresses in conventional axial flow blades by means of a simple desk-top method to include the effect of leaning the blade. The stressing of axial flow discs by means of a discretised hand calculation which illustrates the distribution and relative magnitude of the working stresses within a disc. The design of flanges and bolted structures. Criteria for leakage through a flanged joint and failure of the joint from fatigue.

Blade vibration
Introduction to vibration and vibration measurement. Resonances. Sources of blade excitation including stationary flow disturbance, rotating stall and flutter. Vibration of bladed assemblies. Derivation of the Campbell diagram from which troublesome resonances may be identified. Methods for dealing with resonances. Vibration monitoring.

Turbomachine rotordynamics
Shaft dynamics and bearings. Critical speeds / mode shapes and their relevance to gas turbine engines. The effect of bearing / support stiffness on critical speed.

Regulatory requirements
European airworthiness standards related to engine and component integrity. Testing, validation and certification issues. Case studies.

On successful completion of this module a student should be able to:

1. Demonstrate an understanding of the design requirements of gas turbine turbomachinery components.
2. Perform straightforward calculations involving bi-axial monotonic loads on gas turbine rotating components and to apply appropriate failure criteria.
3. Estimate the life of a gas turbine blade or shaft subject to two cyclic amplitudes of fatigue loading.
4. Perform hand calculations to estimate the stresses in turbomachine blades and discs
5. Calculate the low order natural frequencies of turbomachine blades and use them in conjunction with Campbell diagrams to suggest solutions to problems with dangerous resonances in the running range of the engine.
6. Design a flanged joint making allowances for leakage and fatigue failure.
7. Demonstrate an understanding of the relevant regulatory requirements and the means of substantiation for aerospace gas turbine component integrity.

• Dr Simon Place

To familiarise Course Members with the reliability analysis of data from tests and service records, and methods of evaluating system reliability as part of design

• Outline of the various means of performing the reliability analysis of components and systems.
• Requirements for safety and reliability analysis as part of Regulatory Approval process.
• Analysis of Failure Data - Negative exponential and Weibull probability distributions; Data analysis and ranking methods; Confidence intervals; Normal, log-normal distributions.
• Systems - Conventional representation; Series-parallel methods; Decomposition techniques; Path and cut sets; Reliability of maintained systems; Failure mode effect and criticality analysis; Fault Tree Analysis; Markov methods.
• Applications - Reliability prediction during project design and development; In-service reliability and service policy development

On successful completion of this module a student should be able to:
1. Understand and illustrate the concepts of reliability analysis.
2. Distinguish between the different methods for analysing the reliability of components and systems.
3. Use the most appropriate analysis technique when presented with failure data based on component and/or system in-service information.
4. Outline a quantitative and qualitative analysis of different component and system designs.

• Peter McCarthy

The process of accident investigation will be considered as a whole from notification and disaster response through evidence collection and analysis to the preparation of a final report and recommendations for change. Different approaches will be considered including ‘no-blame’, criminal and coronial investigations with particular emphasis on the role that human factors practitioners can play in the investigation and in dealing with the consequences of an accident and its associated recommendations.

• Accident investigation approaches and response,
• investigation as it relates to safety management systems,
• disaster response and emergency planning,
• on site appraisal and preservation of evidence,
• human factors in investigations,
• witnesses and interviewing,
• cross-cultural issues in accident investigation,
• preparing and managing recommendations. 

 

This module aims to introduce aircraft engine control and to explain the philosophy of jet engine control requirements and systems to gas turbine engineers.

Compressor performance
The difficulty of compressing air; the overall compressor characteristic and its graphical presentation. Running line and surge line. Performance limitations at low rotational speed and low airflow. Design for surge alleviation. The use of variable inlet guide vanes, variable stators, air bleed, multi-spooling.

Axial turbine performance
Physics of expanding gas flows and choking. Performance at maximum flow. Effect of changes in inlet temperature and pressure. The turbine overall performance characteristic and turbine efficiency.

Gas turbine control
Needs and Implementation. The gas turbine is a very complex mechanism that has to operate within many constraints including aerodynamic, mechanical and handling issues. At the same time it also needs to be responsive and operate safely. An explanation will be given on these constraints and how different features such as variable stators, bleed valves and variable area nozzles can be used to implement safe and responsive engine handling. An explanation on component matching and the influence of each control feature on the operation of the engine.

Introduction to fuel systems and fuel pumps
To include the role of the fuel system; fuel properties; typical fuel flows, temperatures, and pressures in the system, descriptions of low pressure first stage pump, high pressure second stage pumps; typical modern control systems.

Airframe Fuel Systems
Low Pressure Engine Fuel Systems. To include typical LP system architecture, fuel pump inlet pressure requirements, the concept of Net Positive Suction Pressure (NPSP), establishing the low pressure pump design points; low pressure first stage pump types; fundamentals of LP pump design.

High pressure engine fuel pumps
Difference between positive displacement and rotodynamic pumps, types of positive displacement pumps; selecting the optimum drive speed; sizing a positive displacement pump; the effect of leakage on pump size and heat rejection; mechanical design considerations; journal bearing design; pointing design and minimizing cavitation erosion damage.

Hydro-mechanical fuel metering
Brief history of fuel control architectures leading to FADEC systems; Functions required by modern FADEC based fuel controls; impact of reliability requirements on modern fuel control architecture; modern fuel control architecture; basic principles of fuel flow; fuel metering; electrical interface devices used on modern fuel controls; engine actuation; demonstration of modern fuel control hardware; fitness for purpose, future trends in fuel control.

Electronic engine control
To include circuit design, mechanical design, software.

Staged Combustion
To include Aircraft emissions, emissions legislation, controlling emissions, fuel control requirements, fuel control, control laws.

Fuel controls for ‘more/all’ electric engines
To include impact of the More/All electric engine on fuel control, positive displacement pump based systems, centrifugal pump based systems, technical challenges.

Airworthiness considerations
European and USA regulatory requirements relevant to certification and substation of engine controls and fuel systems including their installation. Service history, occurrences and case studies

On successful completion of this module a student should be able to:
1. Analyse the control needs and operational issues associated with gas turbines used for aircraft propulsion.
2. Distinguish the objectives of control philosophies systems.
3. Assess jet engine control systems design.
4. Evaluate the different mechanisms that allow the safe and efficient operation of a jet engine.
5. Relate the technology involved to the regulatory framework.

• Professor Kevin Garry

To give a basic knowledge of aerodynamic principles and familiarity with the fundamental characteristics of fluid flow.

• Fluid Properties and Basic Flow Equations.
• Dimensional Analysis and Aerodynamic force.
• Viscosity the Boundary Layer and Skin Friction.
• Vortex Flow and Aerofoil Circulation.
• Finite Low Speed Wings.
• Aerofoil and Wing High Lift Devices.
• Flying Controls.
• Supersonic Flow Characteristics.
• Supersonic Aerofoil Sections.
• Finite Supersonic Wings.
• Transonic Flow Characteristics.
• Theoretical Aerodynamics: Navier Stokes Equations, Vector form of Navier Stokes equations.
• Mathematical properties of PDE’s.
• Solution methodology for initial boundary value problems.
• Other Reduced forms of the Navier Stokes Equations.
• Equation of Continuity: Viscous Stresses - shear and normal.
• Navier-Stokes equations. The viscous flow energy equation.
• Similarity parameters.
• The 2D boundary layer equations - continuity, x and y momentum and energy.
• Analyse experimental aerodynamic data using XFOIL software
• Conduct virtual experiment using lab view

The aim is to provide students with a basic understanding of a broad range of issues associated with aircraft manufacture. The module will cover technical and management topics ranging from strategy and factory planning to composite manufacture.

• Key manufacturing concepts and processes
• Composite manufacture
• Manufacturing planning and control issues
• Lean and cellular manufacturing principles
• Quality management
• Manufacturing systems analysis using factory physics
• Modelling and simulation of manufacturing systems
• Manufacturing cost engineering
• Sustainable manufacturing
• Product introduction and product use/service.

On completion of this module, students will:

• Have a critical awareness of manufacturing systems concepts that will enable them to contribute to the cost-effective manufacture of future aircraft
• Have a comprehensive understanding of the interrelationships between different manufacturing disciplines and how these can contribute to meeting the special challenges of aircraft manufacture
• Be able to apply their acquired knowledge to contribute effectively to Integrated Product Teams representing or taking into account the manufacturing issues related to aerospace product realisation.

The course seeks to provide engineers with knowledge of polymer composite properties and behaviour relevant to their in-service performance durability and maintenance in aircraft structures

Basic principles
Introduction to composite materials comparison of relevant mechanical and service properties to those of metals; manufacturing process and relation of process and constituents to service performance.

Regulatory background
Requirements for fatigue and damage tolerant design in civil and military aircraft as implemented for polymer composite structures. Requirements for rotorcraft and for large fixed wing aircraft.

Structural analysis
Brief summary of methods and techniques for stress analysis and aircraft design using polymer composite materials.

Fatigue analysis
In-plane fatigue and failure processes; stiffness and strength changes under fatigue loading; fatigue notch effects in polymer composite laminates; cycle counting techniques and variable amplitude loading in metallic and polymer composite materials; life assessment and calculation procedures for design against in-plane fatigue.

Delamination crack growth and fracture mechanics
Basic theory of linear elastic fracture mechanics; strain energy release rate; applications to delamination crack growth in polymer composite laminates; delamination crack growth testing under static and fatigue loading; laboratory testing to measure Mode I and Mode II interlaminar fracture toughness (GIC and GIIC); comparison with stress intensity approaches in metallic materials; calculation of delamination behaviour of small samples and of aircraft structures. Damage tolerance issues in composites.

Service degradation processes
Impact damage in polymer composite laminates
Response of polymer composites to out-of-plane impact loading; laboratory testing, effects of velocity, mass and impacting body shape on damage produced; damage morphologies, barely visible impact damage (BVID) concepts; effects of laminate constituents on damage resistance; effects of in-plane loading on impact damage growth and laminate strength; compression and fatigue after impact; design against impact damage.

Service environment issues
Including response to temperature and humidity; bird strike; in- service damage detection in composite structures; repairs; operator experience with polymer composite aircraft structures. Structural test requirements to prove airworthiness.

On successful completion of this module a student should be able to:
1. Describe the properties and manufacture techniques of polymer composite materials, and of the basic approaches to design with them.
2. Categorise the aircraft service degradation processes of polymer composite laminates involving fatigue, impact loading, temperature and humidity fluctuations.
3. Evaluate the effect aircraft service degradation processes have on strength and durability of the composite.
4. Undertake simple calculations of damage tolerance based on laboratory test data.
5. Formulate structural and coupon sample test requirements to demonstrate the adequacy of the static and fatigue strength and damage tolerance of a composite aircraft structure.
6. Critically appraise the design principles and relate them to structural safety considerations in the appropriate regulatory context, for both new designs and in- service aircraft.

• Dr David Zammit-Mangion

To provide a comprehensive overview of avionics systems and infrastructures.

• Introduction to avionics systems.
• Airborne sensor systems.
• Navigation and communications systems – terrestrial and satellite-based systems, autonomous navigation systems, digital data links.
• Radar – principle of operation, operational modes, radar cross section.
• Displays – head down, head up and helmet mounted displays.
• Avionics systems architectures and integration, databases.
• Flight management and situational awareness systems, air traffic management.
• Military applications – electronic warfare and countermeasures.
• Product design considerations – design standards, fault tolerance and product life cycle.
• Case study – a complete avionics installation.

This module has an additional tutorial inside the cockpit of the large aircraft flight simulator. Students will be able to appreciate the cockpit layout design, understand information displayed to the pilot, and have the opportunity of flying the simulator. This tutorial is intended to enhance the learning process and the knowledge gained.

On successful completion of this module a student should be able to:
1. Demonstrate an understanding of the principles of operation, basic functions and properties of avionics systems.
2. Identify the design and development strategies of avionics systems.
3. Be capable of developing avionics installation requirements in aircraft.

The module aims to provide a broad overview of the nature and management of human error in the aviation maintenance domain. Key theories and frameworks for investigating maintenance human error, contributing factors and effects on operations are introduced. The challenges associated with practical application of currently available safety tools are examined together with the latest strategies to enhance understanding and management of maintenance error. This module does not require previous background in aviation maintenance and engineering.

• The nature of the maintenance environment:This includes both civil and military environments. 

• Maintenance management: Organisation, line and base maintenance, planning, maintenance control, error management systems, shift handover, blame cycle, communication in the workplace, workplace environment, work/job design. Regulatory framework: Legal requirements. EASA/Part 145 Maintenance Human factors.
• Designing for human factors: What can be done by the designer to reduce and mitigate human error. Design philosophies and human-centred design.
• Human error management in maintenance: The benefits and challenges associated with the use and application of reporting systems and safety tools.

On successful completion of this module a student should be able to:

1. describe the regulatory background and the environment within which aviation maintenance takes place Describe the regulatory background and the environment within which aviation maintenance takes place
2. evaluate current methods for maintenance error management (reactive, proactive and predictive)
3. appraise the links between aircraft maintenance and safety
4. analyse ways in which maintenance errors can be reduced at the design stage.

• Dr Alastair Cooke

The aim of this module is to provide an introduction to the performance, stability and control characteristics of a conventional aircraft.

• Air data systems, Standard atmosphere and pressure error measurement.
• Basic aircraft aerodynamics: lift and drag.
• Cruise and climb performance.
• Static equilibrium and trim.
• Longitudinal static stability, trim, pitching moment equation, static margins and manoeuvre margins.
• Lateral-directional trim and static stability.
• Introduction to dynamic stability and modal analysis

• Dr Ioannis Giannopoulos

To introduce students to the techniques of detail stressing as practised in the aerospace industry.

• The structural function of aircraft components. Definition of Limit, Proof and Ultimate loads and Factors for Civil and Military aircraft
• Basic formulas for stress analysis. Stress strain curves for metallic materials. Material equivalents. Concept of Reserve Factors (RF) and Margins of Safety (MS)
• Material data. Design guidelines for mechanically fastened joints. Lugs. Strength of bolted/riveted joints. Usage of approved aerospace components
• Structures under bending and compression. Euler buckling, flange buckling, inter-rivet buckling. Buckling of struts and plates. Shear buckling of webs
• Generalized stress strain curves
• Plastic bending and form factors
• Rivet and bolt group analysis
• Analysis of thin walled structures
• Preparation of a detailed Stressing Report and Reserve Factor summary tables for a classroom exercise to be completed during this module.

• Apply the principals and techniques in stress analysis and airworthiness requirements to size basic aircraft structural components
• Evaluate the strength of a component and determine its ability to support an applied load
• Compare, propose and select metallic materials suitable for use in aircraft structures
• Acquire transferable skills to allow effective communication with company stress engineers.

The aim of this module is to provide students with an understanding of the design of crashworthy aircraft structures and the considerations necessary when designing safe and crashworthy aircraft. The main purpose of crashworthy design is to eliminate injuries and fatalities in mild impacts and minimise them in severe but survivable impacts.

Overview of Aircraft Crashworthiness

• Objectives and Approach
• Regulations
• Human Tolerance
Crash Energy Management

• Structural Collapse
• Collapse of metallic and composite structural components
• Component collapse vs. structural collapse
Introduction to methods for crash analysis

• Hand calculations
• Hybrid analysis methods
• Detailed analysis methods
Role and capability of testing and simulation in the crashworthiness field

• Outline the main priorities and fundamentals of crashworthiness in aircraft in the context of protection in crash events
• Define the requirements for structural components used for impact energy absorption and structural collapse in aircraft
• Describe crashworthiness requirements on major equipment and systems
• Identify relevant regulations for aircraft crashworthy design
• Discuss human tolerance in the context of crashworthiness
• Identify the main experimental and analytical techniques used in design for crashworthiness
• Apply the systems approach in impact energy management to aircraft design
• Use simple approximate calculations on the performance of energy absorption components and structures to assess the crashworthiness of an aircraft structure.