Producing aeronautical engineering drawings/models using 3D computer aided techniques
Overview
This standard identifies the competences you need to set up and operate a computer aided drawing (CAD) system to produce three-dimensional aeronautical engineering drawings, in accordance with approved procedures. You will be given a detailed drawing brief or a request for change/modification order, and you will be expected to access these requirements and to extract all necessary information in order to carry out the drawing operations. You will need to select the appropriate equipment and drawing software to use, based on the type and complexity of the drawing functions to be carried out.
You will be expected to set up co-ordinate systems in 3D space, set up the screen into split views to show true 3D (isometric) and plan views. You will then be expected to produce both surface and solid models and understand their differences and applications. You will use boundary modelling techniques as well as graphic primitives to produce your models and will apply Boolean operators to construct the solid models.
Your responsibilities will require you to comply with organisational policy and procedures for working in the drawing office or CAD suite. You will be required to report any problems with the computer hardware, software or drawing procedures that you cannot personally resolve, or that are outside your permitted authority, to the relevant people. You will be expected to work to verbal or written instructions and draught specifications, with a minimum of supervision, taking personal responsibility for your own actions and for the quality and accuracy of the work that you carry out.
Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to applying computer aided drawing procedures. You will understand the 3D CAD system and software used, and its application, and will know about the various tools and techniques used to produce the drawings, in adequate depth to provide a sound basis for carrying out the activities to the required specification.
You will understand the safety precautions required when working with the CAD drawing system. You will be required to demonstrate safe working practices throughout, and will understand the responsibility you owe to yourself and others in the workplace.
Performance criteria
You must be able to:
work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
prepare CAD system for operation using approved procedures
- produce drawings/models that are sufficiently and clearly detailed
- produce drawings/models in the required formats
- use codes and other references that follow the required conventions
- make sure that drawings/models are checked and approved within agreed timescales by authorised people
- ensure that drawings/models are properly registered and stored securely
- ensure that changes are completed as required by organisational procedures
Knowledge and Understanding
You need to know and understand:
- the specific safety precautions to be taken when working with computer systems (to include such items as safety guidance relating to the use of display screen equipment (DSE) and work station environment (such as lighting, seating, positioning of equipment), repetitive strain injury (RSI); the dangers of trailing leads and cables; how to spot faulty or dangerous electrical leads, plugs and connections)
- good housekeeping arrangements (such as cleaning down work surfaces; putting media, manuals and unwanted items of equipment into safe storage; leaving the work area in a safe and tidy condition)
- the set-up and operation of the 3D drawing systems, and the peripheral devices that are used (such as mouse, light pens, digitisers and tablets, printers or plotters, and scanners)
the correct startup and shutdown procedures to be used for the computer systems
the methods and procedures used to minimise the chances of infecting a computer with a virus
the implications if the computer you are using does become infected with a virus and who to contact if it does occur
how to access the specific computer drawing software to be used, and the use of software manuals and related documents to aid efficient operation of the relevant drawing system
- how to deal with system problems (such as error messages received, peripherals which do not respond as expected, obvious faults with the equipment or connecting leads)
- the documentation required for particular applications (such as design briefs, specification sheets, request for change orders)
- types of drawing/models that may be produced by the software
- how to set up the viewing screen to show multiple views of the component to help with drawing creation (to include isometric front and side elevations)
- the national, international and organisational standards and conventions that are used for the drawings
- how to set up the drawing template parameters (such as layers of drawings, scale, paper size, colour set-up, line types, dimension system and text styles)
- the application and use of drawing tools (such as for straight lines, curves and circles; hatching, shading and layers)
- how to access, recognise and use a wide range of standard components and symbol libraries from the CAD equipment
- the applications of different 3D modelling programmes (such as surface, solid and wire frame)
- the different projections used to create 3D drawings (such as isometric, oblique, orthographic, perspective and planometric)
- the application of different co-ordinate measurements used to create 3D drawings (such as Cartesian, spherical and cylindrical)
- the display views that can be used on 3D drawings (such as view co-ordinate geometry and object co-ordinate geometry
- the application and use of drawing tools for surface or solid modelling; how to modify drawings using surface modelling tools or Boolean operators; how to add dimensions and text to drawings
- the need for document control (such as ensuring that completed drawings are approved, labelled and stored on a suitable storage medium, the need to create backup copies and to file them in a separate and safe location away from possible corruption, filing and storing hard copies for use in production)
- the procedures for drawing change notes, trial changes, up-issuing of drawings, modifications, and miscellaneous amendments to drawings
- the relevant sources and methods for obtaining any required technical information relevant to the drawing being produced (such as limits and fits, contraction allowances, bearing selection, surface finish)
- the documentation required for the release/issue of drawing/models
- the principles of engineering manufacturing operations, assembly and installation methods and limitations of the equipment/processes that are used to produce the drawn item (such as machining methods, joining processes, fabrication, casting and forging), and how these can influence the way you present the drawing
- the functionality of the component and its interrelationship with other components and assemblies
- the extent of your own responsibility and to whom you should report if you have problems that you cannot resolve when producing the drawings
Scope/range
Scope Performance
Prepare the CAD system for operation by carrying out all of the following:
- check that all the equipment is correctly connected and in a safe, tested and usable working condition (cables undamaged, correctly connected, safely routed)
- power up the equipment and activate the drawing software
- set up the drawing system to be able to produce the drawing to the appropriate scale
- set up and check that all peripheral devices are connected and correctly operating (such as keyboard, mouse, light pen, digitiser/tablet, scanner, printer, plotter)
- set the drawing datum at a convenient point (where applicable)
- set up drawing parameters (to include layers, lines type, colour, text styles) to company procedures or to suit the drawing produced
- create a drawing template to the required standards, which includes all necessary detail (such as title, drawing number, scale, material, date)
Use three of the following to obtain the necessary data to produce the required drawings/models:
- drawing brief/request
- specifications
- change order/modification request
- regulations
- manuals
- sample component
- calculations
- previous drawings/designs
- sketches
- notes from meetings/discussions
- standards reference documents (such as limits and fits, tapping drill charts, rivet dimensions)
- other specific data
Take into account eight of the following, in relation to the drawing/model being produced:
- function
- cost
- physical space
- quality
- lifetime of the product
- operating environment
- manufacturing method
- tolerances
- interfaces
- ergonomics
- clearance
- safety
- materials
- aesthetics
Carry out all of the following before producing the engineering drawing/model:
- ensure that data and information are complete and accurate
- review the data and information to identify the drawing requirements
- recognise and deal with problems (information based and technical)
Use two of the following 3D modelling tools:
- surface modelling
- solid modelling
- wire frame modelling
Use two of the following co-ordinate measurements to produce 3D models:
- Cartesian
- cylindrical
- spherical
Produce and modify 3D engineering models, using two of the following tools and techniques:
- graphic primitives
- surface modifying tools
- boundary techniques
- Boolean operators
- other specific technique
Produce engineering drawings using two of the following methods of projection:
- isometric
- perspective
- oblique
- planometric
- orthographic
Produce 3D engineering drawings/models for three of the following:
- detailed structural/airframe components (such as stringers, frames, ribs, trays, skins, panels, tanks, brackets)
- sub-assemblies (such as flaps, ailerons, under-floor structures, side structures, cabin roof, avionics cabinets, mission consoles, engine nacelle, windows, galleys, hatches, doors, stairs, trunking/ducting, and bulkheads)
- major assemblies (such as front, rear and centre fuselage sections; floors, wings, fin and tail sections, nose sections, cabins or cockpits)
- mechanical components
- mechanical controls/systems (such as chains and sprockets; cables, pulleys and turnbuckles; levers and linkages; control rods; pivots and bell cranks; struts and stays; locks and jacks; servo actuators; tie rods, torque tubes and trim wheels)
- fluid power equipment/systems (such as hydraulic, vacuum, pneumatic)
- avionic/electrical equipment/systems (such as avionic cabinets, mission consoles, VDU display units)
- development models
- other specific structures
Produce drawings which include nine of the following:
- straight lines
- insertion of standard components
- hidden detail
- dimensions
- symbols and abbreviations
- hatching and shading
- angular surfaces
- curved surfaces
- parts lists
- text
- circles or ellipses
- other specific detail
Save and store drawings/models in appropriate locations, to include carrying out all of the following:
- ensure that your drawing has been checked and approved by the appropriate person/s
- ensure that the drawing is ready for exporting to the next manufacturing stage
- check that the drawing is correctly titled and referenced
- save the drawing to an appropriate storage medium
- create a separate backup copy and place it in safe storage
- produce a hard copy printout of the drawing for file purposes
- register and store the drawings in the appropriate company information system
- record and store any changes to the drawings in the appropriate company information system
Produce drawings/models in compliance with one of the following:
- CAD software standards
- Civil Aviation Authority (CAA)/European Aviation Safety Agency (EASA)
- Ministry of Defence (MoD)
- Military Aviation Authority (MAA)
- Aerospace Quality Management Standards (AS)
- Federal Aviation Authority (FAA)
- BS, ISO or BSEN standards and procedures
- customer standards and requirements
- company standards and procedures
- aircraft manufacturer's requirements
Scope Knowledge
Values
Behaviours
You will be able to apply the appropriate behaviours required in the workplace to meet the job profile and overall company objectives, such as:
- strong work ethic
- positive attitude
- team player
- dependability
- responsibility
- honesty
- integrity
- motivation
- commitment