chapter-1 introduction to aircraft drawing

KKAE1023 - Aircraft Drawing

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CHAPTER 1 INTRODUCTION TO AIRCRAFT DRAWING

General Learning Obtectives

1. Having general knowledge of the engineering drawing, the purposes and types of drawing that are used in aeronautics engineering.

Specific Learning Objectives

1. To explain the purposes of engineering drawing and its current technology

2. To explain about the authority of engineering drawing and its organization

3. To have knowledge in types of drawing generally that is used in aeronautical engineering discipline.

1.1 The Purposes of The Drawing

From the early days of aviation, development of aircraft, aircraft engines, and

other components relied heavily on aircraft drawings. For most of the 20th

century, drawings were created on a drawing board with pen or pencil and paper. However, with the introduction and advancement of computers in the

later decades of the 20th century, the way drawings are created changed

dramatically. Computers were used not only to create drawings, but they were

being used to show items in virtual reality, from any possible viewing angle. Further development saw computer software programs with the capability of

assembling separately created parts to check for proper fit and possible

interferences. Additionally, with nearly instantaneous information sharing

capability through computer networking and the Internet, it became much easier

for designers to share their work with other designers and manufacturers

virtually anytime, anywhere in the world. Using new computer controlled

manufacturing techniques, it literally became possible to design a part and have

it precisely manufactured without ever having it shown on paper. New terms and

acronyms became commonplace. The more common of these terms are:

Computer Graphics drawing with the use of a computer,

Computer Aided Design Drafting (CADD) where a computer is used in the design and drafting process,

Computer Aided Design (CAD) where a computer is used in the design of a product,

Computer Aided Manufacturing (CAM) where a computer is used in the manufacturing of a product, and

Computer Aided Engineering (CAE) where a computer is used in the engineering of a product.


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As computer hardware and software continue to evolve, there continues to be a

greater amount of CAE done in less time at lower cost. In addition to product

design, some of the other uses of CAE are product analysis, assembly,

simulations and maintenance information. [Figure 1.1]

Figure 1.1 Computer graphics work station.

The purpose of an engineering drawing is to record and convey the designer's

requirements The drawing must therefore, include sufficient information to

enable production planning, manufacture, assembly, testing and inspection of

the particular component or assembly to be carried out. So that there can be no

misinterpretation of drawings, it is essential that both the person preparing the

drawing and the person using the drawing should have a knowledge of the

terms, symbols, abbreviations, and methods of presentation.

Drawings and prints are the link between the engineers who design an aircraft

and the workers who build, maintain, and repair it. A print may be a copy of a

working drawing for an aircraft part or group of parts, or for a design of a

system or group of systems. They are made by placing a tracing of the drawing

over a sheet of chemically treated paper and exposing it to a strong light for a

short period of time. When the exposed paper is developed, it turns blue where

the light has penetrated the transparent tracing. The inked lines of the tracing,

having blocked out the light, show as white lines on a blue background. Other

types of sensitized paper have been developed; prints may have a white

background with colored lines or a colored background with white lines.

Drawings created using computers may be viewed as they appear on the

computer monitor, or they may be printed out in hard copy by use of an ink jet or laser printer. Larger drawings may be printed by use of a plotter or large

format printer. Large printers can print drawings up to 42 inches high with

widths up to 600 inches by use of continuous roll paper. [Figure 1.2]


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Figure 1.2 Large format printer.

This course gives general guidance on the various aspects of engineering

drawings and should be considered in conjunction with any special methods

used by the design office responsible for a particular drawing. This chapter is

not intended as a standard for drawing offices, but should be regarded as a

general guide to drawing procedures and interpretation.

1.2 The Authority of the Drawing

Civil aircraft manufactured in the United Kingdom are manufactured from parts

and components which have been manufactured to approved drawings. Design

drawings and associated documents are normally produced by an organisation

which has been approved by EASA or the Civil Aviation Authority, in

accordance with European Union Commission Regulation 170212003 or British

Civil Airworthiness Requirements (BCAR), as appropriate.

The requirements prescribe that all calculations on which the airworthiness of an

aircraft depends, must be independently checked. Thus the design drawing itself

is subject to a system of inspection, as are the parts produced to its requirements.

Drawings are used by Purchasing Departments, Production Engineers, Planners,

Inspectors, and personnel engaged on the manufacture and assembly of

components. A drawing must therefore, contain all the necessary dimensions,

limits of accuracy, classes of fit, material specifications and any other

information likely to be required by any of the departments concerned, so that

the user can carry out their respective responsibilities without reference back to

the Design Department.

Any deviation from the approved drawings or associated documents during

manufacture, must be approved by EASA or the CAA, as appropriate. During

overhaul, modification, maintenance and repair, the Approved Organisation, or

the appropriately licensed engineer, must ensure that all replacement parts, or

repairs carried out, are in accordance with the approved drawings and associated

documents.


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1.3 General Types of Drawing

Four types of drawings are recommended;

Single-part (unique parts or assemblies),

Collective (parts or assemblies of essentially similar shape, but of different dimensions),

combined (a complete assembly including all individual parts on a single drawing), and

constructional (an assembly drawing with sufficient dimensional and other information to describe the component parts of a manufacture).

A complete set of drawings for an aircraft and any documents or specifications

referenced on the drawings, present a complete record of the information

required to manufacture and assemble that aircraft. They also form part of the

inspection records. The manner in which a set of aircraft drawings is arranged,

enables any particular component, dimension, procedure or operation, to be

traced.

A main 'general arrangement' drawing of the aircraft and 'general arrangement'

drawings of the main assemblies and systems are provided. These drawings

usually contain overall profile particulars only, with locations and references of

the associated main assembly and installation drawings; they also provide a

guide to the identification of drawing groups used by the particular design

organisation.

Main assembly drawings may also contain profile particulars only, but will

include the information required for the assembly of individual parts of sub-

assemblies. The sequence of assembly is given where appropriate, but the

information contained in single part or subassembly drawings, is not repeated.

Parts as such are referenced, but in the case of subassemblies, only the sub-

assembly will be referenced and not its individual parts.

Installation drawings are issued to clarify the details of extemal dimensions and

attitudes of components, locations, adjustments, clearances, settings,

connections, adaptors, and locking methods between components and

assemblies.

Sub-assembly drawings are issued to convey specific information on the

assembly of component parts. When the method of assembly entails welding, or

a similar process, the drawing will include details of any heat treatment or anti-

corrosive treatment that may be necessary. Sub-assembly drawings are

sometimes issued in connection with spares

provisioning and also in cases where assembly would be difficult without special

tools, jigs or techniques.

Drawings of individual parts contain all the information necessary to enable the

parts to be manufactured to design requirements. The material specification,

dimensions and tolerances, machining details and surface finish, and any

treatment required, will all be specified on the drawings


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1.3.1 Detail Drawing

A detail drawing is a description of a single part, describing by lines, notes, and

symbols the specifications for size, shape, material, and methods of manufacture

to be used in making the part. Detail drawings are usually rather simple; and,

when single parts are small, several detail drawings may be shown on the same

sheet or print. (See Figure 1.3)

Figure 1.3 Detail drawing

1.3.2 Assembly Drawing

An assembly drawing is a description of an object made up of two or more parts.

Examine the assembly drawing Figure 1.4. It describes the object by stating, in a

general way, size and shape. Its primary purpose is to show the relationship of

the various parts. An assembly drawing is usually more complex than a detail

drawing, and is often accompanied by detail drawings of various parts.

Figure 1.4 Assembly Drawing


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1.3.3 Installation Drawing

An installation drawing is one which includes all necessary information for a

part or an assembly in the final installed position in the aircraft. It shows the

dimensions necessary for the location of specific parts with relation to the other

parts and reference dimensions that are helpful in later work in the shop. (See

Figure 1.5)

Figure 1.5 Installation Drawing

1.4 Diagrams

A diagram may be defined as a graphic representation of an assembly or system,

indicating the various parts and expressing the methods or principles of

operation.

There are many types of diagrams; however, those with which the aviation

mechanic will be concerned during the performance of his or her job may be

grouped into four classes or types: (1) installation, (2) schematic, (3) block, (4)

wiring, and (5) Component location diagrams

1.4.1 Installation Diagram

Figure 1.6 is an example of an installation diagram. This is a diagram of the

installation of the flight guidance control components of an aircraft. It identifies

each of the components in the systems and shows their location in the aircraft.

Each number (1, 2, 3, and 4) on the detail shows the location of the individual

flight guidance system components within the cockpit of the aircraft. Installation

diagrams are used extensively in aircraft maintenance and repair manuals, and

are invaluable in identifying and locating components and understanding the

operation of various systems.


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Figure 1.6 Example of installation diagram (flight guidance

components).

1.4.2 Schematic Diagram

Schematic diagrams do not indicate the location of individual components in the

aircraft, but locate components with respect to each other within the system.

Figure 2-19 illustrates a schematic diagram of an aircraft hydraulic system. The

hydraulic pressure gauge is not necessarily located above the landing gear

selector valve in the aircraft. It is, however, connected to the pressure line that

leads to the selector valve.

Schematic diagrams of this type are used mainly in troubleshooting. Note that

each line is coded for ease of reading and tracing the flow. Each component is

identified by name, and its location within the system can be ascertained by

noting the lines that lead into and out of the unit.


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Schematic diagrams and installation diagrams are used extensively in aircraft

manuals.

Figure 1.7 Aircraft hydraulic system schematic.

Coloured diagrams generally are not used in maintenance manuals, but a system

of hatching and shading is normally used to indicate how the system functions.

Another typical schematic diagram (refer to Figure 1.8), is used to give an

overview of the complete aircraft system so that maintenance and diagnosis can

be initiated.


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Figure 1.8 A typical schematic diagram.

1.4.3 Block Diagram

Block diagrams [Figure 1.9] are used to show a simplified relationship of a more

complex system of components. Individual components are drawn as a rectangle

(block) with lines connecting it to other components (blocks) that it interfaces

with during operation.

Figure 1.9 Block Diagram

1.4.4 Wiring Diagram

Wiring diagrams [Figure 1.10] show the electrical wiring and circuitry, coded

for identification, of all the electrical appliances and devices used on aircraft.

These diagrams, even for relatively simple circuits, can be quite complicated.

For technicians involved with electrical repairs and installations, a thorough

knowledge of wiring diagrams and electrical schematics is essential.


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Figure 1.10 Wiring diagram.

1.4.5 Component Location Diagrams

In a Component Location Diagram (refer to Figure 1.11), components, within a

specific system, are shown as they actually appear, and not as symbols or as

"cut-aways".

This simplifies understanding of the overall system operation.

Figure 1.11 A typical component location diagram.


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1.5 Flowcharts

Flowcharts are used to illustrate a particular sequence, or flow of events.

1.5.1 Troubleshooting Flowchart

Troubleshooting flowcharts are frequently used for the detection of faulty

components. They often consist of a series of yes or no questions. If the answer

to a question is yes, one course of action is followed. If the answer is no, a

different course of action is followed. In this simple manner, a logical solution to

a particular problem may be achieved. Another type of flowchart, developed

specifically for analysis of digitally controlled components and systems, is the

logic flowchart.

Figure 1.12 A typical troubleshooting flowchart.

1.5.2 Logic Flowchart

A logic flowchart [Figure 1.13] uses standardized symbols to indicate specific

types of logic gates and their relationship to other digital devices in a system.

Since digital systems make use of binary mathematics consisting of 1s and 0s,

voltage or no voltage, a light pulse or no light pulse, and so forth, logic

flowcharts consist of individual components that take an input and provide an

output which is either the same as the input or opposite. By analyzing the input

or multiple inputs, it is possible to determine the digital output or outputs.


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Figure 1.13 Logic flowchart.

HALAMAN PENGESAHANTABLE OF CONTENTSTABLE OF FIGURESLIST OF TABELSCOURSE DESCRIPTIONDIRECTION OF USECHAPTER 1 INTRODUCTION TO AIRCRAFT DRAWING1.1 The Purposes of The Drawing1.2 The Authority of the Drawing1.3 General Types of Drawing1.3.1 Detail Drawing1.3.2 Assembly Drawing1.3.3 Installation Drawing

1.4 Diagrams1.4.1 Installation Diagram1.4.2 Schematic Diagram1.4.3 Block Diagram1.4.4 Wiring Diagram1.4.5 Component Location Diagrams

1.5 Flowcharts1.5.1 Troubleshooting Flowchart1.5.2 Logic Flowchart

CHAPTER 2 COMMON AERONAUTICAL AND OTHERS STANDARD2.1 International Organisation for Standardisation (ISO)2.2 Military Standard (MS)2.3 Air Force and Navy (AN)2.4 National Aerospace Standard (NAS)2.5 National Standards2.5.1 Standar Nasional Indonesia (SNI)2.5.2 British Standards (BS)2.5.3 American National Standard Institute (ANSI)2.5.4 Deutsches Institute fuer Normung (DIN)2.5.5 Japanese Industrial Standards (JIS)

2.6 Implementation of Standard in Technical Drawing2.6.1 Standard Media2.6.2 Letters and Numberes2.6.3 Line Types2.6.4 Scales2.6.5 Title Block2.6.6 Station Numbers and Location Identification on Aircraft

CHAPTER 3 METHODS OF DRAWING REPRESENTATION3.1 Technical Sketching3.1.1 Computer Aided Design (CAD) Tools3.1.2 Traditional Tools3.1.3 Freehand Sketching Tools

3.2 Sketching Technique3.2.1 Seeing, Imaging, Representing3.2.2 Contour Sketching3.2.3 Straight Lines3.2.4 Curved Lines

3.3 Propotions and Construction Lines3.4 Introduction to Projections3.4.1 Isometric Pictorials3.4.2 Creating an Isometric Sketch from a Three-View Drawing3.4.3 Isometric Ellipses3.4.4 Multiview Projections

3.5 Multiview Sketching Technique3.5.1 Line Conventions3.5.2 Conventional Practices for Circles and Arcs

3.6 Multiview Sketches3.6.1 One-View Sketches3.6.2 Two-View Sketches3.6.3 Three-View Sketches

3.7 Perspective Projection

CHAPTER 4 ADDITIONAL DRAWING VIEWS (SECTION, DETAIL AND AUXILIARY)4.1 Section View4.2 Detail View4.3 Auxiliary View4.4 Exploded View

CHAPTER 5 2D CAD TOOLS: BASIC AUTOCAD5.1 AutoCAD User Interface and Commands5.2 Coordinate Systems5.3 Common Drawing Tools5.4 Common Modifying Tools5.5 Text and Symbols5.6 Dimensions and Tolerances5.7 Blocks and Catalogues5.8 Printing/Plotting

CHAPTER 6 DIMENSIONING AND TOLERANCING6.1 Dimensioning6.2 Machining and Surface Finish (Please refer to ISO)6.3 Abbreviations and Symbols6.4 Process and Identification Markings6.5 Conventional Representations6.6 Allowance6.7 Dimension Tolerance6.7.1 Unilateral and Bilateral Tolerances6.7.2 Baseline and Continued Tolerances

6.8 Geometric Tolerances

CHAPTER 7 FITS AND CLEARANCES7.1 Drill Sizes for Holes7.1.1 Classes of Fit7.1.2 Standards of Fits and Clearances7.1.3 Newall System7.1.4 British Standards BS 4500 System7.1.5 BS 4500 Basic Hole System7.1.6 BS 4500 Basic Shaft System7.1.7 BS 4500 Metric Tolerances7.1.8 Basic Hole Method - Metric7.1.9 Exercise in BS 4500 System

7.2 Ovality, Bow and Twist7.2.1 Schedule of Fits and Clearances7.2.2 Limits for Wear7.2.3 Limits for Ovality7.2.4 Limits for Bow7.2.5 Limits for Twist

CHAPTER 8 READING AND CONSTRUCTING WORKING DRAWING8.1 Basic Concept8.2 Working Drawing8.2.1 Detail Drawing8.2.2 Assembly Drawing8.2.3 Part Number8.2.4 Drawing Number8.2.5 Title Block8.2.6 Part Lists8.2.7 Part Identification8.2.8 Revision Block8.2.9 Scale Specifications8.2.10 Tolerance Specifications8.2.11 Engineering Change Orders (ECOs)

CHAPTER 9 OTHERS DRAWING9.1 Technical Data Presentation9.1.1 Data Visualisation in Engineering and Design9.1.2 Data Visualisation Elements9.1.3 Visualisation Methods9.1.4 Object Rendering9.1.5 Information Integration

9.2 Electronic Drawing9.2.1 Block Diagram9.2.2 Schematic Diagram9.2.3 Wiring and Cabling Diagram9.2.4 Printed Circuit Boad

9.3 Piping Drawing9.3.1 Pipe Types9.3.2 Pipe Connections9.3.3 Pipe Fittings9.3.4 Valves9.3.5 Pipe Drawings9.3.6 CAD-Based Process Plant Design Programs

9.4 Welding Drawing9.4.1 Welding Processes9.4.2 Welded Joint Types9.4.3 Weld Symbols9.4.4 Weld Types9.4.5 Weld Length and Increment9.4.6 Welding Templates9.4.7 Weld Symbols and CAD

CHAPTER 10 MICROFILM, MICROFICHE AND COMPUTERISED PRESENTATIONS10.1 Microfilm10.2 Microfiche10.3 Computer CD-ROM10.4 Supplementary Information

CHAPTER 11 AIR TRANSPORT ASSOCIATION SPECIFICATION ATA 100REFERENCESGBPP (Garis-garis Besar Program Pengajaran)SAP (Satuan Acara Perkuliahan)

chapter-1 introduction to aircraft drawing

Documents

computer graphics drawing

types of drawing

computer networking

computer hardware

drawing board

kkae1023 aircraft drawing

computer aided engineering

computer aided design