Aircraft Drawings
What is the allowable manufacturing tolerance for a bushing where the outside dimensions shown on the blueprint are: 1.0625 + .0025 -.0003?
*0.0028. The bushing described here has an outside dimension of 1.0625 inch with a tolerance of +0.0025 -0.0003. The bushing could have an outside diameter of anywhere between 1.0622 inch and 1.0650 inch. The tolerance for this part is 0.0028 inch.
Which of the following terms is/are used to indicate specific measured distances from the datum and/or other points identified by the manufacturer, to points in or on the aircraft? 1. Zone numbers. 2. Reference numbers. 3. Station numbers.
*3. Station numbers is a numbering system used on large assemblies for aircraft to locate stations such as fuselage frames. Fuselage Frame-Sta 185 indicates the frame is 185 inches from the datum of the aircraft. The measurement is usually taken from the nose or zero station, but in some instances it may be taken from the firewall or some other point chosen by the manufacturer.
What type of line is normally used in a mechanical drawing or blueprint to represent an edge or object not visible to the viewer?
*A medium-weight dashed line. A medium-weight dashed line is called a hidden line and is used to show an edge or object not visible to the viewer. A medium solid line is used as a visible outline or object line. Alternate short and long light dashes are used to show a center line.
In what type of electrical diagram are images of components used instead of conventional electrical symbols?
*A pictorial diagram. A pictorial diagram is similar to a photograph. It shows an object as it appears to the eye, but is not satisfactory for showing complex forms and shapes.
What type of diagram shows the wire size required for a particular installation?
*A wiring diagram. An electrical wiring diagram shows the wire size required for a particular installation.
A drawing in which the subassemblies or parts are shown as brought together on the aircraft is called
*An installation drawing. An installation drawing is one in which all of the parts and subassemblies are brought together.
What should be the first step of the procedure in sketching an aircraft wing skin repair?
*Block in the views. In making a sketch of a repair, the first thing to do is to block in the views. As you block in the views, you are able to organize the sketch so it will clearly show the most information.
(1) A measurement should not be scaled from an aircraft print because the paper shrinks or stretches when the print is made. (2) When a detail drawing is made, it is carefully and accurately drawn to scale, and is dimensioned. Regarding the above statements,
*Both No. 1 and No. 2 are true. BothStatement (1) is true. Measurements should never be scaled from an aircraft drawing because the paper shrinks and stretches. The print is seldom the exact same size as the original drawing. Statement (2) is also true. When a detail drawing is made, it is carefully and accurately drawn to scale and is dimensioned.
(1) A detail drawing is a description of a single part. (2) An assembly drawing is a description of an object made up of two or more parts. Regarding the above statements,
*Both No. 1 and No. 2 are true. Statement (1) is true. A detail drawing is a description of a single part that includes enough information to allow the part to be manufactured (fabricated). Statement (2) is also true. An assembly drawing is a drawing that shows the way various detail parts are put together to form an assembly or a subassembly. Assembly drawings refer to the various parts to be assembled by the drawing number of their detail drawings.
The measurements showing the ideal or 'perfect' sizes of parts on drawings are called
*Dimensions. Allowances are the difference between the nominal dimension of a part and its upper or lower limit. Dimensions are the measurements used to describe the size of an object. It is the ideal or 'perfect' size of the part. Tolerances are the differences between the extreme allowable dimensions of a part.
What is used to indicate that a surface must be machine finished?
*Finished marks. By using finished marks a drawing identifies those surfaces that must be machine finished.
Sketches are usually made easier by the use of
*Graph paper. Sketches are easily made by using graph paper, which is available, ruled with light lines, in either four or five squares to the inch.
A line used to show an edge which is not visible is a
*Hidden line. A phantom line is a light line made up of an alternate long dash and two short dashes. A phantom line shows the location of a part that is used as a reference. A hidden line is a medium-weight, dashed line that shows a surface or a part that is not visible from the view in which it appears. A break line is a wavy or a zigzag line used to show that a part has been broken off and only part of it is shown.
In the reading of aircraft blueprints, the term 'tolerance,' used in association with aircraft parts or components,
*Is the difference between the extreme permissible dimensions that a part may have and still be acceptable. Tolerance is the difference between the extreme permissible dimensions of a part.
Zone numbers on aircraft blueprints are used to
*Locate parts, sections, and views on large drawings. Large drawings used for manufacturing aircraft are zoned to make it easy to locate parts, sections, and views on large drawings. Zone identifiers are placed every foot along the edge of the drawing. The identifiers along the bottom of the drawing are numbers and those up the side of the drawing are letters.
(1) Sketches are usually made with the aid of drafting instruments. (2) Sketches are usually more complicated to make when using graph paper. Regarding the above statements,
*Neither No. 1 nor No. 2 is true. Sketches are simple drawings made without the use of tools. It is easier to do a sketch on graph paper where dimensions are easier to visualize without using tools such as a ruler.
Which statement is true regarding an orthographic projection?
*One-view, two-view, and three-view drawings are the most common. An orthographic projection can show as many as six views of an object. One-view, two-view, and three-view drawings are the most commonly used types of orthographic projections.
(1) According to 14 CFR Part 91, repairs to an aircraft skin should have a detailed dimensional sketch included in the permanent records. (2) On occasion, a mechanic may need to make a simple sketch of a proposed repair to an aircraft, a new design, or a modification. Regarding the above statements,
*Only No. 2 is true. Statement (1) is not true. 14 CFR Part 91 requires that maintenance records contain 'a description (or reference to data acceptable to the Administrator) of the work performed...' There is no requirement in 14 CFR Part 91 that a detailed dimensional sketch of a repair become a part of the aircraft's permanent records. Statement (2) is true. A simple sketch is often needed to help a mechanic make a repair, a new design, or a modification.
(1) Schematic diagrams indicate the location of individual components in the aircraft. (2) Schematic diagrams indicate the location of components with respect to each other within the system. Regarding the above statements,
*Only No. 2 is true. Statement (1) is not true. Schematic diagrams do not indicate the location of individual components in the aircraft. Statement (2) is true. Schematic diagrams do show the location of the components with respect to each other within the system.
A specific measured distance from the datum or some other point identified by the manufacturer, to a point in or on the aircraft is called a
*Station number. A station number is a number used to identify the number of inches from the datum or other point identified by the manufacturer to a point in or on the aircraft.
What numbering system is used to locate fuselage frames?
*Station numbers. Locations for fuselage frames in aircraft drawings are identified by station numbers.
When reading a blueprint, a dimension is given as 4.387 inches +.005 -.002. Which statement is true?
*The minimum acceptable size is 4.385 inches. The part described here has a dimension of 4.387 inches, with a tolerance of +0.005, -0.002. The part could have a dimension of anywhere between 4.385 inches and 4.392 inches.
Which statement is applicable when using a sketch for making a part?
*The sketch must show all information to manufacture the part. A sketch is a simple, rough drawing made rapidly and without much detail. A sketch is frequently drawn for use in manufacturing a replacement part. Such a sketch must provide all necessary information to those persons who must manufacture the part.
Schematic diagrams are best suited for which of the following?
*Troubleshooting system malfunctions .A schematic diagram shows the relative location of all of the parts in a system, but does not give the location of the parts in the aircraft. Schematic drawings are of great help when troubleshooting a system.
What material symbol is frequently used in drawings to represent all metals?
*cast iron. If the exact specifications of a material are shown on the drawing, the easily drawn symbol for cast iron is used for the sectioning, and the material specification is listed in the bill of materials or indicated in a note.
What is the class of working drawing that is the description/depiction of a single part?
*detail drawing. A detail drawing is a description of a single part, given in such a manner as to describe by lines, notes, and symbols the specifications as to size, shape, material, and method of manufacture that are to be used in making the part.
Working drawings may be divided into three classes. They are:
*detail drawings, assembly drawings, and installation drawings. The three classes of working drawings are: detail drawings, assembly drawings, and installation drawings.
A hydraulic system schematic drawing typically indicates the
*direction of fluid flow through the system. A schematic drawing of a hydraulic system would not show the specific location of any of the parts in the aircraft, nor the amount of pressure in the pressure and return lines, and in system components. A schematic drawing shows the way all of the components are connected together to form the complete system. It also shows the direction the fluid flows through the system.
A simple way to find the center of a circle on a sketch or drawing, or a circular piece of material is to
*draw two non-parallel chord lines across the circle and then a corresponding perpendicular bisector lines across each chord line. An easy way to find the center of a circle on a sketch is to draw two non-parallel chord lines across the circle. Then, draw a perpendicular bisector of each of these chord lines. The bisector lines will cross at the center of the circle.
The drawings often used in illustrated parts manuals are
*exploded-view drawings. The drawings used in illustrated parts manuals are exploded-view drawings.
One purpose for schematic diagrams is to show the
*functional location of components within a system. Schematic diagrams are used to show the functional location of components within the system by showing all of the components laid out in the way that they relate to each other in the functioning of the system. Schematic diagrams do not show the physical location of the components within a system, nor do they show the size and shape of the components.
For sketching purposes, almost all objects are composed of one or some combination of six basic shapes; these include the
*triangle, circle, cube, cylinder, cone, and sphere. Almost all objects are composed of one or some combination of the triangle, circle, cube, cylinder, cone, and sphere.
