subject B - Aircraft Drawing

What types of lines are used on mechanical drawings to show alternate position? Hidden views? Center lines?

Phantom lines show alternate positions: one long and two short dashes. Hidden lines are short dashes evenly spaced. Center lines are alternate long and short dashes.

How are dimensions lines shown on aircraft drawings?

Dimension lines are solid, and usually broken at midpoint for insertion of measurement indications.l——————27”—————-l.

What is a sketch for a repair?

It is a basic drawing that shows specific information and provides minimum detail to manufacture a part.

How may an aircraft drawing of a part be drawn to bring out pertinent details?

By drawing a detailed view at a larger scale than the principal view.

What are schematic diagrams generally used for?

They are mainly used for troubleshooting.

Define “tolerance” as used in aircraft drawings.

The difference between the plus and minus allowable dimension of a part.

Define “clearance” as used in aircraft drawings?

Clearance is a dimension allowable between two parts.

What is a fuselage station number?

It is the distance from the datum measured in inches along the longitudinal axis.

What information is given in the title block for f a blueprint?

The drawing number, the name of the part or assembly, the scale, the date, the name of the firm, the name of the draftsman, the checker, and the approving official.

Where is the tile block usually found on an aircraft drawing?

In the lower right corner.

Why are dimension used, and how are they shown on the aircraft drawing?

Dimension are narrow solid lines, broken at midpoint for the insertion of measurements. They are used to indicate the size of an object.

How can a change to an aircraft drawing be identified?

By its revision letter (A,B,C, etc…). The revision letters are usually listed in a table next to the title block or in the corner of the drawing.

What is the “bill of materials” associated with aircraft blueprint?

It is a list of materials and parts necessary for fabrication or assembly of component or system.

Why are symbols used when drawing aircraft blueprints?

Symbols are type of shorthand used in drawings. They express the characteristics of a component with a minimum amount of drawing.

What is a orthographic projection?

A way of clarification an object in drawing, by showing different views at right angles to each other, such as front and side view.

How many views are required to determine the shape of an object?

One-, two-, and three-view drawings are most commonly used.

What is the purpose of one view drawing?

They are used for objects of uniform thickness, which as gaskets, shims, and plates.

Describe the purpose and use of zone numbers in aircraft drawings.

Zone numbers on drawings are like the numbers and letters printed on the borders of a map. They help locate a point, mentally draw horizontal and vertical lines from the letters and numeral specified; the point where these lines intersect is the area sought.

What is the name of a part of drawing used to bring out important details and how is it drawn?

A detailed view, which is usually drawn to a large scale than the main drawing.

What is allowance?

Is the difference between the nominal dimension and the maximum and minimum permissible sizes.