Figure 3-7.Pictorial drawing with expioded view
Block diagrams may be used to illustrate a system.
The nosewheel steering system in figure 3-6 is a good
example of the use of a block diagram.
In the block diagram, each of the components of
the system is represented by a block. The name of the
component represented by each block is near that
block. Block diagrams are also useful in showing the
relationship of the components. They also may show
the sequence in which the different components
A pictorial drawing is a representation of both the
detail and the entire assembly. Figure 3-7 is an example
of a pictorial drawing. Another use of this type of
drawing is to show disassembly, or an exploded view.
This type of drawing enables the mechanic to see how
the parts of a particular piece of equipment are put
Orthographic drawings are used to show details of
parts, components, and other objects, and are primarily
used by the manufacturer of the object. Usually, two or
more views of the object are given on the drawing.
Detailed instructions on reading orthographic, as well
as all other types of drawings, are contained in Blueprint
Reading and Sketching NAVEDTRA 10077-F1.
One of the more important factors in trouble-
shooting a system logically is your understanding of the
components and how they operate. You should study the
information and associated schematics provided in the
MIM. The function of each component and possible
malfunctions can be used in the process of analyzing
actual malfunction symptoms.
A primary concern in troubleshooting an aircraft
hydraulic system is to determine whether the mal-
function is caused by hydraulic, electrical, or mechan-
ical failure. Actuating systems are dependent on the
power systems. Some of the troubles exhibited by an
actuating system may be caused by difficulties in the
power system. A symptom indicated by a component of
the power system may be caused by leakage or
malfunction of one of the actuating systems. When any
part of the hydraulic system becomes inoperative, use
the diagrams in conjunction with the checkout
procedures provided in the aircraft MIM. Possible
causes of trouble should always be eliminated
systematically until the pertinent cause is found. No
component should be removed or adjusted unless there
is a sound reason to believe the unit is faulty.