JOINT FLEET MAINTENANCE MANUAL

COMFLTFORCOMINST 4790.3 REV A
(2) Arrangement drawings - Arrangement drawings show locations, dimensions, and other system
component information necessary to make correct installation on the ship.
(3) Assembly and subassembly drawings - Assembly and subassembly drawings show how
individual parts fit together to form a larger component or equipment.
(4) Installation drawings - Installation drawings show piping, foundations, ventilation ducting, and
other installation details. Installation drawings are used to install systems and equipment in the
ship.
(5) Outline drawings - Outline drawings show the outward appearance of major system
components and contain dimensions and service requirements necessary to install the
component.
(6) Detail drawings - Detail drawings show dimensions and other manufacturing data for
individual parts of components.
(7) Electrical drawings - Electrical drawings have a family of titles similar to those of other
engineering drawings. Proceeding from the general to the detailed the following are the
common electrical drawing types:
(a) Electrical system wiring diagrams - Electrical system wiring diagrams show how the
overall system is intended to function.
(b) Cabling drawings - Cabling drawings describe cable runs in greater detail (similar to
piping system diagrams).
(c) Wireway drawings - Wireway drawings show how cables are routed from one point to
another in the ship (similar to system arrangement drawings).
(d) Schematic wiring diagrams - Schematic wiring diagrams describe individual wires
inside the cables and how they connect to components.
(e) Wiring tables - Wiring tables provide detailed point-to-point data for connecting ship's
wiring between components.
d. Technical Variance Documentation (TVD). Drawings may be amended with supplementary
information called TVD. A set of TVD is a collection of documents describing how the as-built
configuration of a ship differs from the class drawing design. TVD is not intended to be a revision to a
drawing. Liaison Problem and Solution Sheets, Engineering Notices, Waivers and Deviations are some
of the documents that make up TVD.
e. Format of Onboard Drawings. Very few drawings are provided to ships and shore facilities in hard
copy form. Most are on microfilm aperture cards or microfiche, collectively known as microform. For
selected platforms, Compact Disc Read Only Memory (CD-ROM) is being utilized. However, some of
the more important SRDs are provided in hard copy as well as in other mediums.
I-3-14