Figure 13-22.—Modern submarine.
on the hull, and bow profile. The visual coding
approach is based on examining the profile
appearance of a given submarine and assigning
numerical values that best correspond with illustrated
examples appearing in selected appearance group
coding. Three factors are usually sufficient to identify
a class; thus each submarine class has a three-digit
number. In cases where several submarines possess
the same appearance code number, their profile and
photographs should be carefully compared to
distinguish between them.
General Appearance Coding
Surface submarines and partially submerged
submarines are best identified by their sail
configuration; hence, the sail shape is the most
important factor in coding the general appearance of
submarines. (See fig. 13-23.)
Sail Placement Coding
The system for coding the sail placement parallels
and reinforces the system outlined under General
Appearance Coding. Generally, the sails of newer
submarines are placed closer to the bow than those of
older designs. In examining the five basic sail
positions (fig. 13-24), you should choose the example
that best shows the position of the sighted sail in
relation to the hull. Using this system, you should be
within two or three silhouettes in confirmation of
submarine class and type.
Bow Profile Coding
Bow profiles (fig. 13-25) are assigned numerical
values in an ascending order that coincides with the
severity of the angle at which the stem or deck line
approaches the waterline. On the newer submarines,
the bulbous bow is seldom seen; when the submarine
is surfaced, the deck line forward of the sail appears
to slope gently into the water. On the older submarines
the bow has a definite terminal point, and the angle of
the stem is either raked or sheer. Note that in the
coding of bow profiles, structures atop the bow are not
considered as part of the bow shape. Bow shapes are
often difficult to see because of observation angle or
water wave action; but this should not constrain you
from identifying a particular submarine based on the
first two codes.
General Recognition Factors
The principal Soviet innovation is the streamlined
turtleback sail, which has a curved topline that merges
with the after trailing edge of the sail. For
classification, the new turtleback sail is assigned
appearance group code 1. (See fig. 13-23.)
Rectangular sails are so numerous that they must
be broken down into subdivisions as to how they
appear in relation to other features. The new SSBNs
usually have a rectangular sail with sail planes. They
also have a bullet-shape bow, a stern fin, and a
prominently raised and broken deck line aft of the sail.
The SSBN classes largely constitute appearance group
2 (fig. 13-25).
13-16
