by subject to aid in identifying active naval instructions.
The index is divided into four sections:
Alphabetical listinglists instructions by subject
Numerical listinglists instructions first by
sponsor, then in numerical sequence
Recently canceled and/or superseded instruc-
tionslists all instructions recently canceled by
Navy implementation of Department of Defense
(DOD) issuancesprovides a cross-reference
listing to assist activities requesting DOD
MAINTAINING TECHNICAL MANUALS
Maintaining your technical manuals so they are
up-to-date is as important as maintaining any other
valuable tool. Your technical manuals must reflect the
actual equipment configurations that you have at your
command. An out-of-date manual or a manual that does
not reflect any changes that may have been made to your
equipment may prove to be useless when you try to
Changes or update information you receive to
NAVSEA technical manuals will be in one of three
forms: 1) Advance Change Notice (ACN), 2) Permanent
Change, or 3) Revision. After receiving any change or
update to a tech manual, you should first ensure that the
Field Change, ORDALT, SHIPALT and so forth, is
installed in your equipment. If you indicate a change in
a manual that is not made in the equipment, the manual
will be incorrect. Making an incorrect change to a
technical manual is as bad as not making a change when
one is required.
Advance Change Notice (ACN)
An ACN is issued when there is an urgent need to
add, correct, or expand information in a technical
manual to prevent injury or death to personnel or
damage to equipment. The ACN is issued by the
responsible NAVSEA technical activity in response to a
known need for immediate corrective action.
An ACN may be issued as a naval message, a letter,
a NAVGRAM, or in an Engineering Information
When you receive an ACN, you should do the
1. Determine whether or not the ACN applies to
your technical manual.
2. If it does apply, enter the changes into your
3. Record the entry on the Record of Changes page.
Permanent changes are issued to add system or
equipment configuration variations and new procedures
and to change existing procedures. They are also used
to highlight outstanding ACNs and to correct other
Most permanent changes to technical manuals are
identified by a vertical line, known as a change bar,
extending along the margin of the changed material.
When changes to an entire part, chapter, or section are
made, a change bar will not be present.
When you receive a Permanent Change, you should
take the following steps:
Determine whether or not the change applies to
the technical manual for your system/equipment
Check the Permanent Change Package against
the Change Instruction Sheet and the List of
Effective Pages to be sure you have a complete
set of change pages.
Add replacement pages and new pages, and
remove replaced pages according to the
instructions that come with the change package.
Record the entry on the Record of Changes page.
Destroy the removed pages according to your
local disposal instructions.
Insert the Change Instruction Sheet immediately
following the title page.
A revision is a second or later edition of a technical
manual. A revision is issued whenever it is necessary to
change the majority of pages in an existing manual. A
revision may be required because of hardware
modification, because of a deficiency that affects a large
part of the manual, or because a change of system
configuration results in one volume or part of a
multivolume or multipart set being revised.
When you receive a technical manual revision, you
1. Verify that the revised manual applies to your
ship, system, or equipment configuration.