to discrete components and, in some cases, to a set of
several digital cards. You’ll complete most repairs by
removing and replacing discrete chassis components,
modules, or digital circuit cards.
The Air Force performs depot-level maintenance on
DAIR equipment under a joint maintenance task
agreement; however, the contractor will repair all
CATCC- and AATC DAIR-unique items at the depot
level. Return the items that you can’t repair to supply.
They’ll know where to send them.
All the systems we’ve discussed so far are the
maintenance responsibility of the ET rating. The next
system, NTDS, is maintained by several ratings. As we
explained in ET, Volume 3, Communications Systems,
the only way to ensure optimum operation of the NTDS
system is to work closely with the other ratings involved.
NAVAL TACTICAL DATA SYSTEM
(NTDS)
ET, Volume 3, addresses the NTDS tactical
communications data system. In this volume, we will
address the tactical radar section.
The NTDS
computer-centered control system coordinates the
collection of data from various sources. It accepts data
from ship’s sensors, such as radar, sonar, and navigation
inputs, and from external (off-ship) sources via
communications links. It also processes and correlates
this data for tactical use.
GENERAL THEORY OF OPERATION
NTDS accomplishes its objectives in real time; the
system receives data from various sensing devices that
are in continuous contact with the outside environment.
It uses this data to evaluate an event as it happens. How
often the system requires an update will determine the
rate of sampling for each sensing device. The concept
of standard computers operating in conjunction with
each other to increase capacity and functional capability
is known as the “unit computer concept.” It is basic to
the design philosophy of NTDS. A diagram of a typical
NTDS equipment grouping is shown in figure 3-8.
NTDS integrates all systems and subsystems for
performing the basic combat system functions
including:
Detection and entry
Tracking and identification
Threat evaluation and weapon assignment
Engagement and engagement assessment
The NTDS system accomplishes its varied tasks by
receiving, storing, and processing the data inputs from
the other systems and subsystems. The operational
program then distributes the processed data as usable
inputs for other systems and subsystems. The data
display also allows the operator to interact with the
system.
Figure 3-8.—NTDS equipment grouping.
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