Specs to go out 3.pdf

NAVSSI-B423-IRS

FOUO 4 May 2011

INTERFACE REQUIREMENTS SPECIFICATION (IRS)

FOR THE

OUTPUT DATA (OD) MESSAGES

OF THE

NAVIGATION SENSOR SYSTEM INTERFACE (NAVSSI)

AN/SSN-6(V)

BLOCK 4.2.3

Prepared by SPAWAR Systems Center, Pacific

Code 5237

Distribution D:

Distribution authorized to the Department of Defense and U.S. DoD contractors only; Critical Technology and Direct Military Support; 2008. Other requests shall be referred to Commanding Officer, SPAWAR Systems Center - Pacific, PNT Systems Development, code 5237, San Diego, California 92152-5001.

Warning:

This document contains technical data whose export is restricted by the Arms Export Control Act (Title 22, U.S.C, SEC 2751, ET SEQ) or the Export Administration Act of 1979, as amended (Title 50, U.S.C., APP 2401, ET SEQ).

Violation of these export laws is subject to severe criminal penalties. Disseminate in accordance with DoD Directive

5230.25 (Series).

Destruction Notice:

Destroy by any method that will prevent disclosure of contents or reconstruction of the document.

Page ii Distribution D

This page intentionally left blank.

Distribution D Page iii

Page iv Distribution D

Distribution D Page v

TABLE OF CONTENTS

1 SCOPE

1.1 IDENTIFICATION

1.2 SYSTEM OVERVIEW

1.3 DOCUMENT OVERVIEW

2 REFERENCED DOCUMENTS

2.1 GOVERNMENT DOCUMENTS

3 REQUIREMENTS

3.1 INTERFACE IDENTIFICATION

3.2 DATA REFERENCING

3.3 MESSAGE FORMAT

3.4 DATA ELEMENTS DEFINITIONS

3.5 DATA ELEMENTS CHARACTERISTICS

3.6 STATUS ELEMENTS

3.6.1 NAVSSI Status Element

3.6.1.1 Usage of Originating RTS and Originating RTS (Alt) Fields

3.6.2 NAV Status 1 Field Descriptions

3.6.3 NAV Status 2 Field Descriptions

3.6.4 NAV Status 2 (CMD) Field Descriptions

3.6.5 GPS Status V6 Element

3.6.6 GPS Status (CMD) Element

3.6.7 GPS Status V7 Element

3.6.8 Antenna (CMD) Status Element

3.6.9 Antenna V7 Status Element

3.6.10 FOAL Status Element

3.6.11 INS Status V6 (OD17) Element

3.6.12 INS Status V6 (OD19) Element

3.6.13 INS Status V7 Field Descriptions

3.6.14 OSD Status Field Descriptions

3.6.15 MV Status Field Descriptions

3.6.16 True Wind Status Field Descriptions

3.6.17 Relative Wind Status Field Descriptions

3.7 OUTPUT DATA MESSAGES

3.7.1 BFTT Training Message (OD12)

3.7.2 NAVSSI Navigation Sensors Message (OD17)

3.7.3 NAVSSI Navigation Message (OD19)

3.7.4 Common Navigation Message (OD22)

3.7.5 NAVSSI Extended Sensors Messages (OD37)

3.7.6 NAVSSI Heart Beat Message (OD38)

3.7.7 NAVSSI Extended Navigation Message (OD39)

3.8 SAMPLE MESSAGE FORMAT

4 QUALIFICATION PROVISION

5 ACRONYMS AND ABBREVIATIONS

Page vi Distribution D

LIST OF TABLES

TABLE 3-1 DATA ELEMENTS CHARACTERISTICS

TABLE 3-2 NAVSSI STATUS

TABLE 3-3 THE ORIGINATING RTS AND ORIGINATING RTS (ALT) FIELDS

TABLE 3-4 NAV STATUS 1 WORD

TABLE 3-5 NAV STATUS 2 WORD

TABLE 3-6 NAV STATUS 2 (CMD) WORD

TABLE 3-7 GPS STATUS V6

TABLE 3-8 GPS STATUS (CMD)

TABLE 3-9 GPS STATUS V7

TABLE 3-10 ANTENNA (CMD) STATUS

TABLE 3-11 ANTENNA V7 STATUS

TABLE 3-12 FOAL STATUS

TABLE 3-13 INS STATUS V6 (OD17)

TABLE 3-14 INS STATUS V6 (OD19)

TABLE 3-15 INS STATUS V7 WORD

TABLE 3-16 OSD STATUS

TABLE 3-17 MV STATUS

TABLE 3-18 TRUE WIND STATUS

TABLE 3-19 RELATIVE WIND STATUS

Distribution D Page vii

LIST OF FIGURES

FIGURE 3-1 TYPICAL MESSAGE FORMAT

FIGURE 3-2 BFTT TRAINING MESSAGE FORMAT

FIGURE 3-3 NAVIGATION SENSORS MESSAGE FORMAT

FIGURE 3-4 NAVSSI NAVIGATION MESSAGE FORMAT

FIGURE 3-5 COMMON NAVIGATION MESSAGE FORMAT

FIGURE 3-6 NAVIGATION EXTENDED SENSORS MESSAGE FORMAT

FIGURE 3-7 NAVSSI HEART BEAT MESSAGE FORMAT

FIGURE 3-8 NAVSSI EXTENDED NAVIGATION MESSAGE FORMAT

FIGURE 3-9 SAMPLE OPERATIONAL MESSAGE FORMAT

Page viii Distribution D

Distribution D Page 1

1 SCOPE

1.1 Identification

This Interface Requirements Specification (IRS) defines the contents and format of a standard set of Output Data (OD) messages that are distributed by the Navigation Sensor System Interface (NAVSSI). These OD messages contain navigation data and they are sent over a variety of physical interfaces, both point-to-point and networked, to a variety of users. This IRS supports all releases of NAVSSI Block 4.2.3.

1.2 System Overview

NAVSSI is a system designed to integrate the inputs from various navigation sensors and provide the integrated navigation solution, precise time, and frequency data to shipboard weapon, combat support, command and control, communication, training, and navigation systems.

The NAVSSI Block 4.2.3 is a followed-on to Block 4.2.1 and incorporates the End Of Life (EOL) replacements. It adds support for an embedded Selective Availability Anti-Spoofing Module (SAASM) GPS receiver and resolves hardware component obsolescence issues, among these are PowerPC Processor card, Input/Output (I/O) serial card and network interface cards. In addition, DCS rack is eliminated and the user interface functionality becomes a part of the NCS, which is embedded in the RTS rack. The RTS integrates data from both an embedded GPS SAASM receiver and external navigation sensors and provides in real-time, precise Positioning Navigation and Timing (PNT) data to shipboard users. The RTS is a mission critical capability that can operate without the NCS. The NCS provides the capability to control and display the ship’s navigation sensor information and log data to non-volatile storage. The remote NCS extends the NAVSSI control and display capabilities to the ship’s crew in other shipboard locations. The NAVSSI Subsystems (RTS, NCS, and remote NCS) communicate via a dedicated inter-subsystem

LAN.

1.3 Document Overview

The information contained in this document is unclassified. This IRS is prepared in accordance with MIL-STD-498 using the Data Item Description guidelines set in DI-IPSC-81434.

Page 2 Distribution D

2 REFERENCED DOCUMENTS

2.1 Government Documents

The following documents form a part of this specification to the extent specified herein. In the event of a conflict between the documents referenced herein and the contents of this specification, the contents of this specification shall be considered a superseding specification.

Specifications and Standards:

DI-IPSC-81434 Data Item Description for Interface Requirements Specifications

NAVSSI-B423-SSS System/Subsystem Specification for the Navigation Sensor System Interface (NAVSSI) AN/SSN-6(V) Block 4.2.3. 13 September 2010

NAVSSI-B423-SMF&P Standard Message Format and Protocol, Rev 7.3, 4 May 2011

NAVSSI-B4.3-CMD-NAVDDX Common Message Data (CMD) for the Navigation Data Distribution Extension (NAVDDX), 20 December 2008.

T8901-XX-IRS/IDD/BFTT Interface Requirements Specification/Interface Design Document (IRS/IDD) for BFTT NAVSIM & NAVSSI 100BaseFX, Appendix O-4, 23 December 2005

DOD-STD-498 Software Development and Documentation. 5 Dec 1994

IC 809632/000 GPS Advanced Digital Antenna Production (ADAP) Antenna Electronics (AE) [As 4616/A] Interface Control Document (Interface Specification) Issue 5 19 Jul 2006

IC 808352/000 GPS User Equipment GAS-1 Interface Control Document AS-4564/SRN, 4555/AR, 3281A/ARN Issue 7c Nov 2006

ICD-GEM-155 Interface Control Document GPS Embedded Module 155, Rev B, 04 Mar

ICD-GPS-156 GPS User Equipment, Interface Control Document for GPS VME Receiver Card (GVRC), Rev 3, 22 May 2001

Distribution D Page 3

3 REQUIREMENTS

3.1 Interface Identification

This IRS describes the content and format of the OD messages, but it does not address the physical interface to be used to enact the specific NAVSSI interface, which delivers the NAVSSI OD Messages. Such detail will be found in the appropriate Interface Design Description (IDD).

Messages generated in accordance with this IRS are of two major revisions. Version 7 messages and data elements are new, and follow the version 7 enumerations and headers as specified in the SMF&P version 7 document (NAVSSI-B423-SMF&P) listed in section 2. Version 6 messages and data elements are provided for backwards compatibility, and follow the previous versions of the SMF&P exclusively. NAVSSI-B423-SMF&P does provide in addition to version 7 enumerations and header descriptions, all version 6 enumerations and header descriptions.

Elements that have more than one revision are identified with V6 and V7 as part of the element name. A third variant (CMD) follows another enumeration document (NAVSSI-B4.3-CMD-NAVDDX) and applies only to elements of OD22.

All messages will be sent in Big Endian format. Big Endian is an order in which the "big end" (most significant value in the sequence) is stored and transmitted first (at the lowest storage address).

3.2 Data Referencing

NAVSSI outputs of Position and Velocity will normally be referenced to a single point on each ship designated as the OSRP. The Platform Manager for the specific Ship Class will designate this point and its location will vary by ship class. In order to provide position and velocity relative to OSRP, NAVSSI performs the requisite translations on all navigation sensor input data.

NAVSSI treats the ship as a rigid body and that Attitude, Attitude Rate, and Attitude Acceleration are the same at all points on the ship. As such, these quantities are already accurate at OSRP and no translations are required.

Page 4 Distribution D

3.3 Message Format

The Output Data (OD) messages consist of three distinct parts:

Message Header Payload Section Checksum

The message header contains information that helps in parsing the message and the payload. It also provides some indications that pertain to the entire message and also source of the message.

The payload section contains all the message data. Data is provided as data elements and data headers.

Checksum provides a mechanism to validate the message integrity.

The message format is depicted in Figure 3-1.

Figure 3-1 Typical Message Format

The message header, data header and checksum are all defined in the SMF&P document referenced in section 2.

An example of how to construct a message is provided in section 3.8.

Distribution D Page 5

3.4 Data Elements Definitions

Acceleration Down: Down component of own ship’s acceleration along the direction of the reference ellipsoid vertical. Positive is defined as down.

Acceleration East: East/west component of own ship’s linear acceleration. Positive is defined as East.

Acceleration North: North/south component of own ship’s linear acceleration. Positive is defined as North.

Attitude, Fox Corpen: Ship’s course to steer in order to get the correct wind speed and direction to land aircrafts.

Attitude, Heading: Angle between the geographic North-South vertical plane and the vertical plane through the ship’s centerline, measured in the horizontal plane. Angles are measured clockwise from North.

Attitude, Heading, BFTT: Heading as provided in the BFTT message received by NAVSSI.

Attitude, Heading, INS1: Heading as provided by INS1.

Attitude, Heading, INS2: Heading as provided by INS2.

Attitude, Heading Acceleration: Rate at which own ship’s heading rate changes.

Attitude, Heading Magnetic North : Heading in reference to the magnetic north. Magnetic north is the direction to which a magnetic compass points to and by doing so indicates the direction of earth’s magnetic pole.

Attitude, Heading Magnetic True: Measured magnetic heading corrected with the local variation.

Attitude, Heading Rate: Rate at which own ship’s heading changes. Positive values indicate ship is turning starboard side.

Attitude, Heading Rate, BFTT: Heading rate as provided in the BFTT message received by NAVSSI.

Attitude, Heading RMS Error: Estimated RMS angular error about the heading axis.

Attitude, Heave: Vertical displacement of the ship.

Attitude, Pitch: Angle between the horizontal plane and the deck plane measured in the vertical plane through the ship’s centerline. Positive angles are measured downward from the horizontal plane (bow down is positive).

Attitude, Pitch Acceleration: Rate at which own ship’s pitch rate changes.

Attitude, Pitch Rate: Rate at which own ship’s pitch changes.

Attitude, Pitch RMS Error: Estimated RMS angular error about the pitch axis.

Attitude, Roll: Angle between the vertical plane through own ship centerline and the normal plane (through the intersection of the vertical plane through own ship centerline and the deck plane), measured about the axis, which is the intersection of the vertical plane through own ship centerline and the deck plane. Positive angles are measured clockwise when viewed from own ship bow (starboard up).

Attitude, Roll Acceleration: Rate at which own ship’s roll rate changes.

Attitude, Roll Rate: Rate at which own ship’s roll changes.

Page 6 Distribution D

Attitude, Roll RMS Error: Estimated RMS angular error about the roll axis.

Course: Track of own ship over the ground. Positive angles are measured clockwise from the North.

Course, BFTT: Course as provided in the BFTT message received by NAVSSI.

Current, Drift: Ocean current speed.

Current, Ocean East: East/west component of ocean current.

Current, Ocean East, BFTT: Ocean current east as provided in the BFTT message received by NAVSSI.

Current, Ocean North: North/south component of ocean current.

Current, Ocean North, BFTT: Ocean current north as provided in the BFTT message received by NAVSSI.

Current, Set: Direction of motion of the ocean current.

Depth Below Keel: Measured depth of water below the keel.

Depth Below Keel, BFTT: Depth below the keel as provided in the BFTT message received by NAVSSI.

GPS, C/No: Carrier to Noise ratio of the specified channel.1

GPS1, C/No: Carrier to Noise ratio of the specified channel as provided by the GPS receiver in RTS1.

GPS2, C/No: Carrier to Noise ratio of the specified channel as provided by the GPS receiver in RTS2.

GPS, Elevation Mask Angle: Horizon elevation limiting satellite tracking.

GPS, Hardware Channel: GPS receiver hardware channel used. 1

GPS1, Hardware Channel: GPS receiver hardware channel used as indicated by the GPS receiver in RTS1.

GPS2, Hardware Channel: GPS receiver hardware channel used as indicated by the GPS receiver in RTS2.

GPS, J/S: Jammer to signal ratio related to the specified channel.1

GPS1, J/S: Jammer to signal ratio related to the specified channel provided by the GPS receiver in RTS1.

GPS2, J/S: Jammer to signal ratio related to the specified channel provided by the GPS receiver in RTS2.

GPS, Satellite Number: The number of the GPS satellite.1

GPS1, Satellite Number: The number of the GPS satellite provided by the GPS receiver in RTS1.

GPS2, Satellite Number: The number of the GPS satellite provided by the GPS receiver in RTS2..

Integral of Velocity East: Cumulative integral of filtered own ship’s Velocity East.

Integral of Velocity North: Cumulative integral of filtered own ship’s Velocity North.

1 The combination word that contains “GPS Satellite Number”, “GPS Hardware Channel”, “GPS C/No” and “GPS J/S” uses data obtained from one of the GPS’s receiver top five logical channels. Data from all five logical channels is provided in OD39, while in OD37 only one is provided – the one with the highest J/S.

Distribution D Page 7

Magnetic Variation (MV): Horizontal angle between the true north and magnetic north measured east or west depending if magnetic north lies east or west of true north. Positive value = East.

Meteorological, Dew Point: Temperature at which water vapor condenses into water.

Meteorological, Humidity, Relative: The amount of water vapor in the air.

Meteorological, Pressure, Barometric: A measure of air pressure that correlates with weather and altitude. It is the amount of downward force exerted by the weight of the air above and is measured in inches of mercury (Hg).

Meteorological, Temperature, Air: Ambient air temperature as measured by a suitable instrument.

Meteorological, Temperature, Water: Water Temperature at the sensor.

Own Ship Distance (OSD): A measure indicating the distance the ship traveled since the last time this field was reset.

Position, East RMS Error: Estimated RMS position error along the east axis.

Position, ECEF, X: Position utilizing the WGS-84 ECEF Coordinates (Center of Earth, X axis).

Position, ECEF, Y: Position utilizing the WGS-84 ECEF Coordinates (Center of Earth, Y axis).

Position, ECEF, Z: Position utilizing the WGS-84 ECEF Coordinates (Center of Earth, Z axis).

Position, GPS Altitude (Absolute): Vertical position referenced to WGS-84 reference ellipsoid.

Position, GPS Altitude (MSL): Vertical position referenced to mean sea level.

Position, Latitude: Angle between the local geodetic vertical and the equatorial plane measured in the local meridian vertical plane given in WGS-84 coordinates. Positive latitude is measured northward from the equatorial plane. The accuracy of Latitude is expressed in the North RMS error.

Position, Latitude BFTT: Latitude as provided in the BFTT message received by NAVSSI.

Position, Latitude GPS1: Latitude as provided by GPS1.

Position, Latitude GPS2: Latitude as provided by GPS2.

Position, Latitude INS1: Latitude as provided by INS1.

Position, Latitude INS2: Latitude as provided by INS2.

Position, Longitude: Angle between the Greenwich Meridian vertical plane and the local meridian vertical plane measured in the local equatorial plane given in WGS-84 coordinates. Positive longitude is measured eastward from the Greenwich Meridian. The accuracy of Longitude is expressed in the East RMS errors.

Position, Longitude BFTT: Longitude as provided in the BFTT message received by NAVSSI.

Position, Longitude GPS1: Longitude as provided by GPS1.

Position, Longitude GPS2: Longitude as provided by GPS2.

Position, Longitude INS1: Longitude as provided by INS1.

Page 8 Distribution D

Position, Longitude INS2: Longitude as provided by INS2.

Position, North RMS Error: Estimated RMS position error along the north axis. RMS error includes both the bias and variance portions of the error.

Position, Radial Error Estimate: Estimated radial error of the NAVSSI position solution.

Position, Vertical: Vertical position with respect to the WGS-84 reference ellipsoid. Positive is defined as down.

Unless otherwise specified in the NAVSSI Status word, the Vertical Position is for OSRP. The accuracy of Vertical Position is expressed in the Vertical Position RMS error.

Position, Vertical BFTT: Vertical position as provided in the BFTT message received by NAVSSI.

Position, Vertical GPS1: Vertical position as provided by GPS1.

Position, Vertical GPS2: Vertical position as provided by GPS2.

Position, Vertical INS1: Vertical position as provided by INS1.

Position, Vertical INS2: Vertical position as provided by INS2.

Position, Vertical RMS Error: Estimated RMS position error along the vertical axis.

Speed, Athwartships: Own ship’s port/starboard speed with respect to the bottom or surrounding water, depending upon the operational mode of the ship’s speed sensor. Starboard is positive.

Speed, Athwartships, BFTT: Own ship’s port/starboard speed as provided in the BFTT message received by

NAVSSI.

Speed, Best: The available top rank speed selection source of the RTS. Field will contain STW unless STW is either invalid or unavailable at which point, the field will have SOG.

Speed Log, Calibration: Calibration correction being applied to the fore/aft speed log data by the INS currently being used by NAVSSI.

Speed Over Ground (SOG): Ground speed calculated from North Velocity and East Velocity.

Speed Through the Water, BFTT: STW as provided in the BFTT message received by NAVSSI.

Speed Through the Water, V6 (STW or SOG): The available top rank speed selection source of the RTS. Field will contain STW unless STW is either invalid or unavailable at which point, the field will have SOG.

Speed Through the Water, V7 (STW): Fore/Aft speed of the ship’s hull relative to the water as provided by the ship’s speed sensor. Also called own ship speed.

Speed, Vertical: Own ship’s up/down speed with respect to the bottom or surrounding water, depending upon the operational mode of the ship’s speed sensor. Down is positive.

Speed, Vertical, BFTT: Vertical speed as provided in the BFTT message received by NAVSSI.

Distribution D Page 9

Status, Antenna (CMD): Status information related to the GPS antenna used as provided in OD22, See Section

3.6.8 for details. 2

Status, Antenna1 V7: Status information related to the GPS antenna used by the GPS receiver in RTS1. See Section

3.6.9 for details. 2

Status, Antenna2 V7: Status information related to the GPS antenna used by the GPS receiver in RTS2. See Section

3.6.9 for details. 2

Status, FOAL 1: Status information related to the FOAL receiver drawer in RTS1. See Section 3.6.10 for details.

Status, FOAL 2: Status information related to the FOAL receiver drawer in RTS2. See Section 3.6.10 for details.

Status, FOAL, Remote: Status information related to the remote FOAL receiver drawer. See Section 3.6.10 for details.

Status, GPS: Status information related to the ship’s primary GPS receiver, see Section 3.6 for details. Data header source will indicate GPS1, GPS2, or GPS3 as source. If blended, data header source will be the same as message header source.

Status, GPS 1: Status information related to the GPS receiver in RTS1. See Section 3.6.5 for details .

Status, GPS 2: Status information related to the GPS receiver in RTS2. See Section 3.6.5 for details.

Status, GPS (CMD): GPS status information as provided in OD22. See Section 3.6.6 for details.

Status, GPS V6: GPS receiver status information as provided in OD17 and OD19. See Section 3.6.5 for details.

Status, GPS V7: GPS status information as provided in OD37 and OD39. See Section 3.6.7 for details.

Status, INS: Status information related to the ship’s INSs. See Section 3.6 for details. Data header source will indicate INS1, INS2, or INS3. If blended, data header source will be the same as message header source

Status, INS V6 (OD17): Status information as provided in OD17. See Section 3.6.11 for details.

Status, INS V6 (OD19): Status information as provided in OD19. See Section 3.6.12 for details.

Status, INS V7: Status information as provided in OD22, OD37 and OD39. See Section 3.6.13 for details.

Status, Magnetic Variation (MV): Indicates if the magnetic variation data in this message is considered valid. See Section 3.6.15 for details.

Status, NAVSSI: Status information related to NAVSSI as provided by OD17 and OD19, See Section 3.6.1 for details.

Status, NAV1: Status information related to NAVSSI as provided by OD22, OD37 and OD39, see 3.6.2 for details.

Status, NAV2: Status information related to NAVSSI as provided by OD37 and OD39, see 3.6.3 for details.

Status, NAV2 (CMD): Status information related to NAVSSI as provided by OD22, see 3.6.4 for details.

2 Antenna 1 is the antenna that is connected to RTS 1 and is considered “Main” antenna on the FOAL drawer, or “A” antenna on FOAL drawer V2. Antenna 1 is the forward or starboard mounted antenna. Data header source will indicate which antenna is the source.

Page 10 Distribution D

Status, OSD: Indicates if own ship distance data for each speed source is considered valid. See Section 3.6.14 for details.

Status, Relative Wind: Indicates if data for each wind source is considered valid. See Section 3.6.17 for details.

Status, True Wind: Indicates if data for each wind source is considered valid. See Section 3.6.16 for details.

TFOM GPS: Time Figure Of Merit from the GPS receiver.

TFOM INS: Time Figure Of Merit from INS, if one is provided.

TFOM PTU: Time Figure Of Merit from the Precise Time Unit (PTU).

Time, Day of Year, GPS1: Julian day number that is applicable to the validity of the GPS1 data in the message.

Time, Day of Year, GPS2: Julian day number that is applicable to the validity of the GPS2 data in the message.

Time, Day of Year, INS1: Julian day number that is applicable to the validity of the INS1 data in the message.

Time, Day of Year, INS2: Julian day number that is applicable to the validity of the INS2 data in the message.

Time, Year, GPS1: Four-digit year that is applicable to the validity of the GPS1 data in the message.

Time, Year, GPS2: Four-digit year that is applicable to the validity of the GPS2 data in the message.

Time, Year, INS1: Four-digit year that is applicable to the validity of the INS1 data in the message.

Time, Year, INS2: Four-digit year that is applicable to the validity of the INS2 data in the message.

Time of Data: NAVSSI time tag that indicates time of validity of the data in the message.

Time of Data, GPS1: NAVSSI time tag that indicates time of validity of the GPS1 data in the message.

Time of Data, GPS2: NAVSSI time tag that indicates time of validity of the GPS2 data in the message.

Time of Data, INS1: NAVSSI time tag that indicates time of validity of the INS1 data in the message.

Time of Data, INS2: NAVSSI time tag that indicates time of validity of the INS2 data in the message.

Time of Gyro Reset: The UTC of the fix used by the <> INS in its latest reset.

Time of Gyro Reset, INS1: The UTC of the fix used by INS1 in its latest reset.

Time of Gyro Reset, INS2: The UTC of the fix used by INS2 in its latest reset.

Velocity Down: See “Velocity Vertical”.

Velocity East: East/west component of own ship’s total horizontal velocity. Positive is defined as East. The accuracy of Velocity East is expressed in the Velocity East RMS error.

Velocity East, BFTT: Velocity east as provided in the BFTT message received by NAVSSI.

Velocity East RMS Error: Estimated RMS velocity error along the east axis.

Distribution D Page 11

Velocity North: North/south component of own ship’s total horizontal velocity. Positive is defined as North. The accuracy of Velocity North is expressed in the Velocity North RMS error.

Velocity North, BFTT: Velocity north as provided in the BFTT message received by NAVSSI.

Velocity North RMS Error: Estimated RMS velocity error along the north axis.

Velocity Vertical: Velocity Vertical is the component of own ship’s velocity along the direction of the reference ellipsoid vertical. Positive is defined as down. The accuracy of Velocity Vertical is expressed in the Velocity Vertical RMS error

Velocity Vertical, BFTT: Vertical Velocity as provided in the BFTT message received by NAVSSI.

Velocity Vertical RMS Error: Estimated RMS velocity error along the vertical axis.

Wind Direction, Apparent: Historically was interchanged with relative wind.

Wind Direction, Platform Apparent R: Relative wind referenced to true north.

Wind Direction, Platform Apparent T: Direction of true wind with respect to the ship’s center line. (Platform apparent T is the wind vector resulted from the vector sum of true wind vector and ship’s heading and speed vector).

Wind Direction, Relative: Direction of the wind measured with respect to the ship’s centerline.

Wind Direction, True: Direction relative to true north from which the wind blows.

Wind Sensor, Apparent: Historically was interchanged with relative wind.

Wind Sensor, Relative: Physical source of wind information.

Wind Sensor, True: Physical source of wind information.

Wind Speed, Apparent: Historically was interchanged with relative wind.

Wind Speed, Platform Apparent R: Magnitude of Platform Apparent R wind. This is equivalent to relative wind speed.

Wind Speed, Platform Apparent T: Magnitude of Platform Apparent T wind. (Platform apparent T is the wind vector resulted from the vector sum of true wind vector and ship’s heading and speed vector).

Wind Speed, Relative: Magnitude of relative wind.

Wind Speed, Straight Deck Cross: The component of the wind normal to the ship. A negative (-) value indicates a port crosswind and a positive (+) value indicates a starboard crosswind.

Wind Speed, Straight Deck Head: The component of the wind that is parallel to the ship. A negative (-) value indicates a tailwind and a positive (+) value indicates a headwind.

Wind Speed, True: Magnitude of true wind.

Page 12 Distribution D

3.5 Data Elements Characteristics

In Table 3-1 the Units, Ranges and data Types of the various data elements are provided. The V6 and V7 designations indicate that the specific field has two different Types and/or Units and/or Range designations.

Whether the field name has a V6 qualifier or a V7 qualifier, the definition as provided in section 3.4 still applies.

Table 3-1 Data Elements Characteristics

Field Name Type Units Range Acceleration Down, V6 IEEE 32 bit Floating Point Feet/Second2 -25.0 … 25.0 Acceleration Down, V7 IEEE 64 bit Floating Point Feet/Second2 -25.0 … 25.0 Acceleration East, V6 IEEE 32 bit Floating Point Feet/Second2 -192.0 … 191.9 Acceleration East, V7 IEEE 64 bit Floating Point Feet/Second2 -25.0 … 25.0 Acceleration North, V6 IEEE 32 bit Floating Point Feet/Second2 -192.0 … 191.9 Acceleration North, V7 IEEE 64 bit Floating Point Feet/Second2 -192.0 … 191.9 Attitude, Fox Corpen IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading, BFTT IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading, INS1 IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading, INS2 IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading, V6 IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading, V7 IEEE 64 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading Acceleration, V6 IEEE 32 bit Floating Point Degrees/Second2 -32.0 … 32.0 Attitude, Heading Acceleration, V7 IEEE 64 bit Floating Point Degrees/Second2 -32.0 … 32.0 Attitude, Heading Magnetic North IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Attitude, Heading Magnetic True IEEE 32 bit Floating Point Degrees 0.0. ... 359.99 Attitude, Heading Rate IEEE 32 bit Floating Point Degrees/Second -32.0 … 32.0 Attitude, Heading Rate, BFTT IEEE 32 bit Floating Point Degrees/Second -32.0 … 32.0 Attitude, Heading RMS Error IEEE 32 bit Floating Point Degrees 0.0 … 10.0 Attitude, Heave IEEE 32 bit Floating Point Feet -128.0 … 128.0 Attitude, Pitch, V6 IEEE 32 bit Floating Point Degrees -90.0 … 90.0 Attitude, Pitch, V7 IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Attitude, Pitch Acceleration, V6 IEEE 32 bit Floating Point Degrees/Second2 -32.0 … 32.0 Attitude, Pitch Acceleration, V7 IEEE 64 bit Floating Point Degrees/Second2 -32.0 … 32.0 Attitude, Pitch Rate IEEE 32 bit Floating Point Degrees/Second -32.0 … 32.0 Attitude, Pitch RMS Error IEEE 32 bit Floating Point Degrees 0.0 … 10.0 Attitude, Roll, V6 IEEE 32 bit Floating Point Degrees -90.0 … 90.0 Attitude, Roll, V7 IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Attitude, Roll Acceleration, V6 IEEE 32 bit Floating Point Degrees/Second2 -32.0 … 32.0 Attitude, Roll Acceleration, V7 IEEE 64 bit Floating Point Degrees/Second2 -32.0 … 32.0 Attitude, Roll Rate IEEE 32 bit Floating Point Degrees/Second -32.0 … 32.0 Attitude, Roll RMS Error IEEE 32 bit Floating Point Degrees 0.0 … 10.0 Course IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Course, BFTT IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Current, Drift IEEE 32 bit Floating Point Knots -128.0 … 128.0 Current, Ocean East IEEE 32 bit Floating Point Knots -128.0 … 128.0 Current, Ocean East, BFTT IEEE 32 bit Floating Point Knots -128.0 … 128.0 Current, Ocean North IEEE 32 bit Floating Point Knots -128.0 … 128.0 Current, Ocean North, BFTT IEEE 32 bit Floating Point Knots -128.0 … 128.0 Current, Set IEEE 32 bit Floating Point Degrees 0.0 ... 359.99 Depth Below Keel IEEE 32 bit Floating Point Feet 0.0 … 50,000.0 Depth Below Keel, BFTT IEEE 32 bit Floating Point Feet 0.0 … 50,000.0 GPS, C/No Unsigned 8 bit Integer dB- Hz 0 … 60

Distribution D Page 13

GPS1, C/No Unsigned 8 bit Integer dB- Hz 0 … 60 GPS2, C/No Unsigned 8 bit Integer dB- Hz 0 … 60 GPS, Elevation Mask Angle Signed 32 bit Integer Degrees -90 … +90 GPS, Hardware Channel Unsigned 8 bit Integer Numeric 1 … 24 GPS1, Hardware Channel Unsigned 8 bit Integer Numeric 1 … 24 GPS2, Hardware Channel Unsigned 8 bit Integer Numeric 1 … 24 GPS, J/S Unsigned 8 bit Integer dB 0 … 60 GPS1, J/S Unsigned 8 bit Integer dB 0 … 60 GPS2, J/S Unsigned 8 bit Integer dB 0 … 60 GPS, Satellite Number Unsigned 8 bit Integer Numeric 1 … 32 GPS1, Satellite Number Unsigned 8 bit Integer Numeric 1 … 32 GPS2, Satellite Number Unsigned 8 bit Integer Numeric 1 … 32 Integral of Velocity East, V6 Signed 32 bit Integer Feet 0 … (+231 - 1) Integral of Velocity East, V7 IEEE 64 bit Floating Point Feet -221 … (+221 - 2-10) Integral of Velocity North, V6 Signed 32 bit Integer Feet 0 … (+231 - 1) Integral of Velocity North, V7 IEEE 64 bit Floating Point Feet -221 … (+221 - 2-10) Magnetic Variation IEEE 32 bit Floating Point Radians - … Meteorological, Dew Point IEEE 32 bit Floating Point Celsius -100.0 … 100.0 Meteorological, Humidity, Relative IEEE 32 bit Floating Point Percent 0 … 100 Meteorological, Pressure, Barometric IEEE 32 bit Floating Point Millibars 600.0 … 1200.0 Meteorological, Temperature, Air IEEE 32 bit Floating Point Celsius -100.0 … 100.0 Meteorological, Temperature, Water IEEE 32 bit Floating Point Celsius - 5.0 ... 40.0 Own Ship Distance, V6 Unsigned 32 bit Integer Nautical Miles 0 … 4,294,967,295 Own Ship Distance, V7 IEEE 32 bit Floating Point Nautical Miles 0.0 … 4,294,967,295.0 Position, East RMS Error IEEE 32 bit Floating Point Feet 0.0 … 97,280.0 Position, ECEF, X IEEE 32 bit Floating Point Meter -1.7E38 … +17E38 Position, ECEF, Y IEEE 32 bit Floating Point Meter -1.7E38 … +17E38 Position, ECEF, Z IEEE 32 bit Floating Point Meter -1.7E38 … +17E38 Position, GPS Altitude (Absolute) IEEE 32 bit Floating Point Meter -1.7E38 … +17E38 Position, GPS Altitude (MSL) IEEE 32 bit Floating Point Meter -1.7E38 … +17E38 Position, Latitude IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Position, Latitude, BFTT IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Position, Latitude, GPS1 IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Position, Latitude, GPS2 IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Position, Latitude, INS1 IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Position, Latitude, INS2 IEEE 64 bit Floating Point Degrees -90.0 … 90.0 Position, Longitude IEEE 64 bit Floating Point Degrees -180.0 … 180.0 Position, Longitude, BFTT IEEE 64 bit Floating Point Degrees -180.0 … 180.0 Position, Longitude, GPS1 IEEE 64 bit Floating Point Degrees -180.0 … 180.0 Position, Longitude, GPS2 IEEE 64 bit Floating Point Degrees -180.0 … 180.0 Position, Longitude, INS1 IEEE 64 bit Floating Point Degrees -180.0 … 180.0 Position, Longitude, INS2 IEEE 64 bit Floating Point Degrees -180.0 … 180.0 Position, North RMS Error IEEE 32 bit Floating Point Feet 0.0 … 97,280.0 Position, Radial Error Estimate IEEE 32 bit Floating Point Feet 0.0 … 97,280.0 Position, Vertical (CMD) IEEE 32 bit Floating Point Feet –128.0 … 128.0 Position, Vertical, BFTT IEEE 32 bit Floating Point Feet -20,000.0 … 20,000.0 Position, Vertical, GPS1 IEEE 32 bit Floating Point Feet -20,000.0 … 20,000.0 Position, Vertical, GPS2 IEEE 32 bit Floating Point Feet -20,000.0 … 20,000.0 Position, Vertical, INS1 IEEE 32 bit Floating Point Feet -20,000.0 … 20,000.0

Page 14 Distribution D

Position, Vertical, INS2 IEEE 32 bit Floating Point Feet -20,000.0 … 20,000.0 Position, Vertical, V6 IEEE 32 bit Floating Point Feet -20,000.0 … 20,000.0 Position, Vertical, V7 IEEE 32 bit Floating Point Feet –256.0 … 256.0 Position, Vertical RMS Error IEEE 32 bit Floating Point Feet 0.0 … 97,280.0 Speed, Athwartships IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed, Athwartships, BFTT IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed, Best IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed Log, Calibration IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed Over Ground IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed Through the Water IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed Through the Water, BFTT IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed, Vertical, BFTT IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed, Vertical, V6 IEEE 32 bit Floating Point Knots -128.0 … 128.0 Speed, Vertical, V7 IEEE 64 bit Floating Point Feet/Second -192.0 … 192.0 Status, Antenna (CMD) Unsigned 64 bit Integer N/A See Section 3.6.8 Status, Antenna V7 Unsigned 64 bit Integer N/A See Section 3.6.9 Status, FOAL 1 Unsigned 32 bit Integer N/A See Section 3.6.10 Status, FOAL 2 Unsigned 32 bit Integer N/A See Section 3.6.10 Status, FOAL, Remote Unsigned 32 bit Integer N/A See Section 3.6.10 Status, GPS Unsigned 64 bit Integer N/A See Section 3.6 Status, GPS1 Unsigned 64 bit Integer N/A See Section 3.6.5 Status, GPS2 Unsigned 64 bit Integer N/A See Section 3.6.5 Status, GPS (CMD) Unsigned 64 bit Integer N/A See Section 3.6.6 Status, GPS V6 Unsigned 64 bit Integer N/A See Section 3.6.5 Status, GPS V7 Unsigned 96 bit Integer N/A See Section 3.6.7 Status, INS V6 (OD17) Unsigned 32 bit Integer N/A See Section 3.6.11 Status, INS V6 (OD19) Unsigned 64 bit Integer N/A See Section 3.6.12 Status, INS V7 Unsigned 64 bit Integer N/A See Section 3.6.13 Status, Magnetic Variation Unsigned 32 bit Integer N/A See Section 3.6.15 Status, NAVSSI Unsigned 64 bit Integer N/A See Section 3.6.1 Status, NAV1 Unsigned 64 bit Integer N/A See Section 3.6.2 Status, NAV2 Unsigned 64 bit Integer N/A See Section 3.6.3 Status, NAV2 (CMD) Unsigned 64 bit Integer N/A See Section 3.6.4 Status, OSD Unsigned 32 bit Integer N/A See Section 3.6.14 Status, Relative Wind Unsigned 32 bit Integer N/A See Section 3.6.17 Status, True Wind Unsigned 32 bit Integer N/A See Section 3.6.16 TFOM GPS Unsigned 8 bit Integer Numeric 0 ... 15 TFOM INS Unsigned 8 bit Integer Numeric 0 ... 15 TFOM PTU Unsigned 8 bit Integer Numeric 0 ... 15 Time, Day of Year Unsigned 32 bit Integer Days 1 … 366 Time, Day of Year, GPS1 Unsigned 32 bit Integer Days 1 … 366 Time, Day of Year, GPS2 Unsigned 32 bit Integer Days 1 … 366 Time, Day of Year, INS1 Unsigned 32 bit Integer Days 1 … 366 Time, Day of Year, INS2 Unsigned 32 bit Integer Days 1 … 366 Time, Year Unsigned 32 bit Integer Years 1993 … 9999 Time, Year, GPS1 Unsigned 32 bit Integer Years 1993 … 9999 Time, Year, GPS2 Unsigned 32 bit Integer Years 1993 … 9999 Time, Year, INS1 Unsigned 32 bit Integer Years 1993 … 9999 Time, Year, INS2 Unsigned 32 bit Integer Years 1993 … 9999 Time of Data IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0

Distribution D Page 15

Time of Data, GPS1 IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Time of Data, GPS2 IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Time of Data, INS1 IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Time of Data, INS2 IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Time of Gyro Reset (TGR) IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Time of Gyro Reset (TGR), INS1 IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Time of Gyro Reset (TGR), INS2 IEEE 64 bit Floating Point Seconds 0.0 … 86,401.0 Velocity East, BFTT IEEE 32 bit Floating Point Knots –128.0 … 128.0 Velocity East, V6 IEEE 32 bit Floating Point Knots –128.0 … 128.0 Velocity East, V7 IEEE 64 bit Floating Point Knots –128.0 … 128.0 Velocity East RMS Error IEEE 32 bit Floating Point Feet/Second 0.0 … 32.0 Velocity North, BFTT IEEE 32 bit Floating Point Knots –128.0 … 128.0 Velocity North, V6 IEEE 32 bit Floating Point Knots –128.0 … 128.0 Velocity North, V7 IEEE 64 bit Floating Point Knots –128.0 … 128.0 Velocity North RMS Error IEEE 32 bit Floating Point Feet/Second 0.0 … 32.0 Velocity Vertical, BFTT IEEE 32 bit Floating Point Knots –128.0 … 128.0 Velocity Vertical, V6 IEEE 32 bit Floating Point Knots –128.0 … 128.0 Velocity Vertical, V7 IEEE 64 bit Floating Point Feet/Second –192.0 … 192.0 Velocity Vertical RMS Error IEEE 32 bit Floating Point Feet/Second 0.0 … 32.0 Wind Direction, Platform Apparent R IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Wind Direction, Platform Apparent T IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Wind Direction, Relative IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Wind Direction, True IEEE 32 bit Floating Point Degrees 0.0 … 359.99 Wind Sensor, Relative Unsigned 32 bit Integer N/A 0 = Unknown

1 = Port Bird 2 = Starboard Bird 3 = Forward Bird >3 = Reserved

Wind Sensor, True Unsigned 32 bit Integer N/A 0 = Unknown 1 = Port Bird 2 = Starboard Bird 3 = Forward Bird 4 = None (Calculated ) >4 = Reserved

Wind Sensor, True, V6 Unsigned 32 bit Integer N/A 0 = Unknown 1 = Port Bird 2 = Starboard Bird 3 = Forward Bird >3 = Reserved

Wind Speed, Platform Apparent R IEEE 32 bit Floating Point Knots 0.0 … 200.0 Wind Speed, Platform Apparent T IEEE 32 bit Floating Point Knots 0.0 … 200.0 Wind Speed, Relative IEEE 32 bit Floating Point Knots 0.0 … 200.0 Wind Speed, Relative , V6 IEEE 32 bit Floating Point Knots 0.0 … 100.0 Wind Speed, Straight Deck Cross IEEE 32 bit Floating Point Knots 0.0 … 200.0 Wind Speed, Straight Deck Head IEEE 32 bit Floating Point Knots 0.0 … 200.0 Wind Speed, True IEEE 32 bit Floating Point Knots 0.0 … 200.0 Wind Speed, True, V6 IEEE 32 bit Floating Point Knots 0.0 … 100.0

Page 16 Distribution D

3.6 Status Elements

3.6.1 NAVSSI Status Element

Table 3-2 provides definitions for the bits in the NAVSSI Status word contained within the NAVSSI Navigation Message. The NAVSSI Status field contains availability information for the RTSs, GPS Receivers, DCS/NCS, and INSs; validity information for various navigation values, including Navigation Source Integration (NSI); Time Figure of Merit (TFOM), and fault information.

NAVSSI Status is a 64-bit word with Bit 0 equivalent to LSB.

Table 3-2 NAVSSI Status

Description Bit Value RTS 1 Available (RTS1 is installed on the ship. RTS1 may or may not be operational).

0 0 = RTS Not Installed 1 = RTS Installed

RTS 2 Available (RTS2 is installed on the ship. RTS2 may or may not be operational).

1 0 = RTS Not Installed 1 = RTS Installed

GPS Receiver in RTS 1 Available (A GPS Receiver in RTS1 exists and operational)

2 0 = GPS Receiver in RTS Down 1 = GPS Receiver in RTS Up

GPS Receiver in RTS 2 Available (A GPS Receiver in RTS 2 exists and operational)

3 0 = GPS Receiver in RTS Down 1 = GPS Receiver in RTS Up

DCS Operational (DCS heart beat was received by the

RTS)

4 0 = DCS Down 1 = DCS Up

North, East RMS Error Valid 5 0 = Invalid 1 = Valid

Vertical Position RMS Error Valid 6 0 = Invalid 1 = Valid

Radial Error Estimate Valid 7 0 = Invalid 1 = Valid

North, East Velocity RMS Error Valid

8 0 = Invalid 1 = Valid

Down Velocity RMS Error Valid 9 0 = Invalid 1 = Valid

Roll, Pitch RMS Error Valid 10 0 = Invalid 1 = Valid

Heading RMS Error Valid 11 0 = Invalid 1 = Valid

Time of Gyro Reset Valid 12 0 = Invalid 1 = Valid

Latitude, Longitude Valid 13 0 = Invalid 1 = Valid

Vertical Position Valid 14 0 = Invalid 1 = Valid

Velocity North, East Valid 15 0 = Invalid 1 = Valid

Velocity Down Valid 16 0 = Invalid 1 = Valid

Acceleration North, East Valid 17 0 = Invalid 1 = Valid

Distribution D Page 17

Acceleration Down Valid 18 0 = Invalid

1 = Valid Integral of Velocity North, East Valid 19 0 = Invalid

1 = Valid Course Valid 20 0 = Invalid

1 = Valid Speed Through the Water Valid 21 0 = Invalid

1 = Valid Calibration for Speed Log Valid 22 0 = Invalid

1 = Valid Depth Below Keel Valid 23 0 = Invalid

1 = Valid Ocean Current North, East Valid 24 0 = Invalid

1 = Valid Roll, Pitch Valid 25 0 = Invalid

1 = Valid Heading Valid 26 0 = Invalid

1 = Valid Roll, Pitch Rate Valid 27 0 = Invalid

1 = Valid Heading Rate Valid 28 0 = Invalid

1 = Valid Roll, Pitch Acceleration Valid 29 0 = Invalid

1 = Valid Heading Acceleration Valid 30 0 = Invalid

1 = Valid NSI Valid (Validity Indication of the position, velocity, and acceleration data produced by the NSI function of

NAVSSI)

31 0 = Invalid 1 = Valid

TFOM

(An indication of the accuracy of the time data)

32-35 1 = Better than 1 nanoseconds (ns) 2 = 1 ns to 10 ns 3 = 10 ns to 100 ns 4 = 100 ns to 1 microseconds (s) 5 = 1 s to 10 s 6 = 10 s to 100 us 7 = 100 s to 1 ms 8 = 1 ms to 10 ms 9 = Greater than 10 ms or fault 10 – 14 = Unused 15 = No valid time is available

Time Valid (Indicates validity of the time tag)

36 0 = Invalid 1 = Valid

Reference Point for Position and Velocity

37-39 0 = OSRP

1 = INS 1 Position 2 = INS 2 Position 3 = GPS Antenna 1 4 = GPS Antenna 2 5 = Other 6 -7 = Reserved for future

Page 18 Distribution D

Best INS 40 0 = INS 1 has been chosen as being more accurate than INS 2

1 = INS 2 has been chosen as being more accurate than INS 1 RTS 1 Operation Status (Heart beat and/or reflective memory communication is confirmed)

41 0 = Not Operational 1 = Operational

RTS 2 Operation Status (Heart beat and/or reflective memory communication is confirmed)

42 0 = Not Operational 1 = Operational

RTS 1 Time Fault (Fault in the PTU in RTS 1)

43 0 = No Time Fault 1 = Time Fault

RTS 2 Time Fault (Fault in the PTU in RTS 2)

44 0 = No Time Fault 1 = Time Fault

INS data to RTS 1 Available (An INS is attached to RTS 1 and operational)

45 0 = No 1 = Yes

INS data to RTS 2 Available (An INS is attached to RTS 2 and operational)

46 0 = No 1 = Yes

Originating RTS 47 See Section 3.6.1.1 Leap Second Bit 48 0 = Leap Second will not occur within next 24 hours

1 = Leap second will occur within next 24 hours Best INS Valid 49 0 = Invalid

1 = Valid Simulated Data (Indicates if the data in the message is simulated)

50 0 = No 1 = Yes

FWD INS Failure 51 0 = No 1 = Yes

AFT INS Failure 52 0 = No 1 = Yes

RTS 3 Available 53 0 = No 1 = Yes

GPS Receiver in RTS 3 Available (A GPS Receiver in RTS 3 exists and operational)

54 0 = No 1 = Yes

RTS 3 Time Fault (Fault in the PTU in RTS 3)

55 0 = No 1 = Yes

INS data to RTS 3 Available (An INS is attached to RTS 3 and operational)

56 0 = No 1 = Yes

Originating RTS (Alt) 57 See Section 3.6.1.1 STW with SOG data (Indicates whether the STW element is populated with SOG)

58 0 = No 1 = Yes

Spare 59 Reserved for future use Total number of display systems on board (The total number of DCSs and NRSs systems)

60 – 63 0 – 15

Distribution D Page 19

3.6.1.1 Usage of Originating RTS and Originating RTS (Alt) Fields

Table 3-3 provides information about the usage of the Originating RTS and Originating RTS (Alt) Fields.

Table 3-3 The Originating RTS And Originating RTS (Alt) Fields

Message Originated By Indicators

Originating RTS Originating RTS (Alt)

RTS 1 0 0

RTS 2 1 0

RTS 3 0 1

Reserved 1 1

3.6.2 NAV Status 1 Field Descriptions

Table 3-4 provides definitions and descriptions for the bits in the NAV Status 1 word. The NAV Status 1 field contains availability information for the RTSs, GPS VME Receiver Cards (GPSs), NCS, and INSs; validity information for various navigation values, including Navigation Source Integration (NSI); Time Figure Of Merit (TFOM), and fault information.

NAV Status 1 word is a 64-bit word with Bit 0 equivalent to LSB.

Table 3-4 NAV Status 1 Word

Description Bit Value Definition GPS Receiver in RTS1 Available

0 0 = GPS Receiver in RTS Down 1 = GPS Receiver in RTS Up

A GPS Receiver in RTS1 exists and operational

GPS Receiver in RTS2 Available

1 0 = GPS Receiver in RTS Down 1 = GPS Receiver in RTS Up

A GPS Receiver in RTS2 exists and operational

GPS Receiver in RTS3 Available

2 0 = GPS Receiver in RTS Down 1 = GPS Receiver in RTS Up

A GPS Receiver in RTS3 exists and operational

NCS Available 3 0 = NCS Down 1 = NCS Up

NCS is operational as confirmed by reception of the periodic heart beat generated by the NCS.

North RMS Error 4 0 = Invalid 1 = Valid

Data Validity Indication

East RMS Error 5 0 = Invalid 1 = Valid

Data Validity Indication

Vertical Position RMS Error

6 0 = Invalid 1 = Valid

Data Validity Indication

Radial Error Estimate 7 0 = Invalid 1 = Valid

Data Validity Indication

Velocity North RMS Error 8 0 = Invalid 1 = Valid

Data Validity Indication

Velocity East RMS Error 9 0 = Invalid 1 = Valid

Data Validity Indication

Velocity Vertical RMS Error

10 0 = Invalid 1 = Valid

Data Validity Indication

Roll RMS Error 11 0 = Invalid 1 = Valid

Data Validity Indication

Pitch RMS Error 12 0 = Invalid

Data Validity Indication

Page 20 Distribution D

Heading RMS Error 13 0 = Invalid

1 = Valid Data Validity Indication

Time of Gyro Reset 14 0 = Invalid 1 = Valid

Data Validity Indication

Position 15 0 = Invalid 1 = Valid

Data Validity Indication

Vertical Position 16 0 = Invalid 1 = Valid

Data Validity Indication

Velocity North 17 0 = Invalid 1 = Valid

Data Validity Indication

Velocity East 18 0 = Invalid 1 = Valid

Data Validity Indication

Velocity Vertical 19 0 = Invalid 1 = Valid

Data Validity Indication

Acceleration North 20 0 = Invalid 1 = Valid

Data Validity Indication

Acceleration East 21 0 = Invalid 1 = Valid

Data Validity Indication

Acceleration Down 22 0 = Invalid 1 = Valid

Data Validity Indication

Integral of Velocity North 23 0 = Invalid 1 = Valid

Data Validity Indication

Integral of Velocity East 24 0 = Invalid 1 = Valid

Data Validity Indication

Course 25 0 = Invalid 1 = Valid

Data Validity Indication

Speed Through the Water 26 0 = Invalid 1 = Valid

Data Validity Indication

Best Speed 27 0 = Invalid 1 = Valid

Data Validity Indication

SOG 28 0 = Invalid 1 = Valid

Data Validity Indication

Calibration for Speed Log 29 0 = Invalid 1 = Valid

Data Validity Indication

Athwartships Speed 30 0 = Invalid 1 = Valid

Data Validity Indication

Vertical Speed 31 0 = Invalid 1 = Valid

Data Validity Indication

Ownship Distance 32 0 = Invalid 1 = Valid

Data Validity Indication

Water Temperature 33 0 = Invalid 1 = Valid

Data Validity Indication

Depth Below Keel 34 0 = Invalid 1 = Valid

Data Validity Indication

Ocean Current North 35 0 = Invalid 1 = Valid

Data Validity Indication

Ocean Current East 36 0 = Invalid 1 = Valid

Data Validity Indication

Roll 37 0 = Invalid 1 = Valid

Data Validity Indication

Pitch 38 0 = Invalid

Distribution D Page 21

Heading 39 0 = Invalid

1 = Valid Data Validity Indication

Roll Rate 40 0 = Invalid 1 = Valid

Data Validity Indication

Pitch Rate 41 0 = Invalid 1 = Valid

Data Validity Indication

Heading Rate 42 0 = Invalid 1 = Valid

Data Validity Indication

Roll Acceleration 43 0 = Invalid 1 = Valid

Data Validity Indication

Pitch Acceleration 44 0 = Invalid 1 = Valid

Data Validity Indication

Heading Acceleration 45 0 = Invalid 1 = Valid

Data Validity Indication

NSI 46 0 = Invalid 1 = Valid

Validity Indication of the position, velocity, and acceleration data produced by the NSI function of

NAVDDX.

Time 47 0 = Invalid 1 = Valid

Validity of the time tag

Best INS Selection 48-49 00 = Reserved for future use 01 = INS1 has been chosen as being more accurate than INS2 or INS3 10 = INS2 has been chosen as being more accurate than INS1 or INS3 11 = INS3 has been chosen as being more accurate than INS1 or INS2

Which of the two or three INSs is selected as best source

RTS1 Status 50 0 = Not Operational 1 = Operational

Heart beat and/or reflective memory communication is confirmed

RTS2 Status 51 0 = Not Operational 1 = Operational

Heart beat and/or reflective…