THE CDNU

The C-12284/A Control Display Navigation Unit (CDNU) is the primary control and display interface for the EGI-based navigation system. The CDNU, installed on the RIO’s left-hand console, is the bus controller for the NAVBUS, controlling the exchange of digital information between the EGI, the CSDC(R), and itself. The Computer Address Panel (CAP) in the F-14B(U) still serves a function, but no navigation inputs are made through it anymore. The Navigation functions of the CAP either do not work or the options in the drum have been replaced to serve other functions.

Associated equipment for navigation is: The F-14 Mission Computer (FMC), the H-764G Embedded GPS/INS (EGI), the Computer Signal Data Converter (Replacement) [CSDC(R)], the A/A24G-39 Attitude Heading Reference Set (AHRS), the C-12284/A Control Display Navigation Unit (CDNU), and a Signal Data Converter (SDC).

CDNU Display

Electronic pages and a page tree structure are used on a Cathode Ray Tube (CRT) (1) to display information and provide control of various navigation system functions. Pages are accessed by pressing the function keys, dedicated keys, arrow keys, or Line Select Keys (LSKs) as required. Each page consists of an eight−line (22 characters per line) display. Not all lines will be utilized for each page. Lines 1, 3, 5, and 7 are data lines, and are divided into two parts — left screen and right screen — that correspond to the adjacent LSK. The title, information, and annunciation lines are located between the data lines. Annunciation messages, displayed on the annunciation line, alert the operator to conditions requiring attention.

CDNU Front Panel

Line Select Keys

Eight Line Select Keys (LSKs) (2) are used to initiate functions selected, insert data from the scratchpad, change the mode of operation, or change display to the page indicated when a Go To Arrow is displayed. The LSKs will operate in a rotary or toggle manner depending on the mode or function indicated on the display. Rotary operation will be active if there are more than two options available to the RIO (e.g., AIDED/ UNAIDED/GPS), and toggle operation will be active if there are only two options (e.g., ON/OFF). Options are selected by pressing the LSK adjacent to the appropriate displayed message. Data is first entered into the scratchpad from the keyboard, and is then entered into the proper data line by depressing the appropriate LSK.

Alphanumeric Keys

Alphanumeric keys (3) allow the selection of either numbers or letters for entry into the scratchpad. The "N" "S", "E", and "W" keys are highlighted so they may be easily located when entering position in Latitude/Longitude coordinates.

Function Keys

The function keys, F1 through F7 (4), allow the operator to perform specific, aircraft related functions without accessing a particular CDNU page. The Figure below lists the function associated with each key. Depressing the MENU Key displays the MENU Page, a quick reference guide to the available functions.

CDNU Function MENU

Dedicated Select Keys

The Dedicated Select Keys (5) allow the RIO to call up and display navigation data on the CDNU. The STAT (status), MENU, and IDX (index) dedicated select keys permit access to a variety of information applicable to the general flight operation and maintenance of the navigation system at any time.

Scratchpad

The scratchpad is the bottom line on the display,(6), enclosed by brackets, and is used to display data entered using the alphanumeric keys. It is a buffer to hold all keystrokes prior to executing the input. Error messages will also be displayed in the scratchpad if operational or data entry conditions are not met. Incorrect scratchpad entries are cleared with the CLR key. The scratchpad is automatically cleared when the system accepts valid inputs.

Page Scrolling

Arrow keys (7) are provided to permit vertical and horizontal scrolling of pages [e.g., switching between the EGI Start 1/2 and EGI Start 2/2 pages (vertical), and between RNAV Pages (horizontal)]. Special arrow characters are displayed adjacent to the left-hand scratchpad bracket to indicate the type of scrolling available.

Vertical scrolling is accomplished by pressing the "↑" and "↓" arrow keys. Pressing the "↑" arrow key moves one toward the beginning of a set of data (e.g., a lower numbered intercept). Lateral page scrolling is accomplished by pressing the "←" and "→" arrow keys. Holding the arrow keys causes page scrolling to continue until the key is released.

Clear Key

The CLR (8) (clear) key is considered a special function control key. When the key is pressed momentarily, the last character displayed in the scratchpad is deleted. Holding down the clear key will clear all characters in the scratchpad.

Error messages can be cleared by depressing the CLR key when the message appears. The key will also clear certain annunciation messages when the scratchpad is blank and annunciation messages are displayed on line six of the display.

Common Symbology

CDNU Standard Display Symbols

Start Page	RNAV Page

Icon	Meaning
	Go To Arrow. Pushing the Line Select Key access a different page. (Arrow points toward Key).
	Pushing the Line Select Key will select the item or enable the mode. (Arrow points toward text).
	Function is Enabled.
	Alternate selections are available.
	Check status pages for BIT failures.
	No computed data is available or meaningful.
	Data entry from the scratchpad is possible/required.
	Vertical page or line scrolling is possible.
	Lateral page scrolling is possible.
	Lateral and Vertical page scrolling is possible.

The CDNU flight plan and Steering sources

The F-14B(U)’s CDNU flight plan system is built to manage multiple routes while allowing both preplanned and dynamic navigation during a mission. The system can store up to twelve separate flight plans, each composed of a sequence of waypoints that define the intended path of flight. These waypoints are not organized by their numerical identifiers, but strictly by the order in which they are intended to be flown, meaning the order in which the waypoints are displayed on the CDNU FPLN page. The waypoint ID itself, or the waypoint label, has no influence on its position within a given flight plan.

Waypoints are divided into two main categories: preset and impromptu. Preset waypoints occupy identifiers one through fifty and are typically loaded via mission data prior to flight, while impromptu waypoints begin at fifty-one and are created by the crew in real time or by the system to provide turn anticipation. This separation allows the crew to distinguish between planned navigation points and those generated on the fly without affecting how they are sequenced within the active route. The active flight plan route, and the sequence in which waypoints are meant to be flown, can be changed at any time during flight by copying, inserting, and/or deleting redundant waypoints.

The F-14B(U)’s navigation system provides four types of steering output. Because of the B(U)’s system architecture, there are essentially two steering sources: first, the EGI, which is overall responsible for positional data, and second, the F-14’s Mission Computer (FMC). The EGI is controlled by the CDNU, and its steering modes are selected through the CDNU.

The FMC is responsible for attack steering modes such as GGW LP and TGT steering, but also for DEST steering.

EGI Steering

As the aircraft progresses along a flight plan, waypoint sequencing is governed by the selected mode. In AUTO mode, the system automatically advances to the next waypoint once certain criteria are met, such as passing a defined proximity threshold. OFLY (overfly) mode requires the aircraft to pass directly over, or very near, the waypoint before sequencing occurs; this is useful in low-level navigation, for example, where overflight of a precise point is crucial. In both modes, once a waypoint has been passed, it transitions into a history state, allowing the crew to track what has already been flown. The third mode is Manual Mode (MAN). In this mode, the flight plan does not sequence automatically. Steering is only provided to the currently active waypoint shown on the first FPLN page. The only way to advance the flight plan in this mode is by using the DIR function located on the CDNU.

DEST Steering

DEST steering is entirely separate from the CDNU flight plan and can be used independently of the EGI fly-to point. DEST steering for the RIO is not to be confused with DEST steering set on the pilot’s PDCP. In DEST steering, the RIO may select one waypoint from the CDNU’s flight plan to provide steering to. This can be achieved through the CDNU WP EDIT page, or through the PTID’s DEST rotary on PB 8 and PB 9.

BDHI Steering

BDHI steering can be entirely separate from DEST and EGI steering and is only presented on the BDHI. Through the BDHI steering page on the CDNU, accessed via the F4 key, the RIO can direct the BDHI to either synchronize with HUD and HSD steering, provide launch point and target steering to the next launch GGW target, or provide steering to a CDNU flight plan waypoint. Like DEST steering, no AUTO or OFLY sequencing occurs.

TACAN Steering

TACAN steering can be selected through the pilot’s or RIO’s TACAN command panel. The TACAN command panel cycles between TACAN and EGI steering. In TACAN steering, the HUD and HSD provide steering to the selected TACAN station. If DEST steering is selected on the PDCP, the HSD will not display it; only TACAN selected on the PDCP will show TACAN steering on the HSD. The BDHI is not affected if TACAN steering is selected and the RIO has the BDHI set to EGI fly-to or FPLN waypoint steering.

History Waypoints

The five waypoints most recently passed are also maintained in the flight plan. These waypoints along with the associated altitude, Flight Mode and planned time of arrival may be reviewed by scrolling the Flight Plan page with the up arrow key. These waypoint definitions may not be edited or deleted but they may be used with Direct-To.

Data Entry

This section describes acceptable data entry formats, valid data ranges and display formats.

All navigation−related quantities may be displayed in either metric or English units unless specifically stated elsewhere (e.g., altitude related quantities, which are always displayed in feet and feet/minute). When metric units are chosen the unit labels are changed appropriately. Generally speaking data is always entered into the scratchpad (SP) before the data-line for data entry is selected with a Line Select Key (LSK).

Entry and Display of Waypoints

The F−14B uses a common numbering scheme for display of waypoints. The CDNU, PTID (including the LTS display), and HUD will all display the same two digit number assigned to each waypoint. When a flight plan is first activated, the waypoints are assigned numbers from 01 to 50 in flight plan order. When new waypoints are added, they are assigned numbers sequentially beginning with number 51. When waypoints are deleted, the remaining waypoints retain their original number. he RIO may change the waypoint number of a specific waypoint using LSK 3 on the Waypoint Edit 1/2 page. (Link)

💡 Duplicate waypoint display IDs can be entered and will be displayed.

Flight plan waypoints and other horizontal locations are entered in one of three basic formats:

User Define Label (UDL) — Waypoints can be inserted into the flight plan via their (User Defined Label). Any UDL waypoint stored on the MDL can be entered into the SP and inserted into the FPLN.

ICAO Identifier — position labeled with up to a 5 character alphanumeric. The appropriate data are extracted from a database contained in the MDL or downloaded to CDNU nonvolatile memory

Position coordinates — either as a latitude/ longitude waypoint pair or as a Military Grid Reference System coordinate.

Entry and Display of Latitude/Longitude Waypoints

Latitude/longitude waypoints are entered in the form of degrees and decimal minutes (DMM). The required format is an "N" or "S" followed by four digits (with a decimal point and up to three additional digits optional), followed by "E" or "W" followed by five digits (with a decimal point and up to three additional digits optional). Leading zeros are required as no deliminator are used between degrees and minutes. All waypoints are stored, and calculations made, using thousandth of a minute precision.

💡 Do not enter spaces between degrees and minutes or between latitude and longitude entries. Do not put a "/" or any other character between entries. A typical entry will have the form: "Nddmm.mmmWdddmm.mmm" (where dd = degrees and mm = minutes) with digits to the right of the decimal points optional.

Latitude/longitude waypoints are displayed left-justified to the nearest tenth of a minute on all CDNU pages, except on the RNAV Pages and the Waypoint Edit pages where thousandths of minutes are displayed. Coordinates are displayed based on RIO selection of any of the following formats using LSK3 on the RNAV page.

• DMM − Degrees, Minutes, fractional minutes to 0.0001
• DMS − Degrees, Minutes, Seconds, fractional seconds to 0.01
• MGRS − Military Grid Reference System Coordinates Tactical Display Enhancements

DMM and MGRS coordinate formats are available for entry and display. MGRS and DMM formats can be entered in Scratch Pad (SP) on FPLN and WP Edit pages. Only valid formats are entered after selection. Invalid formats will remain in the SP.

DMS coordinates can only be entered through the high precision coordinate edit display page, DMS coordinates can be displayed via LSK 5 on the WP edit page, or via LSK 3 on the RNAV INAV page

MGRS, DMM and DMS Coordinate display can be toggled between on the RNAV page. Selection of any of these formats on the CDNU controls the format of coordinates on the PTID, hooked WP position coordinates on the PTID NVD WP page, and LANTIRN displays.

High Precision Coordinate Edit

The exception to the above scheme is on the High Precision Coordinate Edit page. Depressing the F3 key when on the Flight Plan or Waypoint Edit 1/2 page calls up the page. This page permits the entry of coordinates to either a ten−thousandth of a minute, or a hundredth of a second. The RIO selects the format by choosing either DMM or DMS with LSK 1. Due to space limitations, spaces and symbols for degrees, minutes, and seconds are eliminated. After coordinates are entered, selecting LSK 5 returns the CDNU to the originating page.

💡 The format for displaying position (DMM, DMS, or MGRS) on the cockpit displays is selected using LSK 3 on the RNAV INAV page of the CDNU. LSK 1 on the High Precision Edit page of the CDNU only controls the data entry mode on that page.

Entry and Display of Military Grid Reference System Waypoints

Military Grid Reference System (MGRS) coordinates are entered as three components:

1. Grid zone designation
2. Meter square identification
3. Grid coordinates

Display format for MGRS waypoints on the WP EDIT and FPLN pages is the grid zone designation followed by one space followed by the 100,000 meter square identification followed by a space followed by the grid coordinates. Six-digit grid coordinates (i.e., 100 meter precision) are used everywhere except on the Area Navigation pages and the Waypoint Data page where ten-digit coordinates (1 meter precision) are used. This yields roughly the same display precision used in the latitude/longitude format.

Data For?/Copy What?

Waypoints, and all their associated data, may be copied in their entirety by using Function Key 7. Pressing F7 alternately writes "DATA FOR?" and "COPY WHAT?" into the scratchpad. "DATA FOR?" permits access to the detailed Waypoint Data page, and "COPY WHAT?" copies a waypoint with all associated attributes into the scratchpad.

Deletion of Data

Most data entry fields may have the associated data deleted by entering a dash "-" in the scratchpad and pressing the LSK adjacent to the desired field. The primary exceptions are waypoints with user supplied names (i.e., those with a slash ("/") as the lead character). These must have the name removed by depressing the "/" key followed by the LSK adjacent to the waypoint. Once this is accomplished, the waypoint can be deleted using the dash.

CDNU Pages

The following section will show all CDNU Pages available as well as highlight possible CDNU actions.

Index Page

STEP 1: Access the IDX Page

(1) Access the Start Page.

(2) Zeroize Page.

(3) Time Selection (No Function).

(4) System Test (No Function).

(5) Mission Data Loader Page (Loading of Flight Plans).

(6) Mark List Page (Shows all Marked Coordinates).

(7) Hold Page (Programming of Holding Patterns).

(8) Intercept Page (Programming of Intercepts).

Start Page 1/2

STEP 1: Go to the IDX Page

STEP 2: Press LSK 1 to access the START page

(1) The GPS initializes at the shutdown position. Entering a new position in the scratchpad will allow the GPS to acquire satellites faster.

(2) Present position of aircraft. Arrow ( ->) indicates initialization mode can be enabled with LS key 1.

(3) Enter date from SP; Date and day of week.

(4) Time; Enter time from SP; enable time display.

(5) Horizontal datum name and number.

(6) Ground track.

(7) Ground Speed.

Start Page 2/2

STEP 1: Access the IDX Page.

STEP 2: Press LSK 1 to access the START page.

STEP 3: Press the arrow down key to switch to START page 2/2.

(1) FOM: GPS Figure of Merit

(2) PTID NAV MODE SEL Switch position:

• NAV
• GND
• CV
• AHRS
• IMU
• OFF

(3) Number of Satellites.

(4) Restart Alignment: Returns EGI to Initialize and then to the EGI chosen alignment mode.

(5) Press LSK 4 to access the CV Manual Align page.

(6) EGI Operation Mode:

• Off
• Initialize
• Gyro Compass
• Stored Heading
• SINS In Motion Align (IMA)
• SINS Stored Heading
• GPS IMA
• Manual IMA
• Air Data IMA

(7) Blended Align Quality in nm/hr.

(8) Alignment time.

(9) Position Solution: GPS; Blended/Aided; Blended/Unaided; Free Inertial.

MDL START Page

STEP 1: Press IDX Key

STEP 2: Press LSK 1 on IDX page to access START page

STEP 3: Vertical scroll until MDL START page

The Mission Data Loader (MDL) provides bulk storage of mission essential data. The Data Transfer Module (DTM), can be loaded in the Mission Editor with up to 12 flight plans, Pre-Planned Missions for JDAM employment and countermeasure profiles for the ALE-47 CDMS.

The MDL Start page is accessed by scrolling up from the EGI Start 1/2 page or down from the EGI Start 2/2 page. Display line 3 contains the MDL cartridge label and date stamp; display line 3 is blank if no cartridge is installed.

(1) Indicates data is from the Revisionary Database.

(2) Name of current Flight Plan.

(3) Mag Var Date.

(4) Erases currently loaded flight plan.

(5) Database validity dates.

(6) Date of the currently loaded flight plan.

(7) Date of the currently loaded mag var table.

(8) LOAD accesses the FPLN select page.

MDL Page

MDL STEP 1: Press IDX Key

STEP 2: Press LSK 5 on IDX page to access MDL page

The MDL Page provides the RIO with the ability to search the entire database of waypoints stored in the MDL, as well as the ability to load different flight plans.

(1) Waypoint Search Page

(2) Name of inserted cartridge.

(3) Load FPLN page (Permits Loading of one of the up to 12 Flight Plans).

(4) Flight Plan Date.

(5) Current Mission Date.

Flight Plan Select Page

FP STEP 1: Press IDX Key

FP STEP 2: Press LSK 5 on IDX page to access MDL page

STEP 3: On MDL Page press LSK 3 to select Flt Pln select page

Flight plan selection is accomplished from the FPLN Select Pages of the CDNU. These pages may be accessed from either the MDL Start page or the MDL page. To activate a specific flight plan, press the LSK adjacent to the selected flight plan. A check mark will be displayed adjacent to the LSK indicating the selection, and FP DATA LOADING will be annunciated on display line 7.

Up to 12 flight plans can be stored on the MDL and accessed via the Flt Pln Select page 1/2 and 2/2. Each flight plan can store 50 pre-planned waypoints.

(1) With LSK 1-3 and 5-7 the desired flight plan can be selected, once selected a check mark is displayed instead of an arrow. The currently active Flight plan has a * next to it.

(2) With the vertical scroll keys Flt Pln Select 2/2 can be accessed.

(3) LSK 8 allows for the loading of the desired flight plan. A "CONFIRM FPLN ACTIVATE" message will be displayed in the scratchpad. Depressing LSK 8 again will then load the flight plan.

Flight Plan Page

STEP 1: Press FPLN Key

(1) Command Course to Active Waypoint.

(2) Indicates course is Active Waypoint. Just below is the Active waypoint.

(3) Assigned altitude for waypoint passage.

(4) Toggles between: EXPAND (2 waypoints per page); COMPACT (4 waypoints per page).

(5) Current vertical angle.

(6) Toggles between flight modes (non-functional).

(7) Planned Time of arrival.

(8) Toggles between AUTO; OFLY; and MAN leg sequencing.

(9) Parallel Course Offset input.

💡 Auto Leg sequencing will "LEAD" turns as required to maintain the flight path within notional airway boundaries and is not recommended for low level navigation because of this feature.

Waypoint Search Page

WP STEP 1: Press IDX Key

STEP 2: Press MDL on LSK 5

STEP 3: Press Waypoint search on LSK2

(1) ICAO identifiers can be accessed from the Waypoint Search page. Search of the database can be accomplished by waypoint type, (TACAN, VOR, VORTAC, Airports, or All), or by entering a partial or complete ICAO Identifier.

(2) Enter ICAO Identifier into SP and press LSK8 to search for waypoint.

Once the desired waypoint has been identified it can be selected by pressing the adjacent LSK. Using the F7 COPY WHAT?/DATA FOR? function lets the operator copy the coordinates and insert them as desired for example into the flight plan.

Attach User Defined Label

Label STEP 1: Press FPLN Key

(1) Enter UDL with the keyboard keys

(2) To enter a UDL the text has to be lead by a "/" up to 5 characters can be in a UDL, if more characters are entered they are not inserted

(3) Pressing the LSK next to the desired waypoint will insert the UDL

(4) To delete a UDL type a "/" into the SP and repeat step 3

FPLN Insert Initial Waypoint

When the flight plan has been erased, the current integrated navigation solution of present position is inserted as the first history waypoint and the Flight Plan page indicates "*End of Flight Plan" in lieu of the active waypoint. To insert a waypoint into the flight plan:

1. Enter the desired waypoint (Position, ICAO ID, or ID/Bearing/Distance) into the scratchpad.

2. Press the left LSK at which "*End of Flight Plan" is displayed.

When airborne, "CONFIRM FLT PLN CHG" will be annunciated in the scratchpad; pressing the left LSK a second time will enter the point in the flight plan.

STEP 1: Press the FPLN Key

(1) Type in a Valid Coordinate format into SP. Waypoints can be entered in DDM or MGRS, for DMS use the high precision coordinate edit page.

(2) Depress the LSK next to the waypoint you want the new waypoint to precede, in this example the Flight plan is empty, so the new waypoint will be inserted as the active waypoint regardless if LSK1 or LSK2 is depressed.

💡 If the flight plan were not empty depressing LSK1 would insert the new waypoint as the active waypoint.

FPLN Page Insert a Waypoint

(1) Insert initial Waypoint into SP

(2) Press LSK of the waypoint you want the new waypoint to precede

(3) New waypoint added between AAA and BBB.

Bearing/Distance Vector Waypoint Calculator

A new waypoint which is a bearing/distance vector from an existing waypoint may be created in the scratchpad. This new waypoint may be inserted in the flight plan, if desired. The vector waypoint is calculated by entering the desired "bearing/ distance" in the scratchpad and pressing the LSK adjacent to the base waypoint of interest. The CDNU displays the coordinates (either Latitude/Longitude or MGRS) of the vector waypoint at the specified bearing and distance from the specified point in the scratchpad. This location may then be entered wherever desired, but it does not affect the original waypoint in the flight plan.

The bearing and distance are entered as a bearing, optionally followed by a "T" or "M" (True/Magnetic reference), followed by a "/", followed by distance, followed optionally by an "N" or "K" (nautical miles or kilometer reference). Bearings are entered as up to three digits, optionally followed by a decimal point and an additional digit. Distances are entered as up to four digits, optionally followed by a decimal point, and up to two additional digits. If the optional "T"/"M" or "N"/"K" are not entered, the bearing will default to Magnetic and English/Metric toggle state determines the distance format.

FPLN Insert with LANTIRN

The CDNU permits the creation of new waypoints via LANTIRN. Newly created waypoints will always be placed at the end of the Flight plan and be numbered 51 and up.

The naming convention for LTS Designated waypoint depends on the accuracy of the LTS designation. The naming scheme is as follows: Start name with "/LT"

• If a valid laser range is available at designation, add "*".
• If no laser range is available a dash is appended.
• If the LTS is GPS aided at the time of designation, add "*", if not GPS is not available a dash is appended.
• Add the GPS FOM.

For example, an LTS designated waypoint made with laser ranging and perfect GPS will be named: /LT**1.

Similarly, if the designation was made without laser ranging and with a GPS FOM of 4, the name will be /LT−*4.

If the LTS designation is established with valid laser ranging, GPS aiding, and a FOM of 1 (**1), then the displayed target altitude will be sent to the new waypoint file. If not **1, then the altitude for the new waypoint will be set to zero.

STEP 1: Depress the S-7 FOV hat on the LTS controller for more than 2 seconds

STEP 2: Scroll to end of flight plan

The newly created waypoint is inserted as waypoint 51 into the flight plan.

FPLN waypoint deletion

FPLN STEP 1: Press FPLN Key

(1) Type"-" (dash) into SP using keypad

(2) Press LSK of waypoint to be deleted

(3) Waypoint BBB deleted. Other waypoints move up in Flight Plan

Waypoint Edit Page 1/2

WP STEP 1: Press the FPLN Key

STEP 2: Press LSK left of desired waypoint

(1) Waypoint Name

(2) Special Waypoint designation, waypoint can be designated as one of 3 Priority waypoints or as one of 4 generic priority waypoints, additionally DEST can be selected to designated the waypoint as the DEST steering waypoint. And LTS can be selected to make the waypoint one of 20 LTS waypoints. Any waypoint designation can be saved by depressing the ENTER Key on the Opposite LSK.

(3) Waypoint coordinates. Format can be changed by depressing LSK 5. If coordinates need to be edited the modified coordinates are entered in the SP and inserted by depressing LSK 1

(4) Waypoint ID. Waypoint IDs can be set as desired. Multiple waypoints can have the same ID. Waypoint ID has no effect on waypoint position in the flight plan.

(5) Magnetic Heading to waypoint from current position.

(6) Waypoint coordinate format (DMM or DMS), also controls in which format waypoint coordinates are entered in the SP. MGRS is always enterable and does not need to be selected with LSK 5.

(7) ENT key updates the FMC and CDNU with the changes made to the waypoint.

(8) SP. Special waypoint designations are available. FP, ST, DP, HA, IP, HB are available to be associated with any waypoint. Only one waypoint can have a specific waypoint designation at a time. For example WP32 might be designated as Surface Target.

(9) Desired Airspeed to Waypoint.

(10) Priority Waypoint: Number P1-P7. DEST waypoint designation: only 1 waypoint at a time. LANTIRN Waypoint number: Up to 20 waypoints from a CDNU flight plan can be transferred to the LTS. The LANTIRN waypoints so transferred are numbered sequentially from 1 to 20.

Waypoint Edit Page 2/2

WP STEP 1: Press FPLN Key

STEP 2: Press LSK left of desired waypoints

STEP 3: Horizontal scroll to WPEDIT 2/2 page

(1) Waypoint ID and Name

(2) Range, Bearing, and ETA/ETE to waypoint via Direct.

(3) Range, Bearing, and ETA/ETE to waypoint via the Flight Plan.

(4) GGW Station Selection (toggles between 3/4/5/6). Designates station to which target information will be sent when LSK 7 is depressed.

(5) Waypoint Altitude.

(6) Estimated Time Enroute (ETE) or Estimated Time of Arrival (ETA) to waypoint.

(7) LSK6 toggles DIR/FPN time readouts (Items 16 and 17 below) between ETE and ETA formats.

(8) Depression of LSK 7 transfers Waypoint information to GGW station specified using LSK 3 as the new primary target. Aircrew should verify transfer using PTID JMSN page.

(9) Time of Arrival (TOA) Readout.

High Precision Waypoint Edit Page

STEP 1: Press the F3 Key

(1) Return to previous CDNU Display page

(2) Edit Longitude

(3) Edit Latitude

(4) Coordinate Format Selection (cycles between DMS/DMM)

Direct Steering

Direct to steering is available with:

A. Impromptu waypoints:

• Lat/Long
• UDL
• ICAO IBD
• Vector

B. Flight plan waypoints:

• Inserting via UDL
• Scrolling through DIR to page

The Direct steering page offers multiple ways to obtain steering to a horizontal position.

• Direct to a Flight Plan waypoint
• Direct to a History waypoint
• Direct to a User defined Label
• Direct to an ICAO waypoint
• Direct to an impromptu waypoint

Direct to steering can be initiated to the next flight plan waypoint or to any of the horizontal positions described above. It is also possible to bypass a number of future flight plan waypoints with the DIR steering function.

Impromptu waypoints may be inserted into the flight plan by entering the desired position into the scratchpad, then pressing LSK1 (adjacent to "Direct-To [ ]"). The impromptu point may also be defined as a vector from the present position of the aircraft by inserting a bearing and range in the scratchpad instead of a position. Vector waypoints are handled in exactly the same manner as a normal waypoint. In both cases, the impromptu waypoint is inserted prior to the current active waypoint, which becomes the first future waypoint.

It is possible to insert an impromptu waypoint and bypass a number of future flight plan waypoints. First depress the "DIR TO" key on the CDNU, then enter the impromptu waypoint into the scratchpad. Finally, press the LSK adjacent to the waypoint where the original flight plan is to be resumed. This makes the impromptu waypoint the active waypoint and the selected waypoint the second waypoint in the flightplan.

After selecting a waypoint for the Direct-To operation, the normal Flight Plan page display is returned, with the course, vertical angle, offset and advance displays restored as appropriate. Ability to edit the flight plan is restored. The computer-generated turn point is inserted as a standard latitude/longitude or MGRS waypoint in history as the most recently passed point. The use of the Direct-To function has no affect on waypoint sequencing (AUTO/OFLY/MAN).

DIRECT-TO a Flight Plan Waypoint

STEP 1: Press the DIR key

(1) "to" disappears when scrolled away from active waypoint.

(2) Active waypoint.

STEP 2: Vertical Scroll to desired waypoint and select with left LSK

(3) Scrolling down to the desired Direct-To-Waypoint (DDD) and pressing the associated LSK will make that waypoint the new active waypoint.

💡 All passed waypoints (In this case 01;02;03) pass into history. Any waypoints after the one DIR TO is selected remain in the flight plan as normal. The last 5 history waypoints can be recalled and steered DIR TO again.

RESULT

DDD is now the Active FPLN waypoint. All preceding FPLN waypoints have been passed into history.

(4) Direct-To turn point is computer generated to provide turn anticipation. Any next empty waypoint from 51 and up is chosen and passes into history once passed.

(5) DDD (Waypoint 4) is now the new active waypoint. On PTID that waypoint is displayed with the "Hot Dog" Symbol.

DIRECT-TO an Impromptu Vector Waypoint from present position

Direct STEP 1: Press the DIR key

(1) Enter desired vector into SP.

(2) New waypoint is entered as new EGI Fly To Point into flight plan.

(3) After new waypoint has been passed normal flight plan sequencing will continue.

The Vector is inserted as Lat Long into the flight plan.

Progress Page 1/3

STEP 1: Press the PROG Key

(1) Desired Track - corrected for aircraft present position MVAR.

(2) Active waypoint.

(3) Displays TO, FROM, DIST and TTG to and from active waypoint.

(4) Toggles Lines 4 and 5 between:

• TO-DIST
• FROM- DIST
• TO-RANGE
• FROM - RANGE

(5) Display cross track deviation (XTK) or track angle error (TKE).

(6) Displays:

• Ground Speed (GS)
• Ground Speed CMD (Gscmd)
• Ground Speed Error

(7) ETE to active waypoint.

(8) Aircraft drift (ground track related to heading right (R) or left (L)).

• Ground Speed (GS): Current ground speed
• Ground Speed Command (Gscmd): Ground speed necessary to achieve current planned time of arrival at active waypoint.
• Ground Speed Error (FAST/SLOW): Correction required to achieve current planned time of arrival at active waypoint.

Progress Page 2/3

Progress STEP 1: Press the PROG Key

STEP 2: Vertical Scroll to PROG 2/3 Page

(1) Descend Angle to maintain to arrive at next FPLN waypoint at desired altitude.

(2) Next FPLN waypoint altitude.

(3) SYNC function. Syncs maintain alt readout back to glidepath.

(4) Indicates required descend angle to intercept glideslope.

(5) Current Altitude MSL.

(6) Current Descend Rate in Feet Per Minute (FPM)

(7) Above or Below vertical path to next FPLN waypoint.

(8) Required Descend Angle.

Progress Page 3/3

STEP 1: Press PROG Key

STEP 2: Vertical Scroll to PROG 3/3 Page

(1) Integrated navigation solution of present position.

(2) Current ground track (Toggle Between Magnetic and True heading)

(3) Ground Speed (GS) readout and True Airspeed (TAS) from CSDC(R).

(4) CDNU calculated wind.

(5) Magnetic Variation.

MARK Page

STEP 1: Press the IDX key

STEP 2: Press LSK 6 (MARK Page)

(1) Mark position inserted in first slot.

(2) Time of Mark in Zulu time.

(3) Empty Mark position slot, mark position is inserted by depressing the MARK key on the CDNU keyboard and then depressing the LSK lef of the mark position slot to be filled.

Nine mark positions may be saved in nonvolatile memory and given a user defined label in the same manner as on the Flight Plan page. The Mark List page records the position of the mark and the associated time of the mark.

To save a point in the Mark List, press the "MARK" key when the aircraft is directly over the point to be marked. This action puts the position (latitude/longitude or MGRS coordinates) in the scratchpad.

Access the MARK page from the Index page and depress the LSK to the left of the position where the mark will be saved. The time of the mark will also be saved. Once a marked position is entered into the Mark List, pressing the LSK to the right of a position copies it to the scratchpad. A waypoint may be retrieved from the flight plan and copied into the Mark List.

First, use the vertical arrow keys (↑/↓) to scroll the Flt Pln page to the waypoint (active, history, or future) to be stored in the Mark List. Press the F7 key twice, entering COPY WHAT? into the scratchpad, then press the LSK to the left of the waypoint to be copied. This will enter the position (or user-defined label) in the scratchpad, as well as all available waypoint attributes (identifier, elevation, frequency, and declination). Go to the Mark List page and insert the waypoint normally.

RNAV INAV Page

STEP 1: Press the RNAV key

Integrated navigation solution Page (INAV)

(1) Current Position (High Precision) Integrated position from IMU and GPS.

(2) RIO Requested System Mode (start page).

(3) Coordinate format set for display on all navigation displays.

(4) FREEZE function. (Not Implemented).

(5) CSDC(R) Selected System Mode.

(6) Enters Navigation Update page.

RNAV GPS Page

STEP 1: Press RNAV key

STEP 2: Horizontal scroll until RNAV GPS Page

(1) Current Position (High Precision) as derived from the GPS.

(2) Deviation from integrated solution.

(3) Estimated Horizontal Error (EHE).

(4) Y-Code.

(5) Indicates deviation data is from integrated solution.

(6) Number of tracked satellites (SATS).

(7) GPS computed Altitude.

(8) Figure of Merit (FOM).

RNAV INS Page

STEP 2: Horizontal scroll until RNAV INS Page

(1) Current Position (High Precision) as derived from the INS.

(2) Deviation from integrated solution.

(3) Indicates deviation data is from integrated solution.

(4) INS Quality (Q) in NM per Hour.

(5) INS computed Altitude.

(6) Figure of Merit (FOM).

RNAV Blend Page

STEP 2: Horizontal scroll until RNAV Blend Page

(1) Current Position (High Precision) as derived from the Blended Solution.

(2) Deviation from integrated solution.

(3) Estimated Horizontal Error (EHE).

(4) Number of tracked satellites (SATS).

(5) Indicates deviation data is from integrated solution.

(6) INS Quality (Q) in NM per Hour.

(7) GPS computed Altitude.

(8) Figure of Merit (FOM).

STAT Page

STEP 1: Press the STAT key

The stat page displays the system status of the F-14B(U)s navigation equipment.

Holding Page

A holding pattern may be associated with one fixed waypoint in the flight plan, called the holding fix. When the aircraft crosses the holding fix, holding guidance is activated, suspending normal leg sequencing until the holding pattern is canceled. Three parameters define the holding pattern: Inbound Course, Turn Direction, and Pattern Length. The CDNU Hold page is accessed from the Index page. If no holding course is entered, then the flight plan inbound course will be used when holding guidance is activated.

Holding STEP 1: Press the IDX key

STEP 2: Press LSK 7 to access the HOLD page

When the holding fix is passed for the first time, holding guidance computations are activated. At that time several changes occur, both in flight plan operation and page displays:

1. Automatic leg sequencing is suspended.

2. Course edits on the Flight Plan page may no longer be made. Inbound holding course edit may be made on the Hold page.

3. All displays reference the inbound course displayed on the Hold page.

(1) Inbound Course. Insert 3 digit value in scratchpad and press LSK2.

(2) Toggles between left and right turn direction.

(3) Insert a 3 digit number in the scratchpad and press LSK4.

(4) Press apply once Hold point parameters are set.

(5) Hold point entry

(6) HOLD Symbol on FPLN page

Once the Hold Pattern has been entered, the course display and "to" indicator on the Flight Plan page are replaced with "Holding" and "at". The entry advisory display on display line 1 of the Hold page is changed to read "HOLD IS ACTIVE". Vertical angle display is automatically changed to "MAINTAIN" and selection of other vertical angles is prohibited.

If any holding pattern definition parameters are changed while in the pattern, the changes are applied after the aircraft passes the holding fix (transition from "TO" to "FROM"). When holding guidance has been activated, all course and lateral deviation displays now reference the inbound holding course, irrespective of whether the aircraft is on the inbound or outbound leg of the holding pattern. However, the ten second turn alert (Pilot VDIG-R Bezel and RIO DDI) will be computed on the outbound leg as though there is a phantom waypoint on the outbound leg where the turn inbound should be initiated.

Exiting a Holding Pattern

Holding STEP 1: Press IDX key

Holding STEP 2: Press LSK 7 to access the HOLD page

Holding patterns may be terminated in two ways:

1. Press LSK8 on the Hold page to cancel. In this case a leg switch to the next flight plan waypoint will occur when the fix is crossed again (if automatic flight plan advancing is selected).

2. The Direct-To function is activated to a future waypoint.

Intercept Page

Up to nine moving targets may be simultaneously defined. Intercept solutions to these targets may be used in two ways:

1. The intercept solution may be inserted as the active waypoint for immediate (i.e., Direct To) execution.
2. The intercept solution may be inserted as a future waypoint to implement a future rendezvous with a moving target.

Intercept STEP 1: Press the IDX key

STEP 2: Press LSK 8 to access the Intercept page

(1) Position of last target fix.

(2) Track of target. Toggles between Magnetic and True North.

(3) Time of last target fix.

(4) Bearing and distance to present target.

(5) Target ground speed.

(6) Moving target parameters have been entered and this intercept is selected for insertion into the flight plan.

Intercept Calculations

The Intercept 1/9a page is accessed from the Index page using LSK8. Subsequent pages (Intercept 2/9a and beyond) are reached by scrolling up or down until the desired page is visible. Current position, Ground Track, and Ground Speed is displayed or can be entered on the Intercept x/9a page (where "x" is the specific intercept number). Range and bearing to the intercept is also shown. Intercept x/9b page is accessed by using the left/right arrow keys to scroll from the Intercept x/9a page. The Intercept x/9b page displays the current Time to Intercept, point of closest approach if no intercept in possible, and the current true airspeed.

(1) Current Time to Intercept.

(2) Current true air speed.

(3) Can enter and display alternate true air speed.

(4) Alternate time to intercept based on alternate TAS.

(5) Moving target parameters have been entered and this intercept is selected for insertion into the flight plan.

A calculator function is provided to allow the RIO to enter an alternate true airspeed and see the effect on the time to intercept and point of closest approach miss distance. This calculator is available for all intercepts not inserted into the flight plan (based on Direct-To solution) and for the next intercept in the flight plan.

The CDNU calculates the true minimum time intercept to the moving waypoint. If intercept is not possible, a point of closest approach is computed. The calculations are based on a flat earth approximation about the equator. Therefore, the solution will slowly begin to degrade as the distance to the intercept point increases, and the intercept solution gets close to the poles.

Solutions are cyclically computed for all intercepts, whether inserted in the flight plan or not. If they are not inserted, the computations are performed as if they were Direct-To intercepts. Changes on the Intercept "a" page immediately affect the intercept solution in the flight plan.

Inserting Intercepts

An intercept can be inserted directly into the flight plan as the active waypoint by accessing the desired Intercept x/9a page and pressing LSK8 twice (confirmation is required). This calls up the Flt Pln page, and depressing the LSK next to the waypoint before which the intercept is desired enters it into the flight plan. When an intercept is the active waypoint, the intercept location is cyclically updated based on current aircraft position and speed, the moving target definition, and current wind. The intercept point location is adjusted, as required, and the inbound course is edited to match the current Direct-To course into the waypoint. When the intercept is inserted as a future waypoint, then the intercept location is updated based on the location of the flight plan waypoint immediately prior to the intercept, the distance along the flight plan to that waypoint, current aircraft speed, the moving target definition, and current wind. The estimated time of arrival at the waypoint immediately prior to the intercept is computed. Then the intercept point is computed from that point and time.

Intercept Passage

When an intercept is passed into history, the latitude/longitude of the intercept at the time of waypoint passage is recorded as the flight plan history waypoint. All parameters defining the moving target remain on the intercept page, but the intercept is removed from the flight plan.

Parallel Offsets

WIP

BDHI Steering Page

If EGI is selected on the TACAN command panel, then the RIO has four options: selecting the EGI fly−to point (default), selecting a flight plan waypoint, selecting the GGW/LTS next launch WP (TGT or LP), or synchronizing the BDHI with HUD steering.

STEP 1: Press the F4 Key

(1) Current Steering source waypoint location.

(2) Select Next Launch GGW Target Steering. (Currently selected Station with programmed Target).

(3) Select Next Launch GGW Launch Point Steering. (Currently selected Station with programmed Launch Point).

(4) Default the EGI Fly to WP is selected.

(5) Select a waypoint from the FPLN to receive BDHI steering to. (Separate from EGI Fly-To or DEST Steering Waypoint).

(6) Synchronizes BDHI with HUD/VDIGR steering source.

BDHI Steering to Page

BDHI STEP 1: Press LSK adjacent to FP WP on BDHI steering page.

Time Selection Page

STEP 1: Press the F6 Key

The CDNU has a Time Selection Page accessed via the CDNU F6 function key. The Time Selection menu allows the RIO to select the source for HUD/VDI Primary and Secondary TTG and ETA windows. The Primary TTG/ETA is present on both the HUD and VDI. To avoid cluttering the HUD, the Secondary TTG/ETA is present ONLY on the VDI and defaulted to OFF. If desired, the RIO must manually select the Secondary TTG/ETA to ON via the F6 page.

(1) Displayed on the CDNU page when TTG/ETA is turned OFF via LSK 1 or LSK 5.

(2) Time To Go and Estimated Time of Arrival for the HUD steering point.

(3) (BTG/BTA): Time To Go and Estimated Time of Arrival for the BDHI steering point.

(4) (RTG/RTA): Time To Go and Estimated Time of Arrival to a designated "Route To" waypoint.

(5) through (8) same but for secondary TTG and ETA.