LANTIRN

The LANTIRN (Low Altitude Navigation and Targeting Infrared for Night) system was originally developed as a combined navigation and targeting pod for the F-15E and F-16. When the U.S. Navy sought to expand the F-14 Tomcat's air-to-ground capability, Martin Marietta (now Lockheed Martin) adapted the targeting pod for integration with the aircraft. The navigation pod was omitted, leaving only the targeting pod in service with the F-14.

On early F-14 implementations, the aircraft lacked the required MIL-STD-1553 data bus for full integration. The LANTIRN pod therefore operated as a largely self-contained system.

The F-14B Upgrade introduces full integration between the aircraft and the LANTIRN pod. The pod now communicates directly with aircraft systems, allowing the VDIGR to display the LANTIRN line of sight in all operating modes. Integration with the AWG-9 radar also enables the pod to automatically slave to the radar line of sight.

The LANTIRN control panel (LCP) is retained in the F-14B Upgrade, TCS Video Feed or LTS video feed can still be toggled via the LCP TCS/LTS video switch. TCS or LANTIRN video feeds can also be selected through the ECMD video Menu.

The LANTIRN FLIR sensor provides three selectable fields of view. The Wide field of view covers 5.9° and supports a maximum slew rate of 8.5° per second. The Narrow field of view covers 1.7° with a maximum slew rate of 1.8° per second. The Expanded field of view provides a 0.8° digital zoom of the Narrow field of view, reducing image resolution while limiting maximum slew rate to 0.7° per second.

A/A Mode

Integration with the AWG-9 radar enables the pod to automatically slave to the radar line of sight during air-to-air when QADL is selected and the radar is in STT. The RIO can command a LANTIRN point track to continue tracking the target independently, even if the STT track is lost. If point track is subsequently lost, the pod automatically returns to QADL.

A/G Mode

In A/G mode the LANTIRN operates in 3 Basic Tracking modes:

Area Track

Area track enables the LTS to track a fixed Infrared (IR) scene if the scene contains some temperature variations or thermal texture. The LTS enters area track when commanded by the RIO or when the system defaults from point track. Once selected, an AREA status indication appears on the RIO PTID LTS display. If area track is selected but lock-on is unobtainable, the LTS defaults to computed rates track.

Computed Rates Track

Computed rates track provides interim line of sight (LOS) control during the transition from one LOS control scheme to another, or whenever track is temporarily broken. The computed rates track logic calculates the current position of the target from previous target motion data to maintain target tracking until the ensuing function takes control of the LTS LOS. The LTS defaults to the computed rates track function if other tracking modes cannot be entered or maintained.

Point Track

Point track enables the LTS line of sight (LOS) to track a hot spot such as a tank or vehicle. The LTS enters point track when selected by the RIO. Once selected, a POINT status indication appears on the PTID LTS display. If point track is selected but lock-on cannot be obtained or maintained (e.g., the target is too close and has too little thermal detail to point track), the LTS defaults to area track mode, except A-A mode in which case the LTS transitions to computed rates mode.

Q (Cue) Modes

• Q Waypoint: With Q waypoint any of 20 LTS designated waypoints can be toggled to. (See Waypoint list explanation below).

• Q GGW Target: GPS Guided Weapon Targets Stored in the Mission Data Processor can be cued by the LTS, these targets are stored separately from the overall 20 waypoint list.

• Q HUD: slaves the LTS LOS to the HUD.

• Q SNOWPLOW: slaves the sensor to the ground 15 NM directly in front of the aircraft along own aircraft heading. QADL and QHUD slave the sensor to either ADL (in A/A) or the aircraft wings symbol on the HUD (in A/G).

• Q DES: slaves the LTS back to the last obtained designation.

• Q Bullseye: slaves the LTS to the Bullseye Designated waypoint.

Waypoint List

The LANTIRN Pod can access a list of 20 waypoints designated either during pre flight planning or via the CDNU. Additionally any newly created LTS waypoint is stored in the LTS waypoint list. The LTS waypoint list is modified via the WP Edit 2/2 page. LTS waypoints are marked by a small L posted on the NVD PLT and NVD WP pages.

Coordinate formats

The CDNU RNAV page lets the RIO toggle between DMS, DMM and MGRS coordinate formats for display on the LTS display.

LTS Designated Waypoints

The RIO may create a new CDNU flight plan waypoint directly from a LANTIRN target designation. After establishing a valid LANTIRN target designation, holding the S-7 switch on the LANTIRN Control Panel (LCP) for at least 2 seconds stores the designated target coordinates (latitude/longitude) and GPS Figure of Merit (FOM) as a new waypoint in the active flight plan. New LTS-generated waypoints are assigned the next available waypoint number beginning with Waypoint 51.

If fewer than 20 waypoints in the flight plan are designated as LANTIRN (LTS) waypoints, the new waypoint is automatically assigned the LTS designation and is identified by an "L" in the upper-right corner of the waypoint number on the PTID NVD page. If 20 LTS-designated waypoints already exist, the waypoint is still created but is not assigned the LTS designation.

The waypoint name is automatically generated to indicate the quality of the target designation using the following format:

/LT[Laser][GPS][FOM]

Where:

• The first character is:

  • "*" – Valid laser range available at designation.
  • "-" – No valid laser range available.

• The second character is:

  • "*" – GPS aiding available at designation.
  • "-" – GPS aiding unavailable.

• The final digit is the GPS Figure of Merit (FOM).

Examples:

• "/LT**1" – Valid laser range, GPS aiding available, FOM 1.
• "/LT-*4" – No laser range, GPS aiding available, FOM 4.

When the designation is made with both valid laser ranging and GPS aiding, and the GPS Figure of Merit is 1 ("/LT**1"), the target altitude displayed by the LANTIRN is transferred to the waypoint. If these conditions are not met, the waypoint altitude is set to 0 feet.

Holding the S-7 switch for more than two seconds always creates a new waypoint. If valid target coordinates are not currently displayed on the FLIR, such as when operating in QHUD mode, the last available target coordinates are stored instead. Likewise, if the LANTIRN is cued to a GPS-Guided Weapon (GGW) target or an existing waypoint, those displayed coordinates are copied into the new waypoint.

If the LANTIRN calculates a negative Height Above Ellipsoid (HAE) during waypoint creation, an incorrect altitude may be transferred to the CDNU. In this case, the RIO must manually correct the waypoint altitude using the CDNU after the transfer is complete.

LANTIRN North Cue

During close air support (CAS) or Forward Air Controller Airborne FAC(A) missions it is crucial for the aircrew to know where north is based on where the LTS is looking. As such with the F-14B(U) software tapes an LTS north indicator was introduced. The circle represents a simplified rotating compass the square always points to where north is. So if for example the square is left of the circle, then the LANTIRN pod is facing eastwards.

LANTIRN Line Of Sight Cue

The LANTIRN Line of Sight Cue is presented in the VDIG-R when the RIO has LTS selected on the LCP. It replaces the TCS cue in both A/A and A/G when selected. If LANTIRN is in a non tracking mode an "N" is presented at the bottom of the triangle. The tracking modes are AREA Track and POINT track. In all other modes or Q modes an N is posted in the triangle. When the LTS cue is outside the HUD field of view it becomes dashed. In A/A with LANTIRN slewed to the radar LOS in STT the LTS LOS cue points along the radar LOS.

LANTIRN Video Elements

(1) Own Aircraft positional data:

• Position
• Altitude
• Groundspeed
• Pitch Angle

(2):

• WHOT (White Hot) or BHOT (Black Hot)
• AGC (Automatic Gain Control) or
• MGC (Manual Gain Control)

(3) Pod Information

• SRA: slant range
• AZ and EL is pod line of
  sight azimuth and elevation
  relative aircraft ADL
• UTC Time
• IBIT Codes

(4):

• A/G Mode or A/A Mode
• Rates Track (RATES)
• Area Track (AREA)
• Point Track (POINT)
• LASER CODE
• Weapon Type

(5):

• Target Information Q (Current Slew Point) (Except for QSNO, QADL, QHUD)
• Time to go until on top of the Currently selected Q
• Bearing and Range to Q
• Elevation to Q
• Location of Q (Only Displayed if a Location Q is selected)

(6) Attack Information:

• Stores Status and Time To Impact Indicators. (S6XXX) (S3RDY)
• Vertical line is the bomb release cue.
• The bomb release cue, is only shown if the selected Q is QDES and shows a vertical line along which a release cue travels downwards.
• TREL (Time to Release) changes to
• TIMP (Time to Impact) after bomb release

(7) North Indicator.

(8) LTS Reticle.

(9) Attack Information:

• Steering guidance towards the selected Q.
• Top line is deviation from heading (L/R Degrees)

LANTIRN Display on PTID

The LANTIRN pod feed is displayed on PTID via depressing the TCS switch in front of the HCU. With the video feed enabled TCS and LTS feeds can be toggled via the LANTIRN control panel or the ECMD video Menu.

Once the TCS or LANTIRN feeds are displayed on PTID they are overlaid with the PTID symbology. To disable the PTID symbology depress Pushbutton 7 OL on the PTID Menu.

For a complete discussion of LANTIRN modes and controls refer to the LANTIRN Chapter in the F-14A/B manual.