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How to Quickly and Effectively Locate and LockAir-to-Air, Beyond Visual Range - Threats

Using the AN/APG-68By

TreeHugger 388th VFW(Stephen R. Dines)

Introduction

The objective of this short course is to teach virtual air combat pilotsof the 388

thVFW how to quickly and effectively locate and lock up air-to-

air targets that are beyond visual range (BVR). To accomplish thisobjective, the content of this course will include basics of the Falconsfire control radar system (AN/APG-68) operation. Actual air-to-air radarstrategies used by members of the 388

thVFW and real F-16 pilots will also

be presented.

You are reminded that information presented in this course is intendedsolely for members of the 388

thVFW and cannot be distributed outside the

wing without the written authorization of the 388thVFW command staff.

Definitions and Important Radar Controls

The AN/APG-68 in air-to-air mode (all references made to the radar inthis course are in reference to air-to-air mode) sweeps an area ofcoverage that is based on three elements: azimuth, elevation, and rangeof the scan. Azimuth refers to how far left and right the radar covers(in degrees, 10, 30, or 60). Azimuth settings are changed by selectingthe OSB-18 button on the MFD using the mouse or pressing the F-8 key onthe keyboard.

Elevation refers how far up and down the radar scans. Elevation isscanned in bars up to a maximum of four. Since the AN/APG-68s radarbeam is narrow, the radar must scan separate bars to cover large areas.The available bar scan settings are dependant on the radar master modebut can include Bar One, Bar Two and Bar four. Elevation can be changedby selecting the OSB-17 button on the MFD using the mouse, or pressingthe shift and F-8 keys on the keyboard.

The number of degrees of azimuth and elevation together determine the

maximum search pattern of the radar or search area. Targets thatexist outside of the maximum search area are sometimes referred to asoutside the gimbal limits.

Radar Range, on the other hand, refers to the distance the radarsees from the nose of the jet in nautical miles (nm). The greaterthe range or distance, the more search area presented on the MFD. Theradar range can be changed by moving the radar acquisition cursor up ordown or by pressing the OSB-19 and the OSB-20 buttons on the MFD using


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388thVFW Training Document:

How to Quickly and Effectively Locate and Lock Air-to-Air BVR Threats

2D:\Download\A-toA Radar.doc

the mouse. It can also be changed by pressing the F-3 and F-4 keys onthe keyboard to decrease or increase the range, respectively.

The best advice from pilots of the 388thVFW is to map the above mentioned

radar controls to your joystick or Hands on Throttle and Stick (HOTAS).This practice can enable quick changes to radar settings without thepilot having to refer to the keyboard. This will help you to maintainsituational awareness, especially during combat Within Visual Range (WVR)as discussed in the section on ACM below. At a minimum, you should planto map the following radar commands to your HOTAS system:

Cycle air-to-air modes

Radar Cursor Up, Down, Left and Right

Lock Target on Nose

Cycle Air-to-Air Hardpoints

Radar Standby

Tilt Radar Up and Down Designate Target

Radar Range

Each joystick is different, but you should plan to map the Radar CursorControls, Tilt Radar, and the Radar Range controls to the throttle stick.Cycle Air-to-Air and Lock Target on Nose should be mapped to the flightstick. The remaining controls can be mapped to meet your personalpreference. Brief descriptions of these controls and additionalrecommendations for proper mapping to a HOTAS system are presented thesections that follow.

Radar Coverage, Modes, and Settings

The fundamental thing to remember about radar coverage is it depends onthree settings: azimuth, elevation, and range. The higher the settingsthe more coverage you obtain and the longer it takes the radar tocomplete scanning the volume of airspace. Therefore, if you want toreduce the time it takes to acquire a target, you must become familiarwith how the various radar settings affect radar coverage. Once youlearn this, you can use the different settings to help you buy timeto gain a tactical advantage against your adversary. The various radarmodes (i.e., Range While Search (RWS), Track While Scan (TWS), Air CombatMode (ACM) and Velocity Search (VS)) can also have a impact on radarcoverage, but are more specific to certain tactical situations as will be

discussed later.

What is the best mode and setting for acquiring a target quickly? Theproper radar mode and settings will depend on your current tacticalsituation. The sections that follow are intended to illustrate somebasic tips on the appropriate modes and settings for various tacticalsituations that you may find yourself in during Falcon4 adventures.


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The following two examples illustrate appropriate use of the AN/AGP-68sRange While Search Mode (RWS) air-to-air radar.

RWS

In this first example, suppose you have just taken off and are heading toyour next steerpoint. After a quick check of your radar, Threat WarningSystem (TWS), and a call into AWACs, you determine the picture isclear. Under these conditions, you may want to leave the radar in RWS,which is the F-16 pilots primary search mode for radar lookout andtarget detection. Pilots from the 388

thVFW and real F-16 pilots

recommend using this mode for searching since RWS mode has the largestazimuth sweep (60 left and right for a whopping total of 120 ofhorizontal coverage off the nose of your jet!). Therefore, if you arelooking for the best coverage RWS is the mode of choice. The defaultradar settings in RWS mode are azimuth=60, Elevation=4 bars, andrange=80 nm. I usually set the range at 40 nm. That way, I am not

broadcasting my presence to everyone on the planet. However, I mayperiodically change the range to 80 nm or 160 nm to check the airspaceover the target area or steerpoint. This practice can give me some last-minute data that I can use to change my ingress to the target, ifnecessary. Once I am done looking over a given area, however, I willchange the range setting back to 40 nm. This practice is reportedlyconsistent with other virtual pilots of the 388

thVFW.

If, however, you are getting "spiked by an inbound bandit or maybe youjust received a threat warning from AWACS or from another flight element,you will want to adjust the azimuth, elevation and range of your radaraccordingly to locate the threat quickly. The next example illustrates asituation where changing these radar settings may be appropriate.

Remember, the sooner you can acquire an inbound threat, the better yourchances of gaining a tactical advantage and surviving the encounter.

In our second example, suppose you are flying at your planned altitudeand heading when you receive information that an inbound bandit is offyour nose at 45 nm, 30 degrees-right, and at angels 25. In thissituation, you can narrow the radar search a bit to find the contact morequickly. From the RWS radar default mode (azimuth=60, Elevation=4 bars,and range=80nm), you might change your azimuth to 30 and reduce theelevation scan to 2 bars. If you still cannot see the bandit, youmay need to tilt the radar antenna to make certain that you are scanningthe proper altitude off your nose. Knowing how much to tilt your radarwill require that you interpret information from the radar acquisitioncursor on the MFD radar picture. Tilting the radar and using the radaracquisition cursor will be discussed in the next section.

Figures 1a and 1b below show how the radar display changes slightly after

Azimuth is 60 or A=6


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new settings for elevation and azimuth are made. As you can see from thefigures, the azimuth gates changed size as the azimuth setting waschanged from 60 to 30 and the displayed number near OSB 18 on the radardisplay changed from six (6) to three (3).

Figure 1aPlease note that the azimuth scan bars do not appear on the scope whenthe azimuth is set at 60. This is because they would lie outside thefield of view on the radar picture. Likewise, the elevation numberdisplayed next to OSB-17 on the radar display changed from four (4) to

two (2).

Figure 1-b

Let us now look at what happens when we tilt the radar.

Radar Tilting

Figure 2 below shows the radar picture in RWS default mode just aftertakeoff. Note the position of the radar acquisition cursor. It is nearthe lower right of the left MFD and is comprised of two small verticallines with two numbers adjacent and two the right of these verticallines. The top number shows the upper altitude of the total scan (i.e.,1-bar, 2-bar or 4-bar) and the lower altitude is represented by thenumber on the bottom.

In our example, the lower altitude of the scan is 13,000 feet and theupper altitude of the scan is 18,000 feet as shown in Figure 2. What

these elevation numbers reveal is the total elevation of the scan infeet. Another way to think of this is that we have bracketed adiscrete elevation interval (5,000 feet) within our current scan. Undermost circumstances, we should be able to see a radar return or contactthat is within range and within this elevation interval.

You should be able to use the upper and lower elevation numbers next tothe target acquisition cursor to help you quickly decide whether yourcurrent radar settings are going to enable you to see a potential threat,

Elevation is set at Bar-4

Azimuth is set at 30 or A=3

Note the Azimuth gatesnarrowed to represent 30 ofhorizontal scan in either

Elevation set to Bar-2,B=2


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especially if you have a bullseye on a high-aspect bandit. If you knowthe threats altitude, you

Figure 2: Radar Tilting

can quickly determine from viewing the elevation numbers on the radaracquisition cursor whether you have properly bracketed him.

To illustrate how to effectively tilt your radar, please consider thefollowing example. Suppose you receive a bullseye call on a threat, thatis 35 nm, 30 left of your nose and at angels 20. If you are at angels

15 in RWS mode, you may want to narrow the azimuth to 30 and set the barscan at two (2). In order to acquire the threat quickly, you will needto adjust the tilt on the radar to bracket an altitude of 20,000 feet ata range of 40 nm. If you fail to do this, you may not see the threat.

If you do not see the threat with these radar settings, you may tryreducing the azimuth setting to 10 and drop the bar scan to one (1) andtilt the radar accordingly to bracket the correct elevation to see theinbound threat. This will put your air-to-air radar in spotlightmode and will enable you to burn through his jammers or electroniccountermeasures, if he has them on. It is reported by some members ofthe 388

thVFW that in this mode you can see bandits 80 nm off your nose!

If you have tried to narrow your search but still cannot locate thethreat, you have a several options:1) Keep trying the methods discussed in the previous two paragraphs, 2)

Open up the search byusing the default settings for azimuth and elevation, and as a lastresort, 3) Check your six!

Remember, radar tilt is controlled by the F5 and F7 keys on the keyboard.As suggested in the previous section, you should plan to map these

Radar Acquisition Cursor. The upper

number is 18 and the lower number is13, representing he elevation range of


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important commands to your HOTAS. For my setup, I have mapped thesecommands to a two-way button on my throttle control stick. Mapping theimportant commands is important so take the time to plan out yourindividual configuration you will be glad you did when the heat of

virtual combat starts to rise.


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Other Radar Modes and Some Rules of Thumb

All of the examples presented thus far involved the AN/APG-68 air-to-airradar in RWS mode. What about the other radar modes available in the

Falcon4 world such as TWS, ACM and VS? The remaining BVR range radarmodes are TWS and VS. VS will not be discussed because it is seldom usedby F-16 pilots since it provides information on the closure rate oftargets only and does not provide enough information on a threat to beparticularly useful. TWS, however, is a very useful and important modeand will be discussed next. ACM mode is beyond the scope of this course,but will be discussed briefly after TWS.

TWS

TWS master mode is used primarily to track multiple targets at one time.It is the best mode for determining the number of contacts that arewithin range of the radar. TWS also provides data on heading, relative

airspeed, and can enable you to track up to 16 targets at once. Thelimit of TWS is that it can only sweep an azimuth of only 25 in eitherdirection off the nose of your jet at 3-bars and only 10 at 4-bars.Therefore, TWS is not the primary choice for searching airspace by manyvirtual pilots or real F-16 pilots. TWS is usually called up afterthreats have been located using RWS. However, some members of the 388

th

VFW use this mode as their primary search mode with great success. Whenmight you use TWS? To answer this question, consider the followingexample.

In this example, suppose you are inbound on a ground target approximately90 nm off the nose of your jet and that you are at angles 20 with theAN/AGP-68 radar in default mode (RWS: azimuth of 60, 4-bar scan, and

range 80 nm). In this example, your jet is loaded with a full complementof CBU-87s (a very effective cluster bomb against light and mediumarmored vehicles, troops, and light buildings) and four AIM-120s (I willassume you know what the 120s are for!). Before you reach the initialpoint, which is the steerpoint before you reach the target, it is goodpractice to check the airspace over the target area so that you can makelast-minute changes to the ingress if the situation warrants. To dothis, you would adjust the radar range setting accordingly to include thetarget area.

Before we continue with this example, it is recommended that you use theHorizontal Situation Display (HSD) in conjunction with the radar displayand note the position of the radar acquisition cursor in relation to theground target area. Figure 3 illustrates a cockpit view showing theradar picture and HSD for the tactical situation given in this example.


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Figure 3

As can be seen from the Figure 3, the HSD provides the pilot with anexcellent reference on the route of your current flight, ground targetlocation, and threat position relative the target area. As you move theradar acquisition cursor on your radar display, the same cursor on theHSD mimics your inputs showing you a birds eye view of where yourradar is looking. This turns out to be very useful for a couple ofimportant reasons. First, using both MFDs in this way can help you gainsituational awareness regarding your position relative to the groundtarget and any airborne threats within range of your radar. Secondly,this method can also help you to decide if a change in ingress to the

target area is warranted (you want to avoid jettisoning the CBU-87sunnecessarily!).

With the radars range set at 160 nm, it is now possible to check theairspace over the target area since our ground target is roughly 90 nmoff the nose of our jet. By using the radar picture and HSD together asdiscussed above, it will be possible to view any threats in relation tothe target area. Now that we have a better understanding of how to usethe radar picture and HSD together to improve our situational awareness,let us now return to our example.

Suppose that after approximately 45 seconds into the search you receive aradar contact somewhere near the target area. In RWS mode, you may beable to determine the contacts heading based on target histories but atthat range, it may not be possible. Furthermore, you may not be able todetermine the number of threats that make up that particular radarcontact either. Since RWS does not lend itself well to differentiatingbetween targets in close formation, especially at approximately 90 nm, itmay be a good time to switch radar modes. Before you do this, if youplace your radar acquisition cursor over the radar contact at this point,you can get a fix on the bullseye of the contact. With a quick note ofthis information, you are now ready to switch to TWS mode.

RadarAcquisitionCursors

Target Area


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Once you switch to TWS mode, you can use the bullseye information andchange the radar settings in TWS to quickly reacquire the target exactlyhow we did this in RWS mode. In our present example, we just obtained

the bullseye information on the contacts and can now narrow the azimuthand elevation a bit to locate the target quickly if necessary. The TWSdefault radar picture is shown on Figure 4.

Figure 4: TWS in Default Note position of radar contact in relation tothe target area.

As you can see from Figure 4, the TWS radar mode provides a better viewof the number of targets, their relative airspeed, and direction orheading. To lock up these targets, you would simply place the radaracquisition cursor over the target and designate it by pressing the

appropriate button on you joystick setup or by pressing the 0 key onthe numeric pad on your keyboard. Remember that if you lock up a threat,you will sound off his TWS and alert him of your presence. You may notwant to do this until he has a high aspect or you are confident that youcan take him out without disrupting your time over the target.

Let us now take a brief look at what we can do to quickly and effectivelylocate and lock targets that are WVR.

ACM

The primary purpose of ACM master mode is to point your weapons atthreats WVR. At this range (usually within 15 nm), you will not havetime to fiddle with the radar settings to attempt to locate a targetsince he will be working to get into position on your six oclock or toget you into his weapons parameters. Since the objective of this courseis to quickly acquire targets beyond visual range, it is not within thescope of this course to discuss ACM target acquisition. We can mention,however, that the best strategy for acquiring targets quickly using ACMis to map the following radar commands to your HOTAS so that you are notstruggling to find the right key on the keyboard, especially when you may


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be short on time. At a minimum, the following commands should be mappedto your joystick.

Cycle Air-to-Air Modes

Cycle Air-to-Air Submodes Lock Target on Nose

Lock Next Target

The Cycle Air-to-Air Modes and Cycle Air-to-Air Submodes will enable youto cycle through all of the AN/AGP-68 master modes and submodes quicklyby just pressing a button on your joystick. This will help you to avoidlooking away from the screen and risk loosing situational awareness.Lock Target on the Nose will help you to quickly lock the target rightout in front of you without waiting on the radar to complete the scan.This can be a lifesaver in a head-to-head situation. Lock Next Targetcan be used to lock the next target within the view of the HUD.

A complete description of all of the ACM submodes can be found in theFalcon 4.0 instruction manual.

Closing Comments

What is the most important thing to remember when trying to quicklylocate and lock air-to-air BVR threats? Map the important radarcommands to your HOTAS system to start. Once you have done that,practice adjusting the radar settings and tilting your radar to paintyour contact quickly. When you become proficient at making changes toyour radar modes and settings quickly by using the bottons on your HOTASsystem, you can focus the majority of your attention on maintaining

situational awareness and planning a strategy to gain a tacticaladvantage at the merge, if it comes down to that!

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