The APG-73 is an all-weather, coherent, multimode, multiwaveform search-and-track sensor that uses programmable digital processors to provide the features and flexibility needed for both air-to-air and air-to-surface missions. It is an upgrade of the APG-65 that provides higher throughputs, greater memory capacity, improved reliability, and easier maintenance without associated increases in size or weight.

Phase II of the APG upgrade completed development. It incorporates a motion sensing subsystem with reconnaissance software, a stretch waveform generator module, and a special test equipment instrumentation and reconnaissance module. With these enhancements, the F/A-18 aircraft will have the hardware capability to make high resolution radar ground maps comparable with those of the F-15E and the U-2 aircraft, and be able to perform precision strike missions using advanced image correlation algorithms.

The APG-73 pulse doppler radar capabilities enable the detection of targets against ground clutter, which in turn makes it possible to engage targets flying at low altitudes below the radar carrying aircraft. The processing capabilities of the APG-73 are many times superior to its predecessor, the APG-65. The APG-73 is capable of the simultaneous tracking of several targets, in this way enabling simultaneous multi-target engagement with the active AIM-120 radar-guided missile.

If you can't make it to the target area undetected , perhaps the length of your mission requires you to fly at a higher altitude lo conserve fuel , your next best strategy is taking out the air opposition with a single pass, before they have a chance to lure you into a dogfight. Doing this requires great skill and a thorough command of your air-to-air targeting weapons and engagement systems. It also requires cooperation with your wingman and intelligent leadership of your flight rarely will you face just a single bandit.

Any successful engagement begins with finding the enemy. Most preferably finding him (even a split second) before he finds you. Letting him catch you unawares could mean your untimely demise. With the advent of longer-range missiles, air combat moved from close-range visually guided combat to the engagement of targets that were beyond visual range (BVE). Systems that could detect and/or acquire BVR targets were invented, and the skillful use of these systems (such as radar and radar warning receivers) became the deciding factor in modern missile combat. These detection skills are discussed in this section.

The APG-73 Radar is a coherent, X-band, multiple PRF, multi-mode attack radar with sophisticated electronic counter-countermeasure features. It provides rapid acquisition of short-range targets and has an excellent capability against long-range, high closing rate targets.

One of the the first concepts you must understand to effectively use your radar is how to control your radar antenna. The antenna is an electrically powered device located in the nose of your aircraft, scanning both back and forth and up and down. A maximum of 70° is scanned to either side, so obviously the radar cannot see targets located behind you. The antenna can also scan vertically in set steps known as "bars"; the radar scans across one bar, moves up several degrees, and then scans the next bar in the opposite direction. Finally, the center point of the scan is adjusted up and down to a maximum if ±60°. Again, this means that your radar cannot see targets directly above or below you because they are outside of the antenna's scan area.

Where does time fit into all this? It's simple, really. The antenna is scanned at a set speed, which is optimized to provide the best target detection under all circumstances. Since the antenna scan rate speed is fixed, seining a large- area takes longer than scanning a small area. Scanning a smaller area also provides faster updates on any targets detected in that area than would a larger scan. Things can happen quickly in air-to-air combat, and you always want to balance how much are you are scanning against how quickly the greatest threat are closing on your aircraft.

In Jane's F/A-18 antenna side to side, or azimuth, scan setting is usually controlled by MDI PB19. Some A/A radar sub-modes have azimuth scans that are fixed and not adjustable. For those A/A sub-modes that allow the elevation bar setting to be changed, this is located on PB 6. The elevation scan angle is important to consider as well. By default, the radar scan is centered on the horizon and stabilized so that aircraft climbs or dives keeping the antenna scanning back and forth along the horizon. This works great for detecting targets that are close to your altitude, but targets that are greatly above or below your altitude might fall outside your scan and be missed. In this case you might want to adjust your antenna up or down a degree or two. A couple of degrees may not sound like much, but as range increases it can have a dramatic difference on what you see or don't see on your display.

The choice of PRF is perhaps the most critical parameter any real life radar designer must deal with. All other conditions remaining the same, the PRF choice determents how well the radar can measure range and closing velocity us well as how well it can reject ground clutter. There are three generally accepted categories of radar PRF; Low, Medium, and High. UnfortunateIy, there is no one magic solution among these three, as each has it's own strengths and weaknesses, as summarized below.

The APG-73 radar in the Super Hornet uses medium and High PRF's. Interleaved PRF is also available in some sub-modes, and what this means is that for one antenna scan the radar uses Medium PRF, and as it scan back the other way it uses High PRF. This interleaving of PRF provides the best compromise in most situations.

You may have noticed that High PRF has problems with low closing rate targets. This is because High PRF uses Doppler frequency shift to sort targets out of the received radar return. The less closure there is between the target and your aircraft, the smaller the target return is, and, after a certain point, a target may be lost from your display. For this reason, a MPRF setting may he a better choice when facing targets that are not at long range.

You can also use the effects of Doppler to your advantage. By turning perpendicular to a threat radar system, you minimize the amount of Doppler shift they can see, and you just might be able lo break a lock. Using chaff in this situation can further help you break lock, as the threat radar has a much harder time rejecting chaff when there is little or no Doppler shift. However, don't be surprised if an enemy Ace tries the same tactic on you.

An aircraft's Radar Cross Section (RCS) is a value used to express how well that aircraft reflects energy back to the radar. The important parameler here is not so much size as it is shape and material composizion. Some materials reflect radar energy' very well, while other, tend to absorb it. The shape is important in determining exactly what direction the maximum amount of reflected energy travels in. So called "stealthy" aircraft use a combination of materials and shaping to minimize the amount of radar energy they reflect at certain angles.

Your F/A-18E Super Hornet has a degree of "stealthiness," or most correctly "signature reduction" incorporated into its basic design. Compared to the F/A-18C Hornet, the Super Hornet's engines are almost totally buried within the airframe. Another obvious feature contributing to stealth is the "sawtooth" shape of the landing gear doors. Other less obvious treatments include various coatings and materials desired to minimize the aircraft's radar signature as much as possible. Just as the shape of the aircraft varies between the front and sides, so does the radar cross section. In general, most aircraft have a larger cross section to the top, bottom, and sides than to the front or rear. Because of this, targets may be detected sooner or later based upon their aspect to you, particularly if you are using a Medium PRF setting.

Electronic countermeasures (ECM) are typically used to defeat or at least degrade the ability of radar systems to track or lock on to a target. In the real world, ECM is as much an art as it is a science. There are three main categories of ECM that arc used in Jane's F/A-18. These three categories are Noise Jamming, Gate Stealers, and Decoys.

Noise jamming raises the level of the background against which target returns must be detected, thus swamping out all but very strong returns. However, the jammer also serves as a beacon, revealing both the presence and the direction of the jamming aircraft. The purpose of noise jamming is to deny the radar being jammed the target range and closing rate. Most modern radar systems cope with this type of jamming by reducing the receiver sensitivity (and thus lowering detection range) while also providing an azimuth to the jamming aircraft.

In Jane's F/A-18, noise jammers are either stand off jammer or internal self-protection jammers. Standoff Jammers (such as EA-6B aircraft carry) are large, powerful systems that attempt to degrade the effectiveness of all radar systems within a certain area and along a certain bearing. Self-protection jamming systems (such as your ASPJ) arc typically used by fighter or attack aircraft to mask themselves against a single specific threat radar. The primary difference between the two types is that the standoff jamming system is much more powerful and can affect many radar systems along a specific axis, thus potentially masking multiple aircraft from detection. The self-protection noise jamming system can only protect the aircraft that it is mounted on, and because it has lower power, it has less effective range. Once a radar gets close enough to a target masked by jamming, it can "burn through" the jamming and once again detect the target normally.

Whereas noise-jamming systems affect mostly search and TWS radar sub-modes, the gate stealer jamming system only affects STT. A gate stealer is used to prevent a radar from usefully tracking the target. In essence, the stealer disrupts radar tracing by transmitting false target returns contrived to capture the "gate" which the radar places around the aircraft's skin return for clutter reduction and tracking. Once the "gate" is captured, the stealer "walks" the return away from the actual aircraft track and then breaks the lock by transferring the "gate" to clutter.

There are two types of radar decoys in Jane's F/A-18. The simplest is Chaff, which represents bundles of metal-coated dielectric fibbers. When released, they can hang in the air for long periods of time and create a sizable radar return. Upon being dispensed, the chaff rapidly decelerates and except for atmospheric effects, soon have little motion. Thus most modern radar systems can quickly reject the chaff echoes as false targets. If dispensed in conjunction with evasive maneuvering, chaff can break the radar's lock on the aircraft.

The second type of decoy in Jane's F/A-18 is the TALD or Tactical Air Launched Decoy. This device really a small glider, is released from the aircraft similar to a weapon and mimics a real aircraft's RCS and flight profile. Its primary use is to trick enemy ground-based radar operators into illuminating the TALD and thus pinpointing their location for SEAD aircraft to attack.

Properly identifying your target is vital to ensure you are engaging an enemy and not a friendly aircraft in the heat of battle. Targets may be identified visually, in conjunction with a friendly air traffic controller, through your aircraft's Identification, Friend or Foe (IFF) system, or using your radar systems NCTR function.

Visual detection is pretty self-explanatory. Using your Mark One eyeballs, you determine what your target is by the type of aircraft and the markings on that aircraft. The main disadvantages to this method is obvious; you need to get close, and during the night or bad weather you still may not figure out who or what you are up against.

Your friendly air traffic controller is your first source of information. Controllers can pass you target information directly using the Datalink system, or you can inquire about a specific contact you have locked up by selecting the DECLARE request from the AWACS communications menu.

Your IFF system automatically attempts to identify your L&.S target, and you can manually interrogate targets using the IFF interrogate button on the UFC. Your IFF system only identifies friendly aircraft and makes no determination between neutral and hostile aircraft.

Radar Sensitivity Indicator: Lower values indicate reduced target detection, acquisition and tracking ranges. the sensitivity decreases in high clutter areas such as when flying at low altitude or at presence of noise jamming.

Antenna elevation Scale and Caret: The antenna elevation scale indicates ±60° of antenna elevation. The scale is graduated 10° increments in the range of ±30° of antenna elevation, whit the full ±60° range being displayed over the entire tactical region of the radar display format. The elevation caret moves on the scale to indicate the current antenna elevation.

TDC Assignment Indicator: Indicates that TDC control is assigned to the radar page. The TDC Is assigned either by the mouse (clicking on the display) or by using the assigned key function. When assigned to the radar page, slewing the TDC causes the radar cursor (acquisition gates) to move on the display.

Target Range Caret/Closing Velocity: Current target range is indicated by the caret symbol. The symbol moves vertically along the right edge of the radar page and each large tick mark represents one-forth of the current radar range. Target velocity in knots is displayed to the left of the range caret. If the number is positive, the target is getting closer to you , and if negative the target is moving further away from you.

Launch & Steering (L&S) Designated Target: The L&S target is identified by a HAFU containing a "star" in place of the rank number. Mach and altitude information of the target are displayed to the left (mach number) and right (altitude in 1000 ft) of the "star".

Radar Acquisition Cursor: The Radar Cursor is a set of two vertical parallel lines displayed at all limes in RWS, VS, TWS, and STT. The cursor moves in response to up/down/left/right commands from the TDC. The numbers displayed above and below the cursor indicate the altitude coverage limits (in thousands of feet) of the radar scan pattern to the indicated range. Targets that are located above or below these altitudes are outside the the current scan of your antenna and won't be detected.

Radar Grid Line Scale: The horizontal lines are velocity reference lines in the VS sub-mode and range reference lines in all other sub-modes. These grid lines represent a quarter increment of the selected range or velocity scale. The vertical lines are the azimuth grid lines. The center azimuth grid line represents zero degrees (straight ahead) and each smaller line to the left or right represents 30° of bearing.

The Range While Search sub-mode is your basic search mode. It provides good detection of targets during both high-closure rate, head-on attacks, and low-closure rate tail attacks. Range scales of 5, 10,20,40, and 80 nautical miles are available. The antenna scan is set to 20, 40, 60,80, and 140 degree azimuth scan settings, and 1, 2, 4, and 6 elevation bars. RWS targets display as row radar hits except for the L&S target (if one is designated), which uses a HAFU symbol.

AOT Zone (dugout): This area is used to display angle-only-tracks (AOT). An AOT is a created when the radar cannot determinate target range (typically as result of jamming) Only AOT trackfiles display in this zone.

NCTR Option: (PB15) Toggles Non Cooperative Target Recognition (NCTR) on or off. When enabled, the radar attempts to identify (type of target e.g. MIG29...) the L&S target by analyzing the radar returns of the target.

MSI Option: (PB16) When enabled (boxed), data link targets (supplied by the E-2C AWACS) and the current A/A FLIR target (if the ATFLIR is autotracking an airborne target) are added to the radar display.

Track While Scan (TWS) sub-mode enables you to maintain awareness of the airspace nearby a primary target of interest with less chance of alerting the target of your intentions than in STT sub-mode. In TWS sub-mode, the radar scans a much smaller area in order to maintain a high update rate (every two seconds) on the primary target. As a result, the antenna azimuth scan and elevation bar selling combinations are limited to 20° / 2 bar, 20° / 4 bar, 20° / 6 bar, 40° / 2 bar, 40° / 4 bar, 60° / 2 bar and 80° / 2 bar.

Up to eight targets are traced, and ranked MSI HAFU symbols represent the targets. The L&S target is the primary (DT1) target, and a second target (DT2) may be designated. Additional targets in the area are represented as radar blips, although a radar blip temporarily changes to a HAFU symbol if the cursor is moved over it. If there is no L&S target when TWS sub-mode is entered, the highest ranked MSI trackfile is designated the L&S target.

Primary Designated (DT1) Target: In TWS, the L&S target is also known as the primary designated target or DT1. If a second target is manually designated using the TDC and designate keyfunction, that target becomes the new DT1 target and the previous DT1 target becomes the DT2, or secondary target.

Second Designated (DT2) Target: A second designated target (DT2) is designated to allow for improved multiple target attacks. The DT2. target is indicated by a HAFU containing a diamond in place of the rank number. Selecting Radar Reset (RST) deletes the DT2 target.

RAID Option: (PB 4) Toggles between normal and RAID TWS sub-modes. TWS SCAN RAID Is a "zoomed" TWS display, centered on the L&S target. It uses a high data rate scan that increases the probability of separating and displaying additional targets on closely spaced target groups.

Ranked Targets: Up to eight targets display on the TWS radar page as HAFU symbols containing their associated number. The rank number is not displayed for L&S target and DT2 target since the star and diamond cue are indicated whitin the target symbol.

Antenna Scan Centering: (PB 13) Selects automatic or manual antenna scan centering. Whit AUT selected, the azimuth and elevation scan center are changed to keep as many radar targets as possible in a scan volume. The scan volume and scan center are continual adjusted so that all or most of the targets are maintained on the display. Whit MAN selected, the scan volume is manually selected.

Cockpit	Basic Flight	BFM	Formation	M-Tactics	Building Campaings
HUD	Character	Basic ACM	Combat	W-Tactics	Building Missions
MDI/UFC	Disruption	Off-BFM	DO-BFM	SAMS
AA-Radar	Takeoff/Land	Def-BFM	DD-BFM	M-Builder
AA-Combat	Refueling	HO-BFM	Hi Aspect BFM	B-Areobatics
AG-Radar	Navigation	BVR	Prin-BFM	A-Areobatics
AG-Combat	Miscellaneous	ACM	Co-ACM	Weapons