Anti-Aircraft

The term Anti-Aircraft (AA) refers to any weapon or vehicle capable of effectively shooting down Aircraft. Anti-Aircraft weapons come in a wide variety, from Machine Guns to unguided rapid-firing Autocannons to guided SAMs and AAMs. The vehicles carry such weapons also vary greatly, from simple Technicals to IFVs. Some Anti-Aircraft weapons are carried by Infantry (called "MANPADs"), while others are stationary weapons that can be crewed temporarily to defend a position from enemy aircraft.

Both players and AI can utilize AA to defeat enemy aircraft. AI-controlled AA is somewhat more common, as player-controlled Aircraft are generally more common. Nevertheless, players are more likely to have and use powerful AA assets, if Red Air is expected to appear during a mission. AI-controlled AA is often simpler and less accurate, giving player-aircraft a better chance of survival.

Types of AA
There are several types of weapons that can be used against Aircraft. They are quite varied, with significant differences in accuracy, skill required, and expected damage to enemy aircraft.

Improvised AA
Some weapons that are not specifically designed to take down aircraft are nevertheless useful against them, but require plenty of skill (and luck) to use effectively in this role. The two primary categories of improvised AA weapons are Machine Guns and Anti-Tank Launchers. Both groups are far more useful against enemy Helicopters, while being almost completely useless against fast-moving Jets.

Machine Guns, and particularly Heavy Machine Guns stand some chance of hitting a Helicopter that's flying overhead. For the most part, it is better to shoot at the Pilot rather than hope to damage the aircraft itself, since even a Heavy Machine Gun may fail to damage an aircraft. Machine Guns are often fired while the helicopter is approaching the gun or moving away from it; This eliminates the need to lead the aircraft when firing.

Another option is to fire an Anti-Tank Launcher at the helicopter. Any AT launcher might work, but of course an ATGM has a better chance of hitting. AT is typically launched only when the helicopter is very close and relatively stationary, as the rocket/missile can easily miss a fast-moving helicopter entirely.

Autocannon (AAA)
Most Autocannons make useful weapons against aircraft. The higher the firing rate of an Autocannon, the better chance it has to hit the targeted aircraft. The heavier the shell, the better chance it has to damage the aircraft when hit. Multi-barreled Autocannons, as well as multiple autocannons firing in unison, can pose a significant threat to any aircraft, and particularly Helicopters.

Autocannons are relatively common weapons, found primarily on IFVs and some APCs. OPFOR also has the Zeus multi-weapon system (2 or 4 Autocannons synched together) that can be found as a stationary defense weapon or mounted on a Zeus Truck.

The most dangerous Autocannons are found in a system called "AAA" (pronounced "Triple-A"), where they are linked to a radar that can track the target aircraft and predict its path - eliminating much of the skill required to "lead" the aircraft as it flies past. This makes them exceptionally dangerous, capable even of shooting down fast-moving Jets in some circumstances. This system is mostly found on the Shilka Anti-Aircraft vehicle as well as the Linebacker.

Additionally, many Aircraft carry their own Autocannon which can be used to shoot down other aircraft.

SAM
A Surface-to-Air Missile ("SAM") is a guided, ground-launched missile that is designed to track aircraft through the air. Unlike an ATGM, the SAM is much lighter and faster, and can sustain the high-G turns required to keep up with a maneuvering aircraft.

The most common SAM launcher is the Igla, an OPFOR weapon which can be carried by Infantry and fired from one's shoulder. BLUFOR has a similar weapon called the Stinger. Both weapons are heat-seeking, targeting the heat coming off the target aircraft's engine. Both missiles can also be launched from a stationary defensive mount. Evading a heat-guided missile is difficult, as it requires the pilot to spot the missile themselves and take evasive action before it is too late. Many aircraft (particularly Jets) are fitted with a complement of flares that can be ejected to fool the missile, causing it to target the flares instead of the plane's engine.

There are also more dangerous types of SAMs in existence that track an aircraft by its radar signature (requiring the launcher to be linked to an active radar). These missiles are incredibly difficult to avoid once fired, though the pilot gets an advanced warning that their plane is being hit by radar waves, and thus has a better chance of starting evasive maneuvers in advance. Radar-guided SAMs exist in ArmA, but have not been seen in ShackTac to date.

AAM
Finally, Aircraft can be fitted with Air-to-Air Missiles ("AAM"s) that can be used to shoot down other aircraft. Both Attack Helicopters and Jets can carry these, though Jets do so more regularly.

Like SAMs, AAMs come in two varieties: Heat-Seeking and Radar-Guided. They are often much harder to dodge, since they are fired from a pursuing aircraft that is likely to get into a good firing position before releasing the missile - giving the target's pilot much less time to react.

Using AA
Players are occasionally required to use various types of AA to destroy enemy aircraft. The skill to use an Anti-Aircraft weapon varies from one type to another (see prev. chapter), and ranges from the extremely difficult (e.g. using Anti-Tank Launchers) to simple point-and-shoot (e.g. using SAM against Helicopters).

Improvised AA is typically very difficult to use, and should only be attempted by someone who knows what they are doing. Typically, the shooter will hold their fire until the target is very close, stationary, and/or flying directly towards or away from them. This maximizes the chance of hitting the aircraft at all, let alone shooting it down. Unskilled shooters can easily waste ammunition or valuable rockets on such an attempt. If there is no other AA weapon available, of course, even the unskilled may be required to take the shot.

Autocannons are simple to use, but require some skill. The shooter must be able to calculate the "lead" angle on the aircraft - judging its lateral movement speed and aiming the weapon ahead of the aircraft in order for the projectile to intersect with there the aircraft will be, rather than where it is. This is much harder with low-rate-of-fire Autocannons, but these are usually more powerful and may knock the aircraft out in one hit. AAA, of course, provides automatic "lead" prediction, making the shot extremely easy.

Firing SAMs is very simple - requiring the shooter only to aim the weapon and press the trigger at the right moment. The window of opportunity is also much wider, typically as the aircraft passes overhead or is making a lateral maneuver at low speed. The missile itself does all the rest.

AAMs are more difficult to use than SAMs, since the Pilot must maneuver their aircraft into a firing position and fire only once the target has minimal chance to evade. Nevertheless, once the missile is fired it is almost impossible to evade due to the short distance between the launcher and the target.

Evading AA
As part of their training, all Pilots must learn to evade various types of Anti-Aircraft fire. Depending on the type of aircraft and the type of weapon fired at it, evasion can be either very simple or extremely difficult. In most cases, the best way to evade AA is not to expose the aircraft to it in the first place. A single hit, even from an improvised or light AA weapon, can destroy the aircraft entirely.

Evading Machine Guns and Anti-Tank Launchers is typically very simple: The pilot avoids flying over enemy positions entirely, or overflies them at a high altitude when necessary. Avoiding an AT rocket once it has been launched is practically impossible, but won't be necessary at all if the aircraft is far above the ground. HMGs are similarly difficult to evade when fired from a short distance; Flying perpendicular to the shooter can make an aircraft much harder to hit, and turning the aircraft's stern instead of the cockpit towards the shooter can make it harder for bullets to get to the pilot and knock them out.

Evading Autocannons and AAA is significantly harder even at a high altitude. It requires the pilot to begin immediate evasive maneuvers. One of the most effective maneuvers is simply to break the line of sight to the shooter, usually by dropping altitude and hiding behind trees or terrain. Another way is to fly directly above the shooter, as most Autocannons cannot be pointed upwards at a steep angle. Increasing altitude may or may not help.

Evading a heat-seeker SAM or AAM requires very sharp evasive maneuvers in an attempt to overcome the missile's maximum agility, while also dropping flares to confuse the missile's targeting system. This requires the pilot to quickly identify the incoming missile first, as there is no early warning for heat-seeker launch.

Evading a radar-guided SAM or AAM is similar to evading heat-seekers, except flares do nothing against these. On the other hand, an aircraft will typically receive plenty of warning in advance once the launcher's radar locks on to the aircraft - allowing the pilot to maneuver before the missile is even launched. Retreating out of enemy airspace immediately is often the best way to prevent the launch altogether.