Air-Launched Weapons

Things that can be launched from aircraft. Also includes equipment to make an aircraft more effective.

Guns
"It's time to get medieval, I'm goin' in for guns."

- Dos Gringo's

The first form of anti-air combat, along with cans attached to wires (to foul an enemies propeller) Started when scout planes, the only type used before the Great War in a combat role, would bring pistols or small rifles in case they met an enemy scout. Then some pilots started fitting light machine guns to their planes, and it escalated from there.

From World War 2 onwards, for guns and cannons to be effective against enemy aircraft, bombers in particular, they needed to be either very large calibre like .50 cal or 20mm, or fast firing smaller weapons, such as the eight .303 Vickers K's on the Spitfire and Hurricane. This lead to the revival of rotary cannons as the fire rate to damage, or to even hit, an enemy increased dramatically.

Analysis after the war showed that somewhere between 20mm and 30mm seemed to be optimum in this role, especially if they contemplated using them against large bomber aircraft that could take a lot of damage and keep flying. Most of NATO standardized on the ADEN (UK) or DEFA (French) high-cyclic 30mm autocannon for fighter aircraft, the mechanisms of which were copied from wartime German designs; the US went, after the Korean War, with an electrically powered 20mm Gatling gun that fires 100 rounds per second, still their standard today after more than fifty years of continuous use. The Eastern Bloc went mainly with 23mm, then since around 1985, mostly 30mm autocannon of various designs.

At one point the US military (specifically, Secretary of Defense Robert McNamara) deemed guns outdated and built a series of jet interceptors (F-4 Phantoms) armed with only missiles, using AIM-9 Sidewinder and AIM-7 Sparrow guided missiles as their primary air-to-air armament, based largely on promises from the contractors that the then-new radar-guided air-to-air missiles under development would display unprecedented lethality and utility. After they took heavy losses in Vietnam to cannon-equipped MiG-19's and -21's, however (this due in large part to early AIM-7 radar-guided missiles being unreliable, and furthermore having been designed to be used beyond visual range--and indeed its guidance system required several miles of flight to pick up a stable reliable target lock--but in Vietnam the politically mandated rules of engagement required visual identification of every target, making the AIM-7 worse than useless, it was not only useless but also dead weight), they returned to adding Vulcan cannons as a backup weapon bolted on under the wings in "gun pods," and the F-4E variant that entered service in 1968 had the Vulcan cannon built in, with 1100 rounds of 20mm in its feed hoppers. (It should be noted though, that with updated rules of engagement and improvements in missile guidance systems, no fighter based gun pod has ever been fired. Thus potentially validating the idea of their obsolescence)

Unguided rockets
One of the most basic air-to-air weapons, these explode either when they hit something or when they've flown a certain distance. One of the most impressive of these is the Genie, a tactical nuclear rocket designed for shooting down bomber squadrons, though it is uncertain whether Soviet bombers approaching US airspace would have obliged by flying in conveniently vulnerable tight formations. There is also at least one case where air-to-ground unguided rockets have been used to shoot down an enemy fighter, over the Beka'a Valley, Lebanon, 1982.

Some U.S interceptor aircraft designed in the 1950s carried launchers for large numbers of unguided 70mm rockets of a type normally used for air-to-ground use, instead of gun armament, on the theory that shooting down large Soviet jet bombers required more punch than even electric Gatling autocannon could provide. Fortunately this was never put to empirical test.

They have been in use for decades, and some sources say the French experimented with them in World War I, but with mediocre results (it's a bit dangerous to launch a rocket that exhausts vast plumes of white-hot flames from an airplane built of wood and cloth) at the time.

The first practical use was by USSR against Japan in 1939. While Soviet "rocket shells" are far more famous for their Free Rockets Over Ground use, compatible launchers were installed on many planes. Those rockets weren't very accurate, had fragmentation warheads with timed fuses (the early versions of those were rather unreliable), and greater range than machineguns or aircraft cannons; as such, they were best used all at once at long range, and if possible, before the enemy regroups, immediately followed by a conventional dogfight. Rockets were not exceedingly effective in this role, but useful enough, and later launch systems were installed on variety of fighters as auxiliary weapons, as well as on ground assault planes. In 1940-s many other versions appeared. As a curious note, Soviet aviation had love-hate relationship with turbojet rockets since 1940-s when they were modestly marked as "improved grouping" types, and until 1950-s: those were more accurate, yet more demanding to the launcher and upgrades are harder (therefore, slow and rare) - they spin and thus sensitive to full moment of inertia, and any change requires re-balancing the whole thing, while finned rockets allow to slap a new warhead on or screw a new fuse into it much easier.

The Japanese were impressed enough to try this too, and developed both surface-to-surface and air-to-air rockets by 1942-43 - but couldn't catch up to several decades of work in a few years, and their few experimental "aerial rocket bombs" with phosphorous cluster warheads were at best scary, yet ineffective (because they didn't inflict enough of damage), and at worst barely noticed at all (when the Japanese either had even worse timers or were unreasonably optimistic and tried to snipe bombers at extreme range, rather than catch them in a barrage as large as they could from as close as they could get without being hit).

Unguided rockets were much more common in World War II, and were a favored choice for ground-attack and close-support missions in the US and UK air arms, as an aircraft that might only be able to carry a single 500-pound bomb could have racks under the wings for six or eight rockets. Rockets also caused less danger to friendly troops on the ground as their warheads were relatively small and so had smaller bursting radii.

Infra-red guided missiles
"Fox Two!"

- Brevity code for firing one of these

AKA "Heatseekers", these are designed to home in on the engine exhaust of an enemy aircraft or just the heat generated by its friction. Before being launched, you need to have a lock on a target, indicated by a visual display and the characteristic tone (Beeeeeeeeeeeeeeeeeeeeeeeeeeepppppppppppppppppppp! or sometimes grrrrrRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR! in the pilot's headphones)

Short-range (as in, within visual range) weapons (i.e. under 20 kilometres, sometimes under 10), they are standard on all fighters today and many a strike aircraft. They come in five Technology Levels:

Tail-chasing
Can only be fired from a narrow (30 degree) area behind the target. This is fairly hard to do and requires a firing solution very similar to that of a firing solution for gun armament, though with the advantage of greater range. The earliest versions were created just after the Second World War and their circuitry was all vacuum tubes, no transistors. Their use in combat had mixed results at best. Under perfect circumstances they could be very deadly, but were also very unreliable because they were prone to losing target lock if, for instance, the reflection of the sun from the surface of a calm ocean happened to pass through the missile's sensor's field of "vision." They were also very vulnerable to flares and other countermeasures.


 * The original AIM-9 Sidewinder up to the Vietnam-era AIM-9E
 * The K-13/AA-2 "Atoll" the Russian copy, and many other 1960s-1970s Soviet air-to-air missiles, up through the IR-seeking version of the big AA-7 "Apex," had sensors like these.

Rear-aspect
These can be launched from a larger angle, but you still need to be behind the target. Tend to be smarter and more agile than earlier versions.


 * The late 1970s AIM-9J version of the Sidewinder, the first to feature sensor circuitry cooled with liquid nitrogen to improve its sensitivity and reliability
 * The R-60/AA-8 "Aphid" from the USSR, found on aircraft like the MiG-23 interceptor, also at least theoretically mountable on some models of the Mil-24 "Hind" helicopter gunship

All-aspect
Sensitive enough to detect and get a reliable lock on the leading edges of the wings, which are heated by air friction from flight at jet speeds, they can be fired at the target from any angle provided you have a good shot. It's much harder to avoid too.


 * The US AIM-9L, known as the "Wish Me" by Harrier pilots in the Falklands because it was so effective, they just needed to "wish" the target dead. Current mass production version is the AIM-9M, said to be just a little smarter and more agile than the L
 * The IR-guided version of the Soviet AA-10 "Alamo" was believed by Western experts to be in this class. This is a good place to note also that the Soviets in many instances designed air-to-air missiles with a certain "chassis" of solid rocket fuel engine, fuselage, and warhead, and then manufactured both a heatseeker and a radar-guided version, to offer their pilots greater tactical flexibility; typical loadouts might be two IR-homing plus two radar-homing.

Off-boresight
The problem with the older missiles is that you need to be pointing your nose at a reluctant target. With these, coupled with a Helmet-Mounted Sight, you just need to look at a target (up to 60 degrees or so off your centre-line) and fire.


 * This technology was developed by the US in the mid-1970s as a result of analysis of air combat in Vietnam, analysis of existing systems, and large-scale wargames and then abandoned for decades as it was felt to be too expensive to be practical, except for some small-scale trial use by the US Navy in the late 1970s.
 * The R-73/AA-11 "Archer", which entered Soviet service in 1985, is at least theoretically capable of use in this mode, but has never been used in combat, and at least some reports suggest that very few were ever manufactured.
 * R-73s scored many kills during Eritrean–Ethiopian War, though one must those that such missiles were probably old stocks.

Imaging infra-red
Can see "images" rather than single points of heat and can go for the more vulnerable targets rather than the exhaust. Considerably "smarter" than earlier designs, they are at least theoretically much less vulnerable to countermeasures like flares.


 * The US/UK/Australia joint design AIM-132 ASRAAM, as carried by the Typhoon.
 * The US AIM-9X. Is also a high off-boresight missile, with a full 90 degree search cone.
 * IRIS-T built by a German-led consortium.
 * The French Mica-IR, designed for the naval version of the Rafale jet, is reported by some sources to have this capability

Radar Guided Missiles
""Fox One!""

These missiles guide in on the radar reflections of a target and come in varying forms.

Beam-riders
These missiles ride a radar-beam towards a target. This is a very unreliable system and these missiles were soon surpassed. These are mid-1950s technology.


 * The Soviet K-5/AA-1 "Alkali"
 * The US AIM-4 Falcon.
 * There were also tail-chasing infrared homing and semi-active radar homing versions of the AIM-4 Falcon, a small number of which were used in Vietnam. Their performance in combat was extremely unimpressive, and they were dropped from production in favor of the newer AIM-7 and AIM-9.

Semi-active radar-homing
These missiles home on a radar reflections from a target aircraft that is being "painted" with the radar system of the jet fighter that launched the missile (tactics were developed for one aircraft to illuminate the target while another fired the missile, but it is uncertain whether this was ever tried in actual combat, and this general category of guidance system is now obsolescent). This does of course require the firing aircraft to retain a lock on it, which is by no means easy if the target aircraft is maneuvering. This generation of radar-guided missiles was the first to have circuitry included that made them smart enough to home in on a radar jammer. These were introduced around 1960 and have been obsolescent since the advent of reliable active radar homing missiles in the mid-1980s.

Note that this homing scheme is still relevant and commonly used in Surface-to-Air Missiles fired from ships and land sites. The chief disadvantage as an air-to-air guidance scheme (that the attacker has to follow the target around while "painting" it with radar) is not an issue for a large land installation or ship that has large radars that can look in any direction, and it allows for cheaper and simpler missiles to be used to the same effect. That in turn allows each site to have more missiles available for the same space and money.


 * The US AIM-7 Sparrow (early versions like the AIM-7D and AIM-7E used in Vietnam were mediocre performers, the late-production AIM-7M some US Air Force and US Navy fighters used in the 1991 Gulf War were much better performers, not only because the technology had improved, but also because they were no longer being used under restrictive rules of engagement requiring pilots to hold their fire until they were so close to the target that the missile could not lock on) The "Aspide" manufactured in Italy is an improved copy built under license, still in service.
 * The Soviets had a radar-guided version of the AA-2 "Atoll" using this technology.
 * Soviet AA-3 "Anab"
 * Soviet AA-4 "Awl"
 * Soviet AA-5 "Ash"
 * Soviet AA-6 "Acrid"
 * Soviet AA-7 "Apex" (this and the AA-6 were very large, heavy radar-guided missiles carried by jet interceptors, intended for use against large American bombers; they were by far the most common missiles of this class produced, at least in Eastern Bloc service)
 * Soviet AA-10 "Alamo" had a radar-guided version with this technology, along with an all-aspect IR seeker version
 * Britain's Skyflash is another enhanced Sparrow clone, still in service today.

Active radar-homing
""Fox Three!""

These missiles have their own radar seekers on board to carry out the final intercept, allowing them to be launched from long distances and left to do their job (leading to them being termed as "fire and forget" missiles). With some aircraft, one plane (or an AWACS) can light up the aircraft and guide missiles from multiple aircraft in before the missiles go active. This sort of guidance system is also very common on anti-ship missiles.


 * The US AIM-54 "Phoenix," developed in the early 1970s, noteworthy for having an effective range well in excess of 100 nautical miles, possibly the longest-range air-to-air missile ever produced. It and the F-14 "Tomcat" jet fighter that carried it were developed concurrently. As far as can be determined, it was never used in combat by the United States. This site asserts that the Iranian Air Force scored several kills with the AIM-54 Phoenix during the Iran-Iraq war, including Mig-25s and one occasion where a single missile destroyed three of four Mig-23BNs flying in close formation.
 * The US AIM-120 AMRAAM, also called the "Slammer". It was developed in the late 1980s, and while it entered service just a touch too late to see action in Desert Storm, come Operation Southern Watch one year later it proved to be as lethal as the contractors had promised the AIM-7 Sparrow would be thirty years before. Current production version is the AIM-120C with an effective range of 30+ miles, and AIM-120D, with a 65+ mile effective range, is currently in the testing and evaluation stage of development. Smart, agile, and highly lethal, it appears to be everything they promised radar-guided air-to-air missiles would be back in the 1950s.
 * Soviet AA-9 "Amos," similar in role to the AIM-54 Phoenix.
 * Russian AA-12 "Adder," though publicly available information about it is almost entirely speculation and rumor, at least in the West; some sources describe it as comparable or superior to the AIM-120--indeed, the Adder is sometimes nicknamed the "AMRAAM-ski".
 * The under-development Meteor system for the Eurofighter Typhoon
 * The French Mica-R air-to-air missile developed for the naval version of the Rafale has this technology.

Directed-energy weapons
While jetcraft have yet to be shooting each other out of the sky with Star Wars-type lasers/whatnot, this shows use on a large airborne craft (read: modified jumbo jet) for shooting down ballistic missiles on their way up, and in theory could work against an aircraft too by detonating its fuel and weapons load.

Iron bombs
'Iron' means there's nothing really special about these. You release, the bomb falls, and (hopefully) it blows up what you aimed it at. The first ones of these, at least according to The Other Wiki, was from unmanned balloons sent over Venice. Not many hit. Then again, this was 1849.

Most bombing was done by letting the ordnance drop and just free-fall down to the target. Very difficult to avoid, but also difficult to aim--this is why the main methods were either to divebomb (ride the bomb a slight way to the target in a dive, centering the target in the gunsight before releasing; can be very accurate, especially if the pilot waits until the last possible moment to drop the bomb and pull out of the dive, but also extremely dangerous to the pilot) or to carpet bomb.

The former limits it to high-performance (and low payload) aircraft; the latter tends to be hit and miss and miss and miss and hit and miss, which can get messy if you only have a single thing to destroy. On the other hand this can be a useful tactic if you have a known location for a large enemy unit on the ground; in Korea the US used B29 bombers to carpet-bomb Chinese units massing for human wave assaults, and since Vietnam has used the term "ARC LIGHT" to describe this use of heavy bombers to carpet-bomb the very bejesus out of enemy units on the ground, the term having originated with the semi-secret project to study the feasibility of using B52 bombers, designed originally to carry nuclear payloads, to haul many many tons of conventional "iron bombs," instead (30+ tons with some modificiations).

Anything that helped with bombing was vital; according to at least one source, the USAAF's 'Norden' bombsight had one of the highest levels of secrecy, although it didn't quite live up to its initial hopes, then again it was developed in the early 1940s. The sheer inaccuracy of bombing with these things at night due to navigation problems (only one in five bombs ended up within five miles of the target) was a major factor in the British decision to area bomb German cities.

The third method is the "lob-toss", which involves chucking the bomb while in a climb. This was once regarded as only really accurate enough for nuclear delivery, where it also serves the purpose of giving you more time to clear the area. These days, however, with modern avionics and CCIP/CCRP HUD bomb sights universal since the 1980s in modern Western close-support and strike aircraft, a "toss" delivery can be very nearly as accurate as dive-bombing, even with "iron bombs." With smart bombs, this kind of delivery is usually good enough for the bomb's guidance system to take over and do the rest.

Another reason they are called 'iron bombs' is because most of their weight is from the steel casing, with less than half from the actual explosives. The aim of these bombs are not usually to kill from the explosion (though it is handy against armoured targets, or when the objective is to destroy, for instance, a vital bridge, or to make craters in the runways of an enemy air base) but to kill and wound from shrapnel which can be deadly from several hundred metres away.

Since 1965 some Western air forces have used "low drag bombs," a variant type of "iron bomb" that has a long, slender, pointed casing for maximum streamlining and minimum air resistance. This reduces drag on strike aircraft that are carrying them on external racks or hardpoints, permitting slightly higher speeds. They also fall faster with less air resistance once released, making them more accurate because they are less affected by wind; additionally they allow aircraft to dive-bomb accurately at shallower angles than older designs required.

There are also "retarded bombs." No, this isn't a comparison to smart bombs. These have some kind of parachute or balloon system built in to slow their fall, to allow the attack aircraft dropping them more time to get away; these are for very, very close, very, very low level work, for missions done at such low altitudes that the blast and shrapnel of the bomb would endanger the aircraft dropping it. They first appeared around 1970, in the form of the "Snake Eye" system, a set of fins that could be bolted onto an existing bomb that would open up like an umbrella as it was released by the aircraft.

Another variant on the "iron bomb" concept, in the sense that it is an inexpensive container of nastiness that an aircraft drops on target, lacking any particular guidance system other than the skill of the pilot, is napalm, basically gasoline or jet fuel mixed with a chemical gelling or thickening agent, put in a container with a fuzing mechanism designed to ignite it on impact as the contents splash out. Cheap, effective, and politically controversial, it was created during the Second World War and has been in very common use ever since.

Fuel-Air Explosive/Thermobaric bombs
These were first put into service around 1965, just in time for Vietnam. The FAE is deceptively simple. Imagine a half-ton canister of propane, liquified petroleum gas, or something similar. Imagine putting shackle points on it so that it can be slung on an attack aircraft's bomb rack. The canister will need to be modified, of course. Instead of detonating instantly when it gets to the ground, it has valves on it to release the contents and mix them with air in the appropriate proportions for rapid combustion, plus a time fuze to give the payload time to mix with air for a few seconds, plus a detonator or incendiary device of some kind to initiate the reaction, the reaction in this case being an enormous explosion that can kill everyone inside an underground tunnel complex beneath it by overpressure, or clear an instant helicopter landing field in triple-canopy jungle; they're also quite useful for clearing land mines. The designs have been refined over the years but the basic concept remains the same. Instead of a solid high explosive filling, they use a mixture of flammable vapor and air, or in some newer Russian designs, small particles of highly flammable solids in air, to create the big bang boom.

Smart bombs
Everyone became an expert on this from coverage of the first Gulf War in the United States. It's Older Than They Think; folks seriously started looking into guided munitions after the Spanish Civil War and the Germans used radio-guided glide-bombs with some success in World War Two. This is basically the idea of somehow getting the bomb itself to adjust where and how it falls based on what the aircraft is doing. The main one that most casual viewers are familiar with are laser-guided (which find something that's being illuminated with a special laser, possibly operated by ground troops, though some modern strike aircraft have their own target illuminating laser), going back to the late 1960s, and teleguided (which adjust while the bombardier keeps the target in his sights, or in some instances the bombardier looks at a television image transmitted from a TV camera in the nose of the bomb and uses that to steer it onto the target by remote control). Typical targets for "smart bombs" may include anything from the foundation of a bridge to a single individual armored vehicle to an enemy command post building.

A new wrinkle from the Yanks is satellite-guided bombing, which comes in surprisingly inexpensive bolt-on kits for iron bombs. As long as they have the right target location (they can't follow a moving target, though), it gets hit. (Sadly, this is still subject to human error--the Chinese embassy in Belgrade was hit by one of these due to an out-of-date map. The bomb did its job, but garbage in, carnage out.) GPS guidance is slightly less accurate than laser guidance, but the tailkits are cheaper than laser-seekers and the plane does not need to keep a laser pointed at the target.

Sea Mines
Usually either a small Sea Mine or iron bomb in a better sealed casing (and with different fuses, etc), dropped with parachute - but not always.

Most major participants of WWII had at least one type of these. UK had A Mark I to A Mark VII. USA had Mark 13 (without parachute, magnetic), Mark 15 (acoustic), Mark 19 (drifting, with relatively small charge), Mark 25 (magnetic, with acoustic variant) and Mark 25 (magnetic). USSR had AMG-1 (moored, modified common mine), Р-1 (moored river mine), MIRAB (ground, magnetic, small charge), AMD-1-500/AMD-1-1000 (ground, magnetic mines from 1942, number for half-ton or ton). Italy had Delta (ground, magnetic). Japan had Aircraft Type 3 Mark 2 Model 1 (horned, drifting). Germany had LMA (British designation "GD") to LMF (British designation "GP"). France had some prototypes, but nothing in service.

Later there, of course, was some development, though not always in the same direction. USA in Vietnam War had "Destructor mines" designated DST, which were converted common bombs (and still usable as iron bombs).

Cluster munitions
These occupy a place somewhere between "iron bombs" and "smart bombs" in both technology and application. It is basically a bomb casing that is designed to split open fifty or a hundred meters in the air over the target and discharge hundreds or thousands of "submunitions," basically grenades. They are extremely useful against dug-in infantry, and, with slightly larger shaped-charge submunitions, can damage or destroy even armored vehicles in the target area, as a tank's armor is generally thinnest on the roof. Incendiary munitions usually work better this way too, since it's less about dumping more fuel on things that won't burn on their own and more about hitting something that will. This idea is also Older Than They Think, having first been developed by the Soviets between the World Wars, copied by the Germans during the war, then developed further by all parties in the postwar era. Politically controversial because they sometimes litter the area with duds, which later endanger civilians in the area. A notable example of its infamous-ness was the massive drama created when Carlos Cardoen, a Chilean entrepreneur owner of Cardoen Weapons, sold this type of weapons to Saddam Hussein, though he argued that the transaction was well known for the US and it was done before the second Gulf War.

Some types of cluster munition can be used to lay minefields from the air, using land mines that arm themselves shortly after reaching the ground.

Since 2000 we have seen the advent of cluster bombs with smart submunitions, which have sensors allowing them to seek out and destroy armored vehicles as they fall from above. These have been used in combat and appear to be every bit as lethal--and expensive!--as that sounds.

In 2008, the Convention on Cluster Munitions was signed in Dublin, banning signatories from using them, although many major states aren't signatories (the UK is though).

Rocket pods
Commonly found mounted to helicopters or light attack aircraft, you just aim at the target and let off a salvo of explosive rockets. They are most often used to shoot up lightly armed ships and road convoys, as well as to give fire support for the infantry when carrying out an airmobile assault. Prior to smart bombs and air-to-ground guided missiles, they were once the weapon of choice for close support aircraft, as the larger rockets had a chance to at least damage even the largest, heaviest tanks. The Russians have always loved these, and bolt multiple huge cylindrical launch pods with dozens of these rockets onto helicopter gunships and close support aircraft. They are slightly less common in Western services than they once were, due to advances in guided missiles.

Guns
Airplanes and helicopters can provide quite a lot of dakka. This can be a strafing run from a Sopwith Camel's machineguns, up to the machinegun/cannon combo mounted on later Spitfires, then through the 30mm GAU-8 Avenger that the A-10 is built around. And then some--the AC-130 gunship ("don't think of it as an airplane, think of it as a flying castle of doom)" flown by the USAF currently mounts a 25mm Gatling cannon as its small gun. Also on board are a 40mm former ground-to-air cannon (now air-to-ground) and a 105mm howitzer plus extremely sophisticated sensors and fire control computers allowing it to find targets on the ground with great efficiency and engage them accurately.

Missiles
These aren't limited to blowing up planes. Almost all the guidance systems above can be used to chuck a missile at something on the ground you don't like. One of the more fun variants is the homing antiradiation missile, meant to find and home in on radar antennae used by antiaircraft missile installations--especially radiation-filled radar sites. The USAF calls this sort of thing 'Wild Weasel' and the US Navy calls it 'Iron Hand.' Other air forces tend to use terms like SEAD ("Suppression of Enemy Air Defenses"). Since the aircraft is basically going for as close to a Scope Snipe as you can get with radar-seeking and radar-tracking missiles, some units adopted 'YGBSM' as a semi-official motto: 'You Gotta Be Shitting Me!' It used to be the case you could switch off your radar and make the missile "go stupid", but modern missiles can remember the location of radar sites, so your best option is to run for your lives.

The anti-shipping role requires someone to actually find the target, something that involves ships, submarines, other aircraft or satellites; it tends to be rather dangerous to just fly out and look for it and hope for the best, as naval vessels tend to be absolutely bristling with surface-to-air missile launchers and have bigger, better, more powerful, higher-performance radars than anything that's readily portable on the ground. Flying low to hide from radar amid the "ground clutter" doesn't work so well at sea, either. And of course naval vessels also tend to bristle with anti-ship missiles also; analysts have called modern naval vessels "eggshells armed with sledgehammers," but that is perhaps a discussion topic for a different page.

Anti-shipping missiles (no, not that kind of shipping!) themselves tend to be very large, in some instances basically smallish robot airplanes in their own right ("cruise missiles" is one term for these), with very large warheads, for obvious reasons; these typically skim only a few feet above the surface of the ocean at just under the speed of sound or are launched from 150 miles plus and fly at stratospheric height. Sometimes "cruise missiles" are also used against land targets, such as airfields. Some "cruise missiles" and anti-ship missiles in the Cold War era had tactical nuclear warheads. This was an area far more studied by the Soviets than the Americans, who had the naval aircraft to do closer-ranged attacks.

From the 1930s onward, attack aircraft have been able to carry and launch torpedoes at ships, though these days it's much more likely to be a naval helicopter than a jet attack aircraft that makes the launch... and torpedoes don't just go in a straight line just under the surface of the water any more. From the 1960s on, torpedoes have had built-in sonar guidance systems that allow them to track down even submarines under the surface. Indeed, given the relatively short range and low speed of a torpedo traveling underwater (80km/hr is said to be barely possible for a few designs), compared to a guided anti-ship missile flying through the air (800km/hr is not out of the ordinary) and general fragility of the system--they must be lowered rather gently into the water--torpedoes launched by aircraft have since the 1960s been very much a specialized tool used almost exclusively for antisubmarine warfare. During the Second World War, a specialized type of attack aircraft, a "torpedo bomber," had to make a low, slow run in a straight line just above the ocean surface--an extremely risky tactic, as naval vessels even back then bristled with antiaircraft guns and tended to be protected by fighter aircraft as well--arm the torpedo, drop it into the water pointed at an enemy ship no more than a few hundred meters away, and hope that it hit the target. Nowadays hovering helicopters lower sonar search devices into the water and then send a homing torpedo (and homing torpedoes have existed since World War II, but were expensive experimental weapons then, with crude vacuum tube sensor circuitry and even preset search patterns encoded as punched holes on rolls of paper like a player piano; the homing torpedo did not come into its own as a weapons system until the 1960s) on its way when they have a likely target, which will almost always be a submarine.

American AirLand Battle doctrine during the Cold War envisioned use of large number of helicopter gunships heavily laden with, for some designs, up to sixteen long-range antitank guided missiles, for use not only as highly mobile antitank missile platform but also to go deep behind the forward edge of the battle area and attack Warsaw Pact second-echelon units before they got to the front. (However, the deep attack concept only was done at the tactical rather than operational level and Apache gunships with their Hellfire missiles weren't deployed in Europe until late 1987.) The Soviets also built helicopter gunships and armed transports but they were general purpose battlefield close air support platforms akin to a rotary Il-2 Shturmovik, as the antitank task fell upon other ground-based systems.

There have been, of course, multiple generations of antitank guided missiles, and many designs can be set up to be launched from aircraft as well as from vehicles. The earliest were wire-guided, circa 1960 (gunner squints into binoculars and attempts to steer the missile into its target with a tiny joystick on the first types, on later types gunner only has to hold the crosshairs on the target to make the missile home in on it). Then laser-guided designs appeared around 1980, requiring only the latter, hold-the-crosshairs-on-target guidance by the gunner, and can also be fired in indirect mode, in which the firing aircraft or vehicle lobs them over an intervening obstacle, such as a ridge line, while someone on the other side illuminates the target with a laser, allowing the firing unit to engage without a direct line of sight. Each of these systems had the disadvantage that the gunner could only control one missile at a time, reducing his practical rate of fire significantly--some have such long range that it could take half a minute or more to get from the launching aircraft to the target. Since the early 1990s, true fire-and-forget antitank guided missiles have been available, allowing, under ideal conditions, the gunner to engage targets as fast as he can get a positive target lock and send them on their way; these missiles are smart enough to do the rest themselves.

Guidance systems for air-to-ground guided missiles vary. Current trends for fire-and-forget systems are to imaging infrared TV cameras and high-resolution millimeter-wave active radar systems, interpreted by a small cheap onboard computer, but every imaginable system has been used. Laser guidance has the disadvantage of requiring target illumination but by the early 21st Century it has become very inexpensive indeed, at least for Western air forces.

And for fixed-wing aircraft specifically, in the early 1970s, the US Air Force and US Navy got the AGM-65 "Maverick" air-to-ground missile, early versions of which were television-guided by the operator. Over time the design got newer and better guidance systems, and larger, more effective warheads to the point where current versions (the AGM-65G) are fire-and-forget weapons with a range of many miles, sensors that can function in total darkness, a warhead that is comparable to the high explosive filling of a 500-pound iron bomb, and which is smart enough and versatile enough to follow moving targets, like an individual truck or tank, or to lock onto a particular building, or a parked aircraft, or track and strike a maneuvering ship, as examples. Many other nations have weapons of approximately comparable capabilities in inventory, at least on paper. Some are much lighter and smaller, like the Brimstone (UK), allowing attack aircraft to carry significantly more of them, though the smaller ones, of course, lack the humongous warhead of something like an AGM-65G.

Rocks
When training with bombs, sometimes an aircrew will use inert practice bombs. They weigh around the same, filled with roughly concrete, and are meant to act about the same, although without the environmental problems that blowing up a quarter-ton of explosives would bring, such as having to send people out to do the ticklish job of digging it up and destroying it if it turns out to be a dud. This still leaves some impressive craters. Then someone realised that if you can laser-guide a quarter-ton of concrete onto, say, a building, then what do you need explosives for? As an added advantage, this tends to kill fewer innocent bystanders.

Yes, the USAF is so obsessed with precision guided munitions that it laser-guided ROCKS. Wile E. Coyote would be proud.

Radar
Radio Detection and Ranging. Send out a radio pulse, find out when and how it gets back, and show a blip roughly where it is. It's pretty good at finding a chunk of metal flying through what's normally empty sky, although early radar wasn't as reliable. Radar's useful at sea, too. This started on ground to help detect incoming planes, but was developed so the planes could have a decent set. Not to mention AWACS aircraft that carry a BIG radar.

This was invented by the British and Germans in the late 1930s, pretty much independently and proved decisive in the Battle of Britain. The US independently developed this technology for naval use just before the war.

Anti-radar and Stealth
There's a few things you can do about the enemy having radar finding all your aircraft.

You can of course just sit there and take it, hoping to outperform the defences they can toss at you. A B-52 is very findable on a radar, but if it stays out of reach and keeps pelting cruise missiles at you, then you'll still have problems. The SR-71 Blackbird was meant to simply outrun interceptors and incoming missiles. The U-2 reconnaisance aircraft was believed to be capable of flying higher than any known existing Soviet surface-to-air missiles around 1960, but this turned out to be incorrect.

Then you could try to make the radar not work. Blowing it up is ideal (see the earlier Wild Weasel mention), but if that's not available, you can at least make it useless. Whether dumping chaff at a radar-guided missile or using jammers to mess up the radar signal, you're going to still be seen but not well enough to actually get hit. Hopefully.

The SR-71 mentioned above helped show another property. Properly made and shaped, some aircraft can look less threatening than others. This being the Cold War USAF, a lot of money was poured into the idea. The result: 'stealth'. Various tricks like shaping, radar-absorbent materials, and other stuff that I'm not cleared for. You have to keep one thing in mind though. Stealth is low observability, not an Invisibility Cloak. In practice it drastically reduces detection range of radars which can leave huge gaps in the defense grid, through which a stealth plane can slip through. In air combat the opponent also likewise has to come a lot closer before his radar can lock on. The only aircraft known to use it, so far, are these:
 * F-117 Nighthawk. Called a stealth 'fighter', it's really just a ground attack aircraft. In service since the late 1970s, it started out as a top-secret black project initiated for the specific purpose of building stealthy military aircraft. It achieved that goal, and the plane would later be revealed to the public, and take part in the various wars of the 1990s and early 2000s with great success. However, one Nighthawk was nevertheless shot down during the Kosovo War, the circumstances of the event still remaining a topic for debate. Sadly retired in the late 2000s.
 * B-2 Spirit. Called a stealth 'bomber', the Spirit really is a strategic heavy bomber, capable of striking anywhere in the world (with tanker support), passing through air defenses as if they were not there, and unleashing major destruction. The thing's cost is upwards of 2 billion US dollars apiece (literally, more than worth its weight in gold), and it's meant to really not look like any other bomber, whether you're looking at it with radar, infrared, or just your eyes. Visually, it appears to be a big black flying wing. On radar, it appears to not exist. Unless you're using the ADF rader that detects it via the disturbances it leaves in the air behind it. So far, it has lived up to its purported capabilities in all its deployments, and the only B-2 loss until now has been due to a peacetime crash.
 * F-22 Raptor. This one's a real stealth fighter, although it's hard to say how good it is. There aren't m any that can match it yet, and the US is pretty reluctant to talk about how well it works too. Just check out its description here to get some idea of what this bird is like. Sadly, only 187 were ever built, the last of which rolled off the production line in December 2011. It however is quite literally the Super Prototype of the...
 * F-35 Lightning II. If the F-22 is the Cool Plane equivalent to Elite Mooks, then this is Goddamned Bats for enemy ground forces. Not as good a dogfighter as the F-22, the F-35's hat is ground attack similar to the F-117. It's real boons however are its VTOL capability, advanced ECM suite and comparatively lower cost when compared to the F-22: the US military ordered more than 2400 planes. Unfortunately, the project is plagued with delays (introduction in 2016 at the earliest) and overspending (the current projected costs of the program are 323 billion dollars).
 * Counted past 391 billion, but cancelled due to having far too many problems apparently not solved quickly enough.
 * Sukhoi PAK FA T-50. It is intended as Russia's answer to the F-22 but it's still in the early prototype stage. According to the designers, it's less stealthy than the F-22 but more nimble.
 * Chengdu J-20, another prototype stealth fighter design but this one's from - surprise, surprise - China. It's Chinese name fittingly translates as "Annihilator Twenty".
 * Possibly the unmanned RQ-170 Sentinel, dubbed "The Beast of Kandahar" after appearing in photos on blogs and only recently confirmed as existing by the USAF.

Electronic countermeasures and electronic counter-countermeasures (ECM and ECCM)
Flares are what they sound like and are used to decoy IR-guided missiles. Note that newer generations of IR-guided missiles have become smarter and are less likely to be fooled by flares than they once were.

Chaff consists of strips of aluminium foil cut to a certain length (it's a formula involving radar frequency and the wavelength of the frequency that particular type of radar you're targeting uses) and chucked out in clouds from planes or ships to lure off radar-guided missiles, causing a cloud of thousands of phony "blips" to be created from the radio reflections thus created, at least until the aluminum foil bits fall to the ground.

This can backfire though: in the Falklands War, a British frigate successfully decoyed two Exocets, resulting in one acquiring another target, namely the merchant ship Atlantic Conveyor and hit. The ship was sunk, with the loss of 12 men and also ten helicopters meant for the land operation. Thus the Marines had to walk...

And there are radar jammers, which are basically high-powered radio transmitters using the same frequency as your enemy's radar, which (you hope) will overwhelm his signal and cause interference, perhaps temporarily blind or even, if you are having a very lucky day, burn out his radar equipment. They have been standard equipment on ground-attack aircraft for decades now. However, radar-guided surface-to-air and air-to-air missiles have since the 1970s usually incorporated circuitry that allows them to home in on an active jammer, so leaving it turned on all the time is generally regarded as unwise. Ground-based radar jammers are likewise very likely to get a visit from aircraft carrying antiradiation missiles--see the section on anti-radar tactics above.

And many modern radars are "frequency agile" or "frequency hopping," meaning they jump from frequency to frequency many times per second according to a complex pattern that - they hope - airborne jammers can't figure out and jam.

Warning Systems and Electronic Support Measures (ESM)
It's useful for a pilot to know when someone's locked on to him or her. Radar Warning Receivers (RWR) and Laser Warning Receivers (LWR) can tell you if a radar or a laser has locked on to you with an audible tone in your headset.

More advanced RWRs (which are also mounted to ships) are systems that can tell you what type of radar is scanning or locked on to you, which generally narrows down enemy type a lot.

Unfortunately, RWRs and LWRs are completely useless when faced with Infra-Red (IR) weaponry such as the AIM-9 Sidewinder and R-27T Alamo.

The latest aircraft can use something called data fusion: put simply, they can collect information from other aircraft and use it to their advantage. For example, Plane A might spot an enemy aircraft (Plane B) and relay the data to Plane C, who can then engage the target using appropriate techniques.