Air-to-air missiles and changing air warfare scenario
Air-to-air missiles are part of modern battlefield which could help the pilots to lock on early and decimate enemy aerial control of the skies. It gives the opportunity to go for full dominance of skies in view of lethality, accuracy and speed as one fire can ground an expensive enemy asset much before the war begins. Thus, air warfare is seeing lot of change where engagements with the enemy take place from a beyond visual range.
As the fighter planes are trying to be hidden from the enemy screens, the modern air-to-air missile denies this opportunity from a beyond visual range as it is able to hit all enemy moving assets with pin point accuracy despite being invisible.
While trailing enemy fighter plane signatures in the open sky makes it more difficult, it is the speed that kills fast and this enables pilots to ‘look to kill’ their targets with luxury with the advent of modern air-to-air missile (AAM) technologies.
While first generation short range infrared guided AAM relied on the pilot to find and maneuver to attack an often rapidly moving target, 4th and 5th generation short- range AAMs rely on aircraft sensors and advanced helmet mounted displays to target these latest AAMs which usually have much greater range than a pilot’s sight.
In the 1980s, in addition to using the aircraft’s radar, the Soviets introduced more sophisticated optical infrared search and tracking (IRST) systems, which allowed aircraft to turn off emitting radars which in turn could be targeted by opposing electronic sensors and jamming.
Historically, a short-range weapon system was all that was available for air-to-air fighters. As a result, the gun has been a constant in aerial warfare.
However, the advent of air-to-air missile technology and sophisticated airborne radar systems has changed the fighter pilot’s primary weapon of choice to longer range missiles. This trend is evident by highlighting the percentage of gun kills in relation to over all air-to-air kills.
The percentage has shifted from 100 per cent gun kills in WWI and WWII to 0 per cent gun kills in the Persian Gulf War. The improvement in air-to-air missile performance has made the necessity of a gun system suspect.
This advancing trend begs the question; is there a need for a short-range weapon in 21st century air-to-air fighters?
Technology will surely allow for beyond visual range employment, although future missions will be predominantly low intensity conflicts restricted by political rules of engagement. These restrictions will limit the utilization of stealth benefits and missile advantages because fighters will be drawn into the visual arena where a short-range weapon system will be required.
One can have computer sights or anything they like, but one has to go to the enemy on the shortest distance and knock him down from point-blank range. One will get him from in close. At long distance, it is questionable.
The genesis of air-to-air combat occurred in the skies over Europe during World War I. As aerial combat matured, control of the skies became imperative, so that armies were free to maneuver to capture vital positions on the ground.
Aviation technology and armament was primitive and very limited. Air speeds were slow and the only way to destroy an enemy aircraft was at close range with a gun mounted to the aircraft.
This same capability was exhibited in World War II and the Korean War. It was not until the Vietnam War that missile technology made it plausible to shoot down an enemy aircraft beyond visual range (BVR).
Modern technology has advanced so much that missiles can be fired from over 30 miles away, obviously diminishing the need for the classic dogfights. This trend begs the question is there a need for a short-range weapon in 21st Century air-to-air fighters?
The requirement of equipping future fighter jets with a short- range weapon capability needed in visual dogfights.
The requirement to equip 21st Century air-to-air fighters with a short-range weapon system will remain a vital component of air-to-air combat, even though the trend has been to shoot from ever increasing distances.
The historical background of dog fighting, and how it relates to the present day emphasis on visual maneuvering is quite unique. Modern day air-to-air principles and the technological advancements may promote BVR engagements.
As to gunnery passes, the best was when you dived with speed, made one pass, shot an opponent down quickly, and pulled back up. The secret was to do the job in one pass, it could be from the side or from behind.
Aerial combat
An examination of air combats role in history highlights the fact that short-range weapons have been a relative constant in aerial warfare.
The gun has always been a major weapon system in which air-to-air experts have vigorously trained. Aerial combat originated in World War I. Even though it did not play a decisive role in that war, it laid the foundation for a now vital fundamental component of warfare, air superiority.
That degree of dominance in the air battle of one force over another which permits the conduct of operations by the former and its related land, sea, and air forces at a given time and place without prohibitive interference by the opposing force.
In fact, control of the skies allows strategic and tactical bombing, close air support of troops and armor, airborne or surface reinforcement and supply, reconnaissance, and other missions vital to the success of any military operation.
This dictum has remained true for nearly a century and should persevere during the next century. But first, an examination of the past is in order.
During the World War I, the most renowned name in all of air combat is that of Manfred von Richthofen. Germany’s “Red Baron” shot down 80 planes before himself dying in combat.
He achieved his success by following eight commandments of air-to-air tactics devised by Oswald Boelcke. Boelcke was the German Air Service’s leading ace at the time of his death with 40 kills.
One of those commandments was to “fire only at close range and only when your opponent is properly in your sights.”
Today’s guns can reach out to over 6000 feet however, it is still better to shoot at the closest range possible. Shooting at close range however increases the chance of destroying your target by reducing bullet dispersion. Another commandment taught to the German pilots was to always keep your eye on your opponent.
This sounds intuitively obvious, but in a multi-target environment losing sight of the enemy can be fatal. Both of these mandates remain apropos in today’s supersonic, radar and missile environment.
Limited armament and maneuverability drove early air-to-air tactics of World War I aircraft. Most engagements were quick decisive attacks, usually taking less than a minute to complete.
Aircraft were visually acquired within a few miles and attacked by maneuvering behind the airplane and firing at it with the gun. The second leading French ace with 53 kills and a member of the famed French Lafayette Escadrille, Captain Georges Guynemer, said that the first 15 to 20 seconds would decide the fight. He used to dive on his antagonist and hold his fire until the last possible moment.
War tactics
Tactics did not change that much during World War II. The aircraft could fly faster and higher, but the armament was the same, a gun that demanded precise aim under difficult conditions.
Major General Claire Chennault commanded the Flying Tigers in China. Flying the P-40 he devised tactics to engage the more maneuverable Japanese fighters.
He stated, use your speed and diving power to make a pass, shoot and break away.
He also stressed precise gunnery attacks at close range. In The Royal Air Force and the Battle of Britain, Robin Higham remarked that the British aircraft industry was producing some 59 different designs.
The common link amongst these aircraft was the armament - the gun.
Although British pilots flew many different aircraft, employment tactics were similar. They would capitalize on aircraft advantages to maneuver into a favorable position and employ the gun in close combat.
The Korean War introduced the F-86 Sabre as the first jet aircraft capable of speeds in excess of 600 miles per hour and combat ceilings over 35,000 feet. Still, it carried six .50 caliber forward firing machine guns as its only armament.
There were times when over 200 aircraft were airborne at a time; the only way to ascertain an enemy aircraft was with visual identification. Therefore, fratricide was not a major problem because the limited range of the gun forced a visual confrontation.
According to the first jet aircraft ace, Captain James Jabara, air-to-air combat consisted of visually acquiring the enemy, dropping external fuel tanks to increase maneuverability, and then maneuver to get into firing position. After all a fighter is simply an airborne gun platform.
Following the Korean War, technological improvements led to a change in the prevailing theme of air-to-air combat.
In the late 1950’s, at the dawn of the supersonic age, the one-on-one, close-in dogfight was officially decreed obsolete.
The general trend in weapons development was initiated by a new philosophy that future engagements would take place BVR with sophisticated missiles. The US started designing new fighters, such as the F-4 Phantom, without guns.
It seemed obvious that the supersonic speeds of new aircraft would eliminate the need for the “archaic” close-range turning dog fight as it was his philosophy proved to be flawed, as air combat in the Vietnam War revealed.
Missile technology was undependable. Missiles failed about 50 per cent of the time. Missiles had problems detecting, tracking, and fuzing on enemy aircraft.
Shortcomings
Another major shortfall was positively identifying an aircraft as friendly or enemy when outside visual range.
Fighter pilots relied on ground controllers to identify the aircraft for them. Identification was not always accurate because it depended on the reliability of the ground controllers radar and accuracy.
The possibility of shooting down a friendly aircraft was extremely unattractive and absolutely unacceptable. Therefore, there were delays in positively identifying an aircraft, which necessitated a close range visual engagement.
This provided the unenviable situation of being in a position behind an aircraft without the capability to shoot any type of ordnance. Without a gun, F-4 pilots were forced to break off engagements and return to friendly skies.
This trend away from gun production in fighters was reversed in the 1970s. Valuable combat experience had once again demonstrated the value of the gun and the limitations of some of the more exotic weapons.
In fact, the experience in the Vietnam War revealed that technological superiority was not a guarantee for victory.
Although missiles provided an extra dimension, they could not replace the battle proven canon as a vital part of a fighter’s arsenal and a key to survival in a dogfight. As a result, the US started equipping F-4’s with gun pods and later models with internal guns.
Israeli Air Force aerial victories over the Arabs in the Yom Kippur War in 1973 further proved the successful use of the gun.
In fact, about 70 per cent of their air-to-air victories were as a result of canon fire. But it was not until the late 1970s and the introduction of the arguably greatest air-to-air fighter in history, the F-15 Eagle, and the F-16 Fighting Falcon, that technology would make a quantum leap in the conduct of air combat.
The Israelis were the first to test these sophisticated aircraft in combat. They fought the Syrian Air Force in the Bekaa valley in 1982. It was the first time in history that missile kills outnumbered gun kills.
In this war, missiles produced 93 per cent of Israeli kills. They were still mostly fired within visual range, but at greater range than a gun could be employed.
The gun was no longer the primary weapon of choice, but it was used in certain instances.
In the Persian Gulf War, the Coalition Forces assembled in 1991 used the lessons learned from the Israelis over Lebanon 1982.
They attempted to destroy Iraq’s ability to fight a war by precise bombing and control of the skies over Iraq. This minimized the use of ground forces in achieving our objectives, one of which was to drive the Iraqi’s out of Kuwait.
The US Air Force dominated the skies, but the amount of turning fights was limited. There were still many cases where visual fights occurred, but the BVR capability was exploited for the first time in air-to-air combat.
In fact, for the first time in air combat maneuvering, there were no gun kills attributed to air-to-air fighters.
Although missiles achieved all the kills, fighter pilots were provided an extra measure of comfort because they could use the gun, if needed. If missiles did not function properly, the reliable gun was available for close range aerial engagements.
The 20th century air-to-air combat is noteworthy because it depicts the gun as the single constant air-to-air weapon system. This will, in turn, effect future training and weapon acquisition.
The typical aerial engagement has been a visual maneuvering fight between aircraft. It is engrained in the training system used today. All new fighter pilots spend a majority of their training practicing high-g maneuvering, frequently resulting in a gun attempt.
No doubt today’s fighter pilots will train early 21st century F-22 Raptor pilots. They will most likely retain this bias slanted toward visual high-g maneuvering.
The decision to equip the F-22 Raptor with a gun has already been made. However, there are many other variables such as, modern air-to-air principles, Rules of Engagement, stealth technology, and mission-type that will be factored into the decision of how to equip follow-on 21st century fighters.
Improvements
Air-to-air missiles are categorised by the improvements in each generation of weapon systems. The MiG-21 aircraft of the IAF were armed with the first generation K-13 missiles which had an infra-red seeker with a narrow field of vision optimised for interception at high altitude.
However, even a gentle manoeuvre by the target broke the missile lock. The second generation missile had more sensitive seekers and a wider field of vision but the attacking aircraft had still to position itself behind the target.
The third generation brought about a significant change and the “all aspect” missiles appeared on the scene. These missiles had better sensors and allowed the attacker greater freedom to fire with the target “side on” but the field of vision was still very narrow.
The biggest advantage was that the attacking aircraft did not have to be behind the target when launching the missile. While missiles such as the French Matra Magic-2 and the Russian R-60 claimed “all aspect” capability, they fell short of the fighter pilot’s expectations.
The AIM-120, the Russian R-77 and the French MICA dominate the market for active-guided AAMs. In this decade Japan, China and Taiwan have fielded active guided AAMs, with the latter two relying on imported technology.
All active-guided AAM makers have sought to improve their products with better seekers, some using satellite navigation guidance, enhanced electronic counter measures, the addition of data links to provide updated target location data, and better engines to enable longer range.
The US, Russia, Europe, South Africa, and perhaps more recently China, have developed ramjet engine powered AAMs to achieve longer ranges without increasing missile size.
Ramjets also allow the missile to sustain its high speed over most of its range, which significantly expands the “no escape zone” or area within which a target will likely be killed.
The only ramjet powered AAM soon to enter service is the MBDA Meteor, which advertises a 100+km range, and a constant Mach 4+ speed and a “no escape zone” three times that of early AIM-120 AAMs.
The Russian Vympel R-73 was the first of the fourth generation air-to-air missile and provided a quantum jump in capability. It used an advanced cryogenic seeker to improve the “capture” of the target, was resistant to infrared countermeasures by the target aircraft and the agility of the missile was increased by thrust vectoring.
The missile’s field of vision was wider than that of the fighter aircraft’s radar but this dichotomy was corrected by helmet-mounted sights.
With these improvements the fourth generation missiles could be used against low flying targets as they had a “look down, shoot down” capability which cut through the ground clutter.
The R-73 was later upgraded to an improved version, the R-74M which features fully digital and re-programmable systems for greater versatility.
In 1990, after the unification of East and West Germany, the German Air Force found itself with a large stockpile of R-73 missiles.
Performance evaluation in mock combat via-a-vis the Sidewinder AIM-9L showed that the R-73 had been grossly underestimated by the West.
The Russian R-73 was a wake-up call for countries that had no access to Russian technology triggering the development of the Sidewinder AIM-9X, the IRIS-T, MICA-IR and the Python IV missiles.
Sensors
The fifth generation air-to-air missiles have far better seekers that allow the missile to “see” images rather than detect points of infra-red radiation. The new sensors, coupled with digital signal processing, have improved weapons capability and provide lot of benefits.
Sensors can detect aircraft despite infrared counter-measures and it provides enhanced firing range and the ability to track small low flying aircraft and UAVs.
Also, it can give capability to target vulnerable parts of the aircraft instead of merely homing on to the infrared radiation from the engine exhaust.
The IRIS-T made by the German-led consortium, the Russian R-73M2, the Sidewinder AIM-9X, and the Israeli Python 5 missiles fall into this category.
The technological advances of air-to-air missiles in the last 20 years have made them the primary weapons of modern fighter aircraft. Missiles have been designed for specified ranges, for specific guidance systems and even for specific targets such as the AWACS.
Air-to-air missiles can be clubbed into three distinct categories, highly agile short-range Within Visual Range (WVR), less agile but long range Beyond Visual Range (BVR) and very long BVR missiles.
The transition from the third generation to fifth generation missiles has been the result of technological developments which contributed to incremental improvements in capability as under:
Analogue electronics have been replaced by digital software designs giving the missile a “smart’ capability for guidance algorithms, flight path energy management and better techniques for overcoming counter-measures by the target.
Replacement of semi-active guidance systems by autonomous active homing systems can allow fighters to break away earlier but more importantly, permitting engagement of multiple targets.
Seeker technologies have dramatically increased the sensitivity of the missile.
The shift from mechanically oscillating seekers to focal plane arrays and the use of CCD TV imaging devices give missiles the ability to neutralise counter-measures and discern targets amidst the clutter.
This can increase in the flight time of medium range missiles with the introduction of solid propellant ramjets.
The BVR version MICA (EM) RF has an Active Radio Frequency seeker and the WVR close combat missile has a dual waveband Passive Imaging Infra Red seeker.
MBDA claims that both types of missiles are fully BVR capable and can track multiple targets at extended ranges with the two inter-operable guidance systems that are optimised to hamper enemy counter-measures.
Advanced technology
The missile was designed as a multi-aircraft system that could be integrated with any modern fighter and has Lock On Before Launch (LOBL) and Lock On After Launch (LOAL) capability thus giving it a 360-degree envelope.
French pilots who fired the MICA-IR over Libya report that its sensor alone is a useful input to their systems, and its passive seeker with LOAL capability means that it can be fired from Beyond Visual Range at enemy aircraft, without generating any warning to the target from its radar warning receivers.
The Python 4 made by Rafael Advanced Defense Systems, Israel was the first fourth generation missile in production by the West. It was designed to combine the capability of very high sustained G forces during launch and flight with a long duration burn motor to be used in conjunction with a helmet-mounted sight.
The Python 5 uses the same aerodynamic airframe inertial navigation system and rocket motor as the Python 4.
It has BVR and LOAL capability as also all aspect, all direction including “over the shoulder” attack capability. The missile features an advanced electro-optical imaging infra-red seeker which scans the target area for hostile aircraft and then locks on for the terminal phase.
The dual waveband seeker will enables the Python 5 to engage small, low-signature, low-flying targets in adverse weather and cloudy conditions. It has been employed successfully by the Israeli Air Force against UAVs.
The Russian R-77 is an extended medium range air-to-air missile featuring an active radar seeker to engage multiple targets simultaneously. There are other versions of the missile with infrared and passive instead of the active radar seeker.
The missile uses a multi-function Doppler-monopulse active radar seeker. During a short range launch, the missile is launched in a fire-and-forget mode but in a long range launch, the R-77 initially depends on an inertial navigation system with optional in-flight target position updates from the launch aircraft’s sensors.
When the missile is about 20 kms from the target, its radar homing head activates and directs it to the target.
The launch aircraft radar system maintains computed target information in case the target breaks the missiles lock-on. The missile has a solid rocket motor with an air breathing ramjet which can accelerate the missile to a speed of 4.5 Mach with an operating range of up to 140 km.
The unique aerodynamics of the missile gives it a maximum turn rate of up to 150 degrees per second. The missile is used on most of the Russian Air Force fighter aircraft and was designed to counter the AIM-120 AMRAAM.
The Raytheon AIM-120 Advanced Medium Range Air-to-Air Missile was developed as a result of an agreement in the 1980’s between the US and some of the NATO nations to develop air-to-air missiles and share production technology.
The US was to develop the next generation medium range missile to replace the AIM-7 Sparrow and the NATO countries would develop the next generation short range missile to replace the AIM-9 Sidewinder.
However, the agreement fell through and resulted in the US independently developing the AIM-120 and AIM-9X Sidewinder and Germany along with Italy, Sweden, Greece and Norway developing the IRIS-T missile.
The AIM-120 has an all-weather BVR capability and is effective against low flying targets. The missile is guided to a point where the onboard active radar comes on and directs it till impact with the target.
This gives the pilot a ‘fire-and-forget’ capability and the freedom to engage multiple targets or perform evasive manoeuvres while the missile guides itself to the target. The missile has a range of 50 to 75 km and attains a maximum speed of Mach 4. It is carried by the Eurofighter Typhoon.
An agreement signed in the 1980s between the US and some of the NATO countries called upon the UK and Germany to produce the AIM-132, a short-range close combat missile to replace the AIM-9 Sidewinder.
The programme did not get off the ground as the UK and Germany could not come to an agreement on the design of the airframe particularly the lack of thrust vectoring which was considered essential to improve the flight parameters of the missile.
Modern missiles
The UK decided to go its own way in the development of the AIM-132 ASRAAM and Germany decided to design a new missile. In 1995, the Germany-led consortium announced the Infra Red Imaging System Thrust Vector (IRIS-T) programme to develop a short range close combat missile to replace the AIM-9 Sidewinder for the NATO.
Initially the consortium consisted of Germany, Italy, Sweden, Greece, Canada and Norway. Subsequently, Canada pulled out of the programme but Spain joined in 2003. The German Air Force took the first delivery of the IRIS-T missile in 2005.
The missile can be carried by any aircraft that can use the AIM-9 Sidewinder. It is carried by the Eurofighter Typhoon and has been acquired by countries that operate the Lockheed Martin F-16, Boeing F-18 and the Saab Gripen.
The breakdown of the joint development between Germany and the UK to produce the AIM 132 Advanced Short Range air-to-air missile provided the start point for the independent development of this missile by the UK.
The missile is conceptually different from other missiles in that it has been made to engage targets at the maximum range. The missile, also designed to engage the target at close ranges, can be fired in both LOBL as a conventional heat seeker mode or LOAL like a BVR missile.
The missile can also be used as an expendable Infra Red Search and Track device. The ASRAAM can be fired “over the shoulder” under high G and high angle of attack flight conditions as long as the pilot can sight the target through the helmet-mounted sight.
The missile is used by the Royal Air Force and the Royal Australian Air Force. It is reported that the Jaguars of the IAF may be equipped with the ASRAAM as a replacement for the Magic Matra missiles.
China is now catching up with rest of the world. Almost from the beginning the PLA has relied on foreign technology, whether from the United States, Russia, Israel and now South Africa, to develop more modern air-to-air missiles.
From the 1990s to the present period the PLA has purchased thousands of modern Russian AAMs, including the Vympel R-73 short-range AAM, and multiple variants of the semi-active radar and infrared guided Vympel R-27 medium range AAM.
In addition the PLA has purchased about 1,000 of the more modern active radar guided Vympel R-77 medium range AAM.
These missiles almost exclusively arm Sukhoi/KnAAPO made SU-27SK/SU-30MKK/MKK2 fighters or the Shenyang Aircraft Company co-produced version of the Su-27SK called the J-11, or J-11A.
There is also the possibility that the PLA could purchase new Russian very long-range AAMs or develop similar AAMs themselves.
In as much as the PLA is reportedly interested in purchasing some number of the new Russian Sukhoi SU-35 fighter, it may also purchase the unique weapons offered with this fighter, like the 300-400km range Novator K-100/172.
China is developing long-range AAMs like the PL-13 or could purchase the longer range Russian Novator K-100.
