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134-591: Developed originally as a short-range infrared air-to-air missile , the R.550 was meant to be France's lighter short-range missile, replacing the previous heavy R.530 . During a trial on 11 January 1965, a Gloster Meteor of the centre for in-flight trials fired an R.550 Magic and shot down a Nord CT20 target drone. The Magic was then mass-produced from 1967, the Magic was adopted by the French Air Force and Navy for active service. An upgraded version,

268-588: A Greek flag on the east islet on 25 January. To oppose this, on 27 January some Turkish journalists from Hürriyet landed on the islet with a helicopter, lowered the Greek flag and hoisted a Turkish flag , the whole event being broadcast live on Turkish television. On 28 January, the Greek Navy patrol boat Antoniou lowered the Turkish flag and restored the Greek flag, in violation of the political order which

402-524: A Hellenic Navy Bell 212, took off from the Greek frigate Navarino for reconnaissance. The Greek SEALs confirmed the presence of Turkish forces and were ordered to return to the ship where during its return the helicopter crashed over the islets (some speculating due to Turkish fire), but this was concealed by both states to prevent further escalation, although three Greek officers on the helicopter were killed: Christodoulos Karathanasis, Panagiotis Vlahakos, and Ektoras Gialopsos. The immediate military threat

536-498: A Richard single-stage butylene solid-propellant rocket for propulsion, propelling it to speeds up to Mach 3 for the Magic 1, and Mach 2 for the Magic 2. The missile can be outfitted on any aircraft capable of firing the AIM-9 Sidewinder . If the missile misses, it self-destructs after 26 seconds. While the missile was satisfactory as a dogfight missile in the 1980s, it is outdated by today's standards. The Magic 2 replaced

670-625: A better weapon than the Falcon: B models managed a 14% kill ratio, while the much longer-ranged D models managed 19%. Its performance and lower cost led the Air Force to adopt it as well. The first heat-seeker built outside the US was the UK's de Havilland Firestreak . Development began as OR.1056 Red Hawk , but this was considered too advanced, and in 1951 an amended concept was released as OR.1117 and given

804-413: A consistent representation of whatever legal opinions they held with respect to these islands, in the work of their cartographic state agencies. There is also the case of a neighbouring islet, only a few miles from Imia, called Zouka , Dzouka or Topan Adası , which was consistently shown as Turkish in Greek naval maps, but as Greek in Greek topographic maps. When the attention of the Greek government

938-446: A high sensitivity and immunity to noise, or thermal clutter. The missile can attain track through information transmitted (prior to launch) by the aircraft's radar system, helmet mounted target designation system, optoelectronic sighting system, or through merely being pointed at the target and then being uncaged (allowing the seeker head to move freely on the gimbal onboard the missile). The missile has no minimum launch speed, making it

1072-606: A large searchlight fitted with a filter to limit the output to the IR range. This provided enough light to see the target at short range, and Spanner Anlage was fitted to a small number of Messerschmitt Bf 110 and Dornier Do 17 night fighters . These proved largely useless in practice and the pilots complained that the target often only became visible at 200 metres (660 ft), at which point they would have seen it anyway. Only 15 were built and were removed as German airborne radar systems improved though 1942. AEG had been working with

1206-537: A line that runs where Greece today claims the territorial boundary should be, with Imia on the Greek side. Turkey holds that the agreement about the FIR boundaries was not concerned with determining sovereignty, and thus has no bearing on the issue. During and after the crisis of 1996, both sides put a lot of emphasis on previously published maps, which were cited as evidence purportedly showing that their respective views were shared by third parties, or had even been shared by

1340-505: A military helicopter and threw a wreath into the sea around the islets where the three Greek Navy officers were killed in 1996. In December 2016, Turkey's Foreign Minister, Mevlut Cavusoglu , said that the islets were "Turkish soil", while the Greek government responded that "Greece's sovereignty over its islands in the Aegean, including Imia, is indisputable and established by international law." European Commission spokesperson said that

1474-471: A missile airframe and considerable effort remained before an actual weapon would be ready for use. Nevertheless, a summer 1944 report to the German Air Ministry stated that these devices were far better developed than competing systems based on radar or acoustic methods. Aware of the advantages of passive IR homing, the research program started with a number of theoretical studies considering

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1608-404: A month later, on 20 January 1996 when the Greek magazine GRAMMA ran a story, one day after Kostas Simitis was appointed to form a new Greek government as prime minister . The article brought a severe reaction from the Greek press, which was followed by four citizens of the neighboring island of Kalymnos , including the mayor and the owner of a herd of sheep that remained on the islets, hoisting

1742-522: A more conventional hemispherical dome. The first test firing took place in 1955 and it entered service with the Royal Air Force in August 1958. The French R.510 project began later than Firestreak and entered experimental service in 1957, but was quickly replaced by a radar-homing version, the R.511. Neither was very effective and had short range on the order of 3 km. Both were replaced by

1876-525: A number of simple countermeasures, most notably by dropping flares behind the target to provide false heat sources. That works only if the pilot is aware of the missile and deploys the countermeasures on time. The sophistication of modern seekers has rendered these countermeasures increasingly ineffective. The first IR devices were experimented with during World War II . During the war, German engineers were working on heat-seeking missiles and proximity fuses but did not have time to complete development before

2010-619: A number of victories in the middle east and Vietnam. A major upgrade program for the Redeye started in 1967, as the Redeye II. Testing did not begin until 1975 and the first deliveries of the now renamed FIM-92 Stinger began in 1978. An improved rosette seeker was added to the B model in 1983, and several additional upgrades followed. Sent to the Soviet–Afghan War , they claimed a 79% success rate against Soviet helicopters, although this

2144-430: A parliamentary question, Turkish Defence Minister İsmet Yılmaz confirmed that Turkish F-16D Block 40 (s/n 91-0023) of 192 Filo was shot down by a Greek Mirage 2000 with an R.550 Magic II on 8 October 1996 in the disputed airspace near Chios island. The South African Air Force (SAAF) received a number of R.550 missiles before a widespread international arms embargo took effect in 1977. SAAF Mirage F1 aircraft carried

2278-498: A position where the missile would be able to continue tracking even after launch. This problem also led to efforts to make new missiles that would hit their targets even if launched under these less-than-ideal positions. In the UK this led to the SRAAM project, which was ultimately the victim of continually changing requirements. Two US programmes, AIM-82 and AIM-95 Agile , met similar fates. New seeker designs began to appear during

2412-503: A practical detector. Nevertheless, it was used for some time by the US Navy as a secure communications system. In 1930 the introduction of the Ag–O–Cs ( silver – oxygen – cesium ) photomultiplier provided the first practical solution to the detection of IR, combining it with a layer of galena as the photocathode . Amplifying the signal emitted by the galena, the photomultiplier produced

2546-486: A prime candidate for arming helicopters which often fly at significantly lower speeds than fighter fixed-wing platforms. It utilizes a silver-zinc battery to power its electronics. The missile features a 13kg pre-fragmented controlled splinter warhead which makes up 14.6% of the missile's total weight, and uses a proximity fuse for detonation. The warhead is armed 1.8 seconds after launch, making its minimum WEZ (Weapon Employment Zone) 0.3 kilometers (0.18 miles). It utilizes

2680-568: A supersonic version. At this stage the concept was for a defensive weapon fired rearward out of a long tube at the back end of bomber aircraft . In April 1949 the Firebird missile project was cancelled and MX-904 was redirected to be a forward-firing fighter weapon. The first test firings began in 1949, when it was given the designation AAM-A-2 (Air-to-air Missile, Air force, model 2) and the name Falcon. IR and semi-active radar homing (SARH) versions both entered service in 1956, and became known as

2814-447: A transparent plate with a sequence of opaque segments painted on them that was placed in front of the IR detector. The plate spins at a fixed rate, which causes the image of the target to be periodically interrupted, or chopped . The Hamburg system developed during the war is the simplest system, and easiest to understand. Its chopper was painted black on one half with the other half left transparent. For this description we consider

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2948-429: A useful output that could be used for detection of hot objects at long ranges. This sparked developments in a number of nations, notably the UK and Germany where it was seen as a potential solution to the problem of detecting night bombers . In the UK, research was plodding, with even the main research team at Cavendish Labs expressing their desire to work on other projects, especially after it became clear that radar

3082-581: A very desirable device. Kutzscher's team developed a system with the Eletroacustic Company of Kiel known as Hamburg , which was being readied for installation in the Blohm & Voss BV 143 glide bomb to produce an automated fire-and-forget anti-shipping missile. A more advanced version allowed the seeker to be directed off-axis by the bombardier in order to lock on to a target to the sides, without flying directly at it. However, this presented

3216-435: Is 10 acres (4.0 ha). The islands are also referred to as Limnia (Λίμνια) in Greek, or İkizce in Turkish, or as Heipethes in some early-20th century maps. The toponym "Kardak" is believed to come from the Greek "Kar(y)dakia", i.e. "small walnuts", because of their shape. While several other aspects of sovereignty rights in the Aegean , such as the territorial waters and national airspace, had been disputed between

3350-462: Is contained in diplomatic exchanges that have never been disclosed to the public by either of the two parties. Greece also cites as evidence for a former Turkish acceptance of Greek sovereignty the diplomatic procedures around the original delimitation of Flight Information Regions (FIR) within the framework of the ICAO , in 1950. The relevant treaty states that, in the Aegean zone, the boundary between

3484-622: Is debated. The Soviets likewise improved their own versions, introducing the 9K34 Strela-3 in 1974, and the greatly improved dual-frequency 9K38 Igla in 1983, and Igla-S in 2004. The three main materials used in the infrared sensor are lead(II) sulfide (PbS), indium antimonide (InSb) and mercury cadmium telluride (HgCdTe). Older sensors tend to use PbS, newer sensors tend to use InSb or HgCdTe. All perform better when cooled, as they are both more sensitive and able to detect cooler objects. Early infrared seekers were most effective in detecting infrared radiation with shorter wavelengths, such as

3618-436: Is not required, instead, both signals can be extracted from a single photocell with the use of electrical delays or a second reference signal 90 degrees out of phase with the first. This system produces a signal that is sensitive to the angle around the clock face, the bearing , but not the angle between the target and the missile centerline, the angle off (or angle error ). This was not required for anti-ship missiles where

3752-437: Is set too small the image from the target is too small to create a useful signal, while setting it too large makes it inaccurate. For this reason, linear scanners have inherent accuracy limitations. Additionally, the dual reciprocating motion is complex and mechanically unreliable, and generally two separate detectors have to be used. Most early seekers used so-called spin-scan , chopper or reticle seekers. These consisted of

3886-557: The AIM-4 Falcon after 1962. The Falcon was a complex system offering limited performance, especially due to its lack of a proximity fuse, and managed only a 9% kill ratio in 54 firings during Operation Rolling Thunder in the Vietnam War . However, this relatively low success rate must be appreciated in the context of all these kills representing direct hits, something that was not true of every kill by other American AAMs. In

4020-566: The AIM-9M Sidewinder and Stinger use compressed gas like argon to cool their sensors in order to lock onto the target at longer ranges and all aspects. (Some such as the AIM-9J and early-model R-60 used a peltier thermoelectric cooler ). The detector in early seekers was barely directional, accepting light from a very wide field of view (FOV), perhaps 100 degrees across or more. A target located anywhere within that FOV produces

4154-572: The Aegean Sea , situated between the Greek island chain of the Dodecanese and the southwestern mainland coast of Turkey . They are known in Turkey as Kardak . Imia was the object of a military crisis and subsequent dispute over sovereignty between Greece and Turkey in 1996. The Imia dispute is part of the larger Aegean dispute , which also comprises disputes over the continental shelf ,

R.550 Magic - Misplaced Pages Continue

4288-609: The EU is urging Turkey to avoid any kind of “source of friction, threat or action directed against a member-state, which damages good-neighborly relations and the peaceful settlement of disputes.” Tensions around the islets were renewed in January 2017, in light of deterioration of Greco–Turkish relations following Greek refusal to extradite participants of the failed 2016 Turkish coup d'état attempt to Turkey. A Turkish navy missile boat accompanied with two special-forces speedboats entered

4422-469: The Hamburg , an AC signal was generated that matched the rotational frequency of the disk. However, in this case the signal does not turn on and off with angle, but is constantly being triggered very rapidly. This creates a series of pulses that are smoothed out to produce a second AC signal at the same frequency as the test signal, but whose phase is controlled by the actual position of the target relative to

4556-598: The MBDA MICA . 480 Magics were sold to Taiwan and is used by the Republic of China Air Force 's Mirage 2000s . The PL-7 is the Chinese reversed-engineered version of the R.550 Magic 1. The Magic has four fixed fins, four movable fins directly behind the fixed fins, and four notched fins on the tail. As the canards move to guide the missile to the target, small vortices generated by the canards impart roll moments on

4690-542: The Magic 2 , replaced the original model in 1986. In total, 11,300 Magics (7,000 Magic 1s and 4,000 Magic 2s) were produced; they were exported, notably to Iraq and Greece, who used them in combat. The Magic has been used by the Dassault Rafale , Dassault Mirage 2000 , F-16 , Sea Harrier (FRS51), MiG-21 , Super Étendard , Mirage F1 , Mirage 5 , and Mirage III . However, the R.550 is gradually being replaced by

4824-426: The "Sun Tracker", was being developed as a possible guidance system for an intercontinental ballistic missile . Testing this system led to the 1948 Lake Mead Boeing B-29 crash . USAAF project MX-798 was awarded to Hughes Aircraft in 1946 for an infrared tracking missile. The design used a simple reticle seeker and an active system to control roll during flight. This was replaced the next year by MX-904, calling for

4958-484: The 1960s, these islets are shown as Greek territory. After the incident Greece threatened to reopen debate on implementation of an EU customs union accord with Turkey and to block an EU aid package that is part of the accord. Greece mentioned that Turkey broke a commitment under the accord to have amicable ties with EU members. Many EU foreign ministers urged the parties to solve differences amicably. EU members were concerned that Greece's moves against Turkey would violate

5092-410: The 1960s. A new generation developed in the 1970s and the 1980s made great strides and significantly improved their lethality. The latest examples from the 1990s and on have the ability to attack targets out of their field of view (FOV) behind them and even to pick out vehicles on the ground. IR seekers are also the basis for many semi-automatic command to line of sight (SACLOS) weapons. In this use,

5226-480: The 1970s and led to a series of more advanced missiles. A major upgrade to the Sidewinder began, providing it with a seeker that was sensitive enough to track from any angle, giving the missile all aspect capability for the first time. This was combined with a new scanning pattern that helped reject confusing sources (like the sun reflecting off clouds) and improve the guidance towards the target. A small number of

5360-436: The 4.2 micrometre emissions of the carbon dioxide efflux of a jet engine . This made them useful primarily in tail-chase scenarios, where the exhaust was visible and the missile's approach was carrying it toward the aircraft as well. In combat these proved extremely ineffective as pilots attempted to make shots as soon as the seeker saw the target, launching at angles where the target's engines were quickly obscured or flew out of

5494-505: The AD3601 seeker head by the all-aspect AD3633, allowing all-aspect capability (the Magic 1 can only be fired from the rear on the target). The Magic 1 has a transparent dome on its nose, while the Magic 2 is opaque. The Magic 2 also had a reduced amount of time required for the weapon to be prepared for launch. The seeker head has a gimbal limit of 30 degrees, meaning that it can track targets up to 30 degrees off of its boresight. Once launched,

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5628-492: The Athens and Istanbul FIRs was to follow the boundaries of the territorial waters. This implies, according to the Greek view, that both parties at that time were taking for granted that a mutually agreed border did indeed exist, which would contradict the claims of persisting "grey zones" made today by Turkey. The maps of the air zones published after that agreement (e.g. an official map published by Turkey in 1953) do indeed show

5762-495: The Block III version was put into production. The Soviets started development of two almost identical weapons in 1964, Strela-1 and Strela-2. Development of these proceeded much more smoothly, as the 9K32 Strela-2 entered service in 1968 after fewer years of development than the Redeye. Originally a competing design, the 9K31 Strela-1 was instead greatly increased in size for vehicle applications and entered service at around

5896-438: The Greek island Kalymnos , 1.9 nmi (3.5 km; 2.2 mi) southeast of the Greek island of Kalolimnos , 3.8 nmi (7.0 km; 4.4 mi) west of the Turkish peninsula of Bodrum , and 2.2 nmi (4.1 km; 2.5 mi) from the Turkish islet of Çavuş Adası . The islets lie some 300 m (1,000 ft) apart from each other, the eastern one being slightly larger than the western one. Their total surface area

6030-498: The Greek statement misled Greece's own public and distorted the truth “as always”. The next day footage was revealed showing the Turkish patrol boat ramming the Greek boat. Also, Turkey has started to build a watchtower, a facility to accommodate soldiers and a pier on the nearby islet of Çavuş Adası . Thermal cameras will be installed on the island to enable the Turkish Coast Guard to monitor naval activities around

6164-454: The Imia issue in favour of either side. However, both Greek and Turkish public opinion has been eager to observe the stance of foreign governments on the issue, as evidenced through details such as the cartographic treatment of Imia in maps published by state agencies. Particular close attention has been paid in this context to maps published by US government agencies. Shortly after the 1996 crisis,

6298-633: The International Court of Justice. The resolution by the European Parliament entitled "Resolution on the provocative actions and contestation of sovereign rights by Turkey against a Member State of the Union" also stated that Greece's borders were EU borders. In addition, it stated that the islets of Imia belongs to Dodecanese group of islands pursuant to the 1923 , 1932 and 1947 treaties and whereas even on Turkish maps from

6432-466: The Italian government during the 1930s and the Greek government between 1947 and the 1950s had shown itself to be well aware that the 1932 protocol did not provide legal grounds for an exact delimitation of the boundary. Conversely, Greece claims that Turkey, already during the 1930s, had explicitly confirmed to Italy that it considered the 1932 protocol valid and binding. However, most of this evidence

6566-589: The R-73 problem was initially going to be the ASRAAM , a pan-European design that combined the performance of the R-73 with an imaging seeker. In a wide-ranging agreement, the US agreed to adopt ASRAAM for their new short-range missile, while the Europeans would adopt AMRAAM as their medium-range weapon. However, ASRAAM soon ran into intractable delays as each of the member countries decided a different performance metric

6700-491: The R.550 Magic 1 is capable of withstanding 35g's, and the Magic 2 capable of 50g's. On 8 October 1996, 7 months after the escalation over Imia/Kardak a Greek Mirage 2000 fired an R550 Magic II and shot down a Turkish F-16D over the Aegean Sea . The Turkish pilot died, while the co-pilot ejected and was rescued by Greek forces. In August 2012, after the downing of a Turkish RF-4E on the Syrian Coast , in response to

6834-676: The R.550. South African Mirage F1s fired early generation R550 missiles in combat over Angola against MiG-21 and MiG-23 adversaries on a number of occasions. In all but one case, the missiles failed to damage or destroy the MiGs. In an engagement between a Mirage F1CZ and MiG-21 in October 1982, two R.550s were fired by SAAF Major Rankin and one of them damaged the FAPLA MiG-21. The limited performance envelope of early generation R.550s led South Africa to begin developing an indigenous AAM called

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6968-485: The Treaty of Lausanne that are relevant to the Imia and the related "grey-zones" issue, are the following: The problem is because Imia is situated just outside the three-mile boundary of Article 6 and Article 12, but is also not in an obvious, strict sense geographically "dependent" (Article 15) on the larger Dodecanese islands (being still closer to the Turkish mainland than to the next larger island). Greece considers that

7102-613: The Turkish Foreign Ministry notified the Greek authorities that it believed there was a sovereignty issue, and on 29 December it declared the islets Turkish territory. On January 9, Athens rejected the claim, citing the Treaty of Lausanne (1923), the Convention between Italy and Turkey (1932) and the Treaty of Paris (1947). The whole event was barely reported in the media so it was not widely known to public until

7236-512: The US National Imaging and Mapping Agency (NIMA) removed the Greek name Vrakhoi Imia from its maps, adding instead a note saying "Sovereignty undetermined", but in a new edition a few months later, in October 1996, it reverted that move and returned to the Greek name. In addition, the U.S. administration suggested that Turkey's claims be taken to a peaceful resolution according to the international law. The government of Italy ,

7370-497: The V-3 Kukri. Infrared homing Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it seamlessly. Missiles which use infrared seeking are often referred to as "heat-seekers" since infrared is radiated strongly by hot bodies. Many objects such as people, vehicle engines and aircraft generate and emit heat and so are especially visible in

7504-464: The ability to be fired at targets completely out of view of the seeker; after firing the missile would orient itself in the direction indicated by the launcher and then attempt to lock on. When combined with a helmet mounted sight , the missile could be cued and targeted without the launch aircraft first having to point itself at the target. This proved to offer significant advantages in combat, and caused great concern for Western forces. The solution to

7638-618: The account of its former navigation officer it is possible that the islets in question were wrongfully charted as belonging to Turkey by his predecessor. The reason was that during the Second World War boats of a British Special Boat Service flotilla often evaded German patrols by making fast alongside Turkish fishing boats near the islet and convincing the Germans that they were Turkish fishermen in Turkish territory. Out of this experience one officer of HMS Childers, who had served

7772-477: The aircraft and thus produce an ever-increasing signal while the aircraft is providing little or none. Additionally, as the missile approaches the target, smaller changes in relative angle are enough to move it out of this center null area and start causing control inputs again. With a bang-bang controller, such designs tend to begin to overreact during the last moments of the approach, causing large miss distances and demanding large warheads. A great improvement on

7906-410: The angle-off and feed that into the controls as well. This can be accomplished with the same disk and some work on the physical arrangement of the optics. Since the physical distance between the radial bars is larger at the outer position of the disk, the image of the target on the photocell is also larger, and thus has greater output. By arranging the optics so the signal is increasingly cut off closer to

8040-589: The area around the islets on 29 January 2017. According to the statement issued by the Defence Ministry of Greece, they were blocked and warned by Greek coast guard vessels and withdrew from the area after about seven minutes. The Turkish armed forces denied that the ships were blocked but did not otherwise deny the incident; they stated that the mission was a part of an inspection of the Aksaz Naval Base by chief of General Staff Hulusi Akar , who

8174-451: The basic spin-scan concept is the conical scanner or con-scan . In this arrangement, a fixed reticle is placed in front of the detector and both are positioned at the focus point of a small Cassegrain reflector telescope. The secondary mirror of the telescope is pointed slightly off-axis, and spins. This causes the image of the target to be spun around the reticle , instead of the reticle itself spinning. Consider an example system where

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8308-445: The causes for the different sovereignty claims. Bill Clinton said about the crisis: "I thought my aides were joking when they said Turkey and Greece would engage in war over rocks on which none but sheep live. I held phone calls with the leaders of both countries, and convinced them to not go to war over the rocks that inhabited mostly 20 sheep". After 1996, most foreign countries have carefully avoided taking an unequivocal stand on

8442-409: The center of the disk, the resulting output signal varies in amplitude with the angle-off. However, it will also vary in amplitude as the missile approaches the target, so this is not a complete system by itself and some form of automatic gain control is often desired. Spin-scan systems can eliminate the signal from extended sources like sunlight reflecting from clouds or hot desert sand. To do this,

8576-478: The center of the operator's telescope. SACLOS systems of this sort have been used both for anti-tank missiles and surface-to-air missiles , as well as other roles. The infrared sensor package on the tip or head of a heat-seeking missile is known as the seeker head . The NATO brevity code for an air-to-air infrared-guided missile launch is Fox Two . The ability of certain substances to give off electrons when struck by infrared light had been discovered by

8710-401: The centerline it was. Other systems used a second scanning disk with radial slits to provide the same result but from a second output circuit. AEG developed a much more advanced system during the war, and this formed the basis of most post-war experiments. In this case, the disk was pattered with a series of opaque regions, often in a series of radial stripes forming a pizza-slice pattern. Like

8844-477: The code name Blue Jay . Designed as an anti-bomber weapon, the Blue Jay was larger, much heavier and flew faster than its US counterparts, but had about the same range. It had a more advanced seeker, using PbTe and cooled to −180 °C (−292.0 °F) by anhydrous ammonia to improve its performance. One distinguishing feature was its faceted nose cone, which was selected after it was found ice would build up on

8978-401: The control system and commands the missile to turn up. A second cell placed at the 3 o'clock position completes the system. In this case, the switching takes place not at the 9 and 3 o'clock positions, but 12 and 6 o'clock. Considering the same target, in this case, the waveform has just reached its maximum positive point at 12 o'clock when it is switched negative. Following this process around

9112-440: The customs union accord and interfere with developing ties and access to Turkey's market. The United States were also concerned since they were a proponent of Turkish-European links. The French President Jacques Chirac “indicated that the fewer new problems Greece created for EU-Turkish cooperation, the more likely France would be to show solidarity with Greece.” Other European governments reportedly implied that if Greece sabotaged

9246-654: The customs union, then they would stall talks on Cyprus EU membership. Greek Prime Minister said that Greece would cooperate with the EU once Turkey agreed to International Court of Justice jurisdiction, but Turkey must initiate an appeal to the International Court of Justice since it is questioning Greek rights. The Greek opposition criticized the government, for its inability to get more support from Europe, while Turkey sent officials to Europe to explain their views and to counter Greece's attempt to impede Turkish-EU relations and recalled its ambassador from Athens. In October 2019,

9380-401: The detector, or in the case of Madrid , two metal vanes were tilted to block off more or less of the signal. By comparing the time the flash was received to the location of the scanner at that time, the vertical and horizontal angle-off can be determined. However, these seekers also have the major disadvantage that their FOV is determined by the physical size of the slit (or opaque bar). If this

9514-410: The disk spinning clockwise as seen from the sensor; we will call the point in the rotation when the line between the dark and light halves is horizontal and the transparent side is on the top to be the 12 o'clock position. A photocell is positioned behind the disk at the 12 o'clock position. A target is located just above the missile. The sensor begins to see the target when the disk is at 9 o'clock, as

9648-401: The disk. By comparing the phase of the two signals, both the vertical and horizontal correction can be determined from a single signal. A great improvement was made as part of the Sidewinder program, feeding the output to the pilot's headset where it creates a sort of growling sound known as the missile tone that indicates that the target is visible to the seeker. In early systems this signal

9782-406: The distress call. The Turkish captain initially refused the assistance offered, maintaining that he was within Turkish territorial waters. He ultimately accepted being towed to the Turkish port of Güllük by the Greek tugboat. The Greek captain filled in the necessary papers for the salvage fee but the Turkish captain objected, arguing that the freighter had been in Turkish waters. On 27 December,

9916-547: The east islet undetected. On the 30th of January, Turkish and Greek officials gave statements, each insisting on their sovereign rights on Imia. Also, Turkish armored units moved to the Green Line on Cyprus , which caused the alert of the Cypriot National Guard . On 31 January at 1:40 am Turkish special forces SAT Commandos also landed on the west islet escalating the tensions. Around 3 hours later,

10050-438: The emissions from the targets. This led to the practical discovery that the vast majority of the IR output from a piston-engine aircraft was between 3 and 4.5 micrometers. The exhaust was also a strong emitter, but cooled rapidly in the air so that it did not present a false tracking target. Studies were also made on atmospheric attenuation, which demonstrated that air is generally more transparent to IR than visible light, although

10184-433: The entire seeker assembly is mounted on a gimbal system that allows it to track the target through wide angles, and the angle between the seeker and the missile aircraft is used to produce guidance corrections. This gives rise the concepts of instantaneous field of view (IFOV) which is the angle the detector sees, and the overall field of view, also known as the tacking angle or off-boresight capability , which includes

10318-499: The famous Indian polymath Jagadish Chandra Bose in 1901, who saw the effect in galena , known today as lead sulfide, PbS. There was little application at the time, and he allowed his 1904 patent to lapse. In 1917, Theodore Case , as part of his work on what became the Movietone sound system , discovered that a mix of thallium and sulfur was much more sensitive, but was highly unstable electrically and proved to be of little use as

10452-604: The first effective French design, the R.530 , in 1962. The Soviets introduced their first infrared homing missile, the Vympel K-13 in 1961, after reverse engineering a Sidewinder that stuck in the wing of a Chinese MiG-17 in 1958 during the Second Taiwan Strait Crisis . The K-13 was widely exported, and faced its cousin over Vietnam throughout the war. It proved even less reliable than the AIM-9B it

10586-402: The fixed signal is filtered out. A significant problem with the spin-scan system is that the signal when the target is near the center drops to zero. This is because even its small image covers several segments as they narrow at the center, producing a signal similar enough to an extended source that it is filtered out. This makes such seekers extremely sensitive to flares, which move away from

10720-403: The high degree of sensitivity required to lock onto the lower-level signals coming from the front and sides of an aircraft. Background heat from inside the sensor, or the aerodynamically heated sensor window, can overpower the weak signal entering the sensor from the target. ( CCDs in cameras have similar problems; they have much more "noise" at higher temperatures.) Modern all-aspect missiles like

10854-538: The infrared wavelengths of light compared to objects in the background. Infrared seekers are passive devices, which, unlike radar , provide no indication that they are tracking a target. That makes them suitable for sneak attacks during visual encounters or over longer ranges when they are used with a forward looking infrared or similar cueing system. Heat-seekers are extremely effective: 90% of all United States air combat losses between 1984 and 2009 were caused by infrared-homing missiles. They are, however, subject to

10988-406: The islands neighbouring Imia, were ceded to Italy. Later the rights to these islands were ceded by Italy to Greece with the 1947 Treaty of Paris . However, the Treaty of Lausanne does not mention every single small island by name, but treats them summarily. Accordingly, at the heart of the legal issue of Imia is the question whether these islands, by virtue of their geographic situation, fall under

11122-462: The islets. The crucial point of reference for the assessment of the legal status of the islets, acknowledged as such by both sides, is the Peace Treaty of Lausanne of 1923. With this peace treaty, Turkey confirmed large cessions of former Ottoman territory to Greece and Italy which had been de facto under their control since 1911 or 1913. The chain of the Dodecanese islands, which includes

11256-505: The islets. Greek and Turkish officials provided assurances to the United States that their military forces on and arrayed around the islets would be removed, with the U.S. agreeing to monitor the withdrawal. While US engagement was instrumental in defusing the crisis, the fundamental territorial issue has remained unresolved since that time. In January 2016, Greek Defence Minister, Panos Kammenos , flew over eastern Aegean Sea in

11390-413: The location of the target by timing when the image disappeared (AEG) or reappeared (Kepka). The Kepka Madrid system had an instantaneous field of view (IFOV) of about 1.8 degrees and scanned a full 20 degree pattern. Combined with the movement of the entire seeker within the missile, it could track at angles as great as 100 degrees. Rheinmetall-Borsig and another team at AEG produced different variations on

11524-410: The markings on the reticle. At this same instant, a spin-scan system would be producing a constant output in its center null. Flares will still be seen by the con-scan seeker and cause confusion, but they will no longer overwhelm the target signal as it does in the case of spin-scan when the flare leaves the null point. Imia Imia ( Greek : Ίμια ) is a pair of small uninhabited islets in

11658-585: The meaning of the term. Turkey claims that Imia does not fit into the definition stipulated by the Article 14 of the treaty. After the 1996 crisis, the Turkish and Greek governments have made various claims that certain diplomatic exchanges between Turkey and Italy after 1932, and between Turkey and Greece after 1947, provided proof that the respective opponents at that time held legal opinions different from what they claim today, making their present stance inconsistent and untenable. Thus, Turkey has claimed that both

11792-555: The missile's field of view. Such seekers, which are most sensitive to the 3 to 5 micrometre range, are now called single-color seekers. This led to new seekers sensitive to both the exhaust as well as the longer 8 to 13 micrometer wavelength range, which is less absorbed by the atmosphere and thus allows dimmer sources like the fuselage itself to be detected. Such designs are known as "all-aspect" missiles. Modern seekers combine several detectors and are called two-color systems. All-aspect seekers also tend to require cooling to give them

11926-460: The movement of the entire seeker assembly. Since the assembly cannot move instantly, a target moving rapidly across the missile's line of flight may be lost from the IFOV, which gives rise to the concept of a tracking rate , normally expressed in degrees per second. Some of the earliest German seekers used a linear-scan solution, where vertical and horizontal slits were moved back and forth in front of

12060-533: The moving fins. Its diameter is larger than the Sidewinder's, which is 5 inches (127 mm) and a legacy of the US Navy's five-inch rocket, from which the AIM-9 is derived; the larger diameter simplified engineering. It has a Romeo solid-fuel engine , and can engage the target independently from the firing aircraft with its all-aspect cooled infrared homing system. The homing system utilizes sulfur lead granting it

12194-399: The negative voltage portion of its waveform, so the switch inverts this back to positive. When the disk reaches the 9 o'clock position the cell switches again, no longer inverting the signal, which is now entering its positive phase again. The resulting output from this cell is a series of half-sine waves, always positive. This signal is then smoothed out to produce a DC output, which is sent to

12328-474: The next year. Wally Schirra recalls visiting the lab and watching the seeker follow his cigarette. The missile was given the name Sidewinder after a local snake; the name had a second significance as the sidewinder is a pit viper and hunts by heat, and moves in an undulating pattern not unlike the missile. The Sidewinder entered service in 1957, and was widely used during the Vietnam war. It proved to be

12462-492: The opposite side. For instance, a national road map sponsored by the Turkish Ministry of Defense, published just before the crisis, shows Imia (Limnia) as Greek territory. There are other Turkish maps of before 1996 that show Imia as Greek. However, the cartographic evidence of before 1996 is so mixed that the only safe conclusion one can draw from it is that neither of the two governments ever bothered to enforce

12596-564: The original contracting party of the 1932 border protocol, stated on 6 February 1996 that it considered the protocol valid, thus lending support to the Greek position. The European Union backed the Greek side on the Imia Islets dispute, and warned Turkey to refrain from any military operations against Greek sovereignty, and, along with the European Parliament , called Turkey to solve any disputes it has with Greece through

12730-419: The other hand, claims that the criterion of "dependency" must be understood in a narrow sense, and that formations such as Imia may therefore constitute "grey zones" that the treaty has left undecided; or indeed that Turkish sovereignty over them still holds. After the Treaty of Lausanne, a dispute arose between Turkey and Italy over some other small islands, not directly related to the area of Imia. This dispute

12864-472: The period the target is visible to the sensor, the AC waveform is in the positive voltage period, varying from zero to its maximum and back to zero. When the target disappears, the sensor triggers a switch that inverts the output of the AC signal. For instance, when the disk reaches the 3 o'clock position and the target disappears, the switch is triggered. This is the same instant that the original AC waveform begins

12998-487: The presence of water vapour and carbon dioxide produced several sharp drops in transitivity. Finally, they also considered the issue of background sources of IR, including reflections off clouds and similar effects, concluding this was an issue due to the way it changed very strongly across the sky. This research suggested that an IR seeker could home on a three-engine bomber at 5 kilometres (3.1 mi) with an accuracy of about 1 ⁄ 10 degree, making an IR seeker

13132-428: The problem that when the bomb was first released it was traveling too slowly for the aerodynamic surfaces to easily control it, and the target sometimes slipped out from the view of the seeker. A stabilized platform was being developed to address this problem. The company also developed a working IR proximity fuse by placing additional detectors pointing radially outward from the missile centerline. which triggered when

13266-523: The resulting L models were rushed to the UK just prior to their engagement in the Falklands War , where they achieved an 82% kill ratio, and the misses were generally due to the target aircraft flying out of range. The Argentine aircraft, equipped with Sidewinder B and R.550 Magic , could only fire from the rear aspect, which the British pilots simply avoided by always flying directly at them. The L

13400-421: The reticle is modified by making one half of the plate be covered not with stripes but a 50% transmission color. The output from such a system is a sine wave for half of the rotation and a constant signal for the other half. The fixed output varies with the overall illumination of the sky. An extended target that spans several segments, like a cloud, will cause a fixed signal as well, and any signal that approximates

13534-410: The rotation causes a series of chopped-off positive and negative sine waves. When this is passed through the same smoothing system, the output is zero. This means the missile does not have to correct left or right. If the target were to move to the right, for instance, the signal would be increasingly positive from the smoother, indicating increasing corrections to the right. In practice a second photocell

13668-596: The same output signal. Since the goal of the seeker is to bring the target within the lethal radius of its warhead, the detector must be equipped with some system to narrow the FOV to a smaller angle. This is normally accomplished by placing the detector at the focal point of a telescope of some sort. This leads to a problem of conflicting performance requirements. As the FOV is reduced, the seeker becomes more accurate, and this also helps eliminate background sources which helps improve tracking. However, limiting it too much allows

13802-560: The same systems for use on tanks , and deployed a number of models through the war, with limited production of the FG 1250 beginning in 1943. This work culminated in the Zielgerät 1229 Vampir riflescope which was used with the StG 44 assault rifle for night use. The devices mentioned previously were all detectors, not seekers. They either produce a signal indicating the general direction of

13936-541: The same technologies have appeared in the Chinese PL-10 and Israeli Python-5 . Based on the same general principles as the original Sidewinder, in 1955 Convair began studies on a small man-portable missile ( MANPADS ) that would emerge as the FIM-43 Redeye . Entering testing in 1961, the preliminary design proved to have poor performance, and a number of major upgrades followed. It was not until 1968 that

14070-466: The same time. The UK began development of its Blowpipe in 1975, but placed the seeker on the launcher instead of the missile itself. The seeker sensed both the target and the missile and sent corrections to the missile via a radio link. These early weapons proved ineffective, with the Blowpipe failing in almost every combat use, while the Redeye fared somewhat better. The Strela-2 did better and claimed

14204-630: The same year as MX-798, 1946, William B. McLean began studies of a similar concept at the Naval Ordnance Test Station, today known as Naval Air Weapons Station China Lake . He spent three years simply considering various designs, which led to a considerably less complicated design than the Falcon. When his team had a design they believed would be workable, they began trying to fit it to the newly introduced Zuni 5-inch rocket . They presented it in 1951 and it became an official project

14338-487: The scope of the renunciation of sovereignty and the cession to Italy as defined by certain articles of the Treaty of Lausanne. There are also issues relating to the interpretation of a later protocol signed between Italy and Turkey in 1932; regarding certain diplomatic exchanges made between the three parties at various times between 1932 and 1996; and regarding the relevance of actual practice (the factual exercise of sovereignty by either party) prior to 1996. The provisions in

14472-403: The seeker is mounted on a trainable platform on the launcher and the operator keeps it pointed in the general direction of the target manually, often using a small telescope. The seeker does not track the target, but the missile, often aided by flares to provide a clean signal. The same guidance signals are generated and sent to the missile via thin wires or radio signals, guiding the missile into

14606-410: The seeker's mirror is tilted at 5 degrees, and the missile is tracking a target that is currently centered in front of the missile. As the mirror spins, it causes the image of the target to be reflected in the opposite direction, so in this case the image is moving in a circle 5 degrees away from the reticle's centerline. That means that even a centered target is creating a varying signal as it passes over

14740-405: The signal strength began to decrease, which it did when the missile passed the target. There was work on using a single sensor for both tasks instead of two separate ones. Other companies also picked up on the work by Eletroacustic and designed their own scanning methods. AEG and Kepka of Vienna used systems with two movable plates that continually scanned horizontally or vertically, and determined

14874-667: The special boat flotilla, probably charted the Turkish name of these islets, Kardak, and attributed them to Turkey. It is well possible that when the whole Dodecanese was ceded to Greece in 1947, these islets may not have been included in official maps because of the wartime experience of a British naval officer. It appears, in short, that contradictory cartographic evidence in this field has been caused either by wartime mistakes, mere inattention or inadvertent proliferation of previous technical mistakes. It does not necessarily reflect consistent legal opinions or policies of either side. The conflicting cartographic evidence may nevertheless be one of

15008-591: The spinning-disk system. In the post-war era, as the German developments became better known, a variety of research projects began to develop seekers based on the PbS sensor. These were combined with techniques developed during the war to improve accuracy of otherwise inherently inaccurate radar systems, especially the conical scanning system. One such system developed by the US Army Air Force (USAAF), known as

15142-420: The tail fins, which can slow the roll attempted by the missile, or even roll reversal. To prevent interfering moments from the tail, the fins are mounted on bearings allowing the tail fins to spin freely. This is in contrast with the AIM-9, which makes use of "rollerons," which are slipstream driven gyros mounted on the tail fins which stabilize the missile in three axes, and have no fixed fin " canards " forward of

15276-407: The target is moving very slowly relative to the missile and the missile quickly aligns itself to the target. It was not appropriate for air-to-air use where the velocities were greater and smoother control motion was desired. In this case, the system was changed only slightly so the modulating disk was patterned in a cardioid which blanked out the signal for more or less time depending on how far from

15410-483: The target to move out of the FOV and be lost to the seeker. To be effective for guidance to the lethal radius, tracking angles of perhaps one degree are ideal, but to be able to continually track the target safely, FOVs on the order of 10 degrees or more are desired. This situation leads to the use of a number of designs that use a relatively wide FOV to allow easy tracking, and then process the received signal in some way to gain additional accuracy for guidance. Generally,

15544-470: The target, or in the case of later devices, an image. Guidance was entirely manual by an operator looking at the image. There were a number of efforts in Germany during the war to produce a true automatic seeker system, both for anti-aircraft use as well as against ships. These devices were still in development when the war ended; although some were ready for use, there had been no work on integrating them with

15678-582: The territorial waters, the air space , the Flight Information Regions (FIR) and the demilitarization of the Aegean islands. In the aftermath of the Imia crisis, the dispute was also widened, as Turkey began to lay parallel claims to a larger number of other islets in the Aegean. These islands, some of them inhabited, are regarded as indisputably Greek by Greece but as grey zones of undetermined sovereignty by Turkey. The islets lie 5.5 nautical miles (10.2 km; 6.3 mi) east of

15812-570: The time had made a binding commitment to accepting the delimitation as described in the protocol. The Turkish side holds that the protocol is not binding as an international treaty and therefore has no value whatsoever for the resolution of the present dispute. Italy ceded the Dodecanese islands to Greece with the 1947 Treaty of Paris . Article 14 enumerates the islands to be transferred to Greek sovereignty, and states that adjacent islets are to be transferred. The Turkish and Greek sides dispute

15946-414: The transparent portion of the chopper is aligned vertically at the target at 12 o'clock becomes visible. The sensor continues to see the target until the chopper reaches 3 o'clock. A signal generator produces an AC waveform that had the same frequency as the rotational rate of the disk. It is timed so the waveform reaches its maximum possible positive voltage point at the 12 o'clock position. Thus, during

16080-505: The two countries for decades, conflicts over the possession of island territory were unknown until the end of 1995. Until 1985 Turkish hydrographic maps recognised the course of the Greek-Turkish border halfway between Imia and the Turkish coast. The dispute over Imia arose when, on 26 December 1995, the Turkish cargo ship Figen Akat accidentally ran aground on the east islet and had to be salvaged . A Greek tugboat responded to

16214-485: The war ended. Truly practical designs did not become possible until the introduction of conical scanning and miniaturized vacuum tubes during the war. Anti-aircraft IR systems began in earnest in the late 1940s, but the electronics and the entire field of rocketry were so new that they required considerable development before the first examples entered service in the mid-1950s. The early examples had significant limitations and achieved very low success rates in combat during

16348-404: The wording of Articles 12 and 16 together precludes any Turkish claim to territories outside the three-mile boundary once and for all, and that the criterion of "dependency" must be understood in a rather wide sense as covering everything in the whole general area of the Dodecanese outside the three-mile limit, in order to give the provisions of the treaty an inherently consistent meaning. Turkey, on

16482-432: Was based on, with the guidance system and fuse suffering continual failure. As Vietnam revealed the terrible performance of existing missile designs, a number of efforts began to address them. In the US, minor upgrades to the Sidewinder were carried out as soon as possible, but more broadly pilots were taught proper engagement techniques so they would not fire as soon as they heard the missile tone, and would instead move to

16616-464: Was defused primarily by American officials—in particular, US envoy Richard Holbrooke , working by telephone with officials of both sides during the final hours of the crisis. The Greeks and Turks did not speak directly to one another but were responsive to Washington's assistance as an informal intermediary. Agreement was given by both sides to the United States to return to the "status quo ante"—i.e., differing views on sovereignty and no military forces on

16750-414: Was drawn to this fact in 2004, it was quick to admit that Zouka was in fact Turkish and that the attribution to Greece had been a mere technical mistake, since Zouka in fact lies on the Turkish side of the demarcation line of the 1932 protocol. Some of the existing cartographic problems can probably be traced back to a 1946–47 British cartographic survey conducted by the crew of HMS Childers . According to

16884-412: Was fed directly to the control surfaces, causing rapid flicking motions to bring the missile back into alignment, a control system known as "bang-bang". Bang-bang controls are extremely inefficient aerodynamically, especially as the target approaches the centerline and the controls continually flick back and forth with no real effect. This leads to the desire to either smooth out these outputs, or to measure

17018-595: Was going to be a better solution. Nevertheless, Frederick Lindemann , Winston Churchill 's favorite on the Tizard Committee , remained committed to IR and became increasingly obstructionist to the work of the Committee who were otherwise pressing for radar development. Eventually they dissolved the Committee and reformed, leaving Lindemann off the roster, and filling his position with well known radio expert Edward Victor Appleton . In Germany, radar research

17152-460: Was more important. The US eventually bowed out of the program, and instead adapted the new seekers developed for ASRAAM on yet another version of the Sidewinder, the AIM-9X. This so extends its lifetime that it will have been in service for almost a century when the current aircraft leave service. ASRAAM did, eventually, deliver a missile that has been adopted by a number of European forces and many of

17286-531: Was not given nearly the same level of support as in the UK, and competed with IR development throughout the 1930s. IR research was led primarily by Edgar Kutzscher at the University of Berlin working in concert with AEG . By 1940 they had successfully developed one solution; the Spanner Anlage (roughly "Peeping Tom system") consisting of a detector photomultiplier placed in front of the pilot, and

17420-399: Was on board at the time. In February 2018, Greek authorities said that a Turkish coast guard patrol vessel rammed a Greek coast guard boat near the islets. Nobody was injured, but the Greek vessel suffered damage to the stern where the Turkish boat rammed it with its bow. Greece complained to Turkey about the incident. Turkey's Foreign Ministry denied the Turkish vessel was at fault. It said

17554-510: Was only to lower the Turkish flag, resulting in an exchange of fierce statements by the Turkish prime minister Tansu Çiller and the new Greek prime minister Kostas Simitis . Turkish and Greek naval forces were alerted and warships of both countries, both NATO members, sailed to the islets. [REDACTED]   Greece [REDACTED]   Turkey During the crisis, in the night of 28 January, Greek special forces landed secretly on

17688-420: Was settled through a compromise, which was sealed in a bilateral treaty in 1932 at Ankara. As an appendix to that treaty, the two governments formally assured each other that they now considered the whole remaining Dodecanese border between them to be uncontroversial, and appointed a bilateral technical committee to trace its exact delimitation cartographically. The committee produced a technical protocol that

17822-404: Was signed by envoys of the two foreign ministries in the same year. This protocol mentions Imia explicitly, as being on the Italian (i.e. later Greek) side. The protocol itself, according to the present-day Turkish argument, does not bear the formal characteristics of an international treaty. The Greek side now holds that it nevertheless constitutes compelling evidence that the Turkish government of

17956-578: Was so effective that aircraft hurried to add flare countermeasures, which led to another minor upgrade to the M model to better reject flares. The L and M models would go on to be the backbone of Western air forces through the end of the Cold War era. An even larger step was taken by the Soviets with their R-73 , which replaced the K-13 and others with a dramatically improved design. This missile introduced

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