Dassault Mirage IV
The Dassault Mirage IV was a French
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

Jet engine
A jet engine is a reaction engine that discharges a fast moving jet to generate thrust by jet propulsion and in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, pulse jets...

-propelled supersonic strategic bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...

 and deep-reconnaissance aircraft
Reconnaissance aircraft
A reconnaissance aircraft is a manned military aircraft designed, or adapted, to carry out aerial reconnaissance.-History:The majority of World War I aircraft were reconnaissance designs...

. For many years it was a vital part of the nuclear triad
Nuclear triad
A nuclear triad refers to a nuclear arsenal which consists of three components, traditionally strategic bombers, ICBMs and SLBMs. The purpose of having a three-branched nuclear capability is to significantly reduce the possibility that an enemy could destroy all of a nation's nuclear forces in a...

 of the Force de Frappe
Force de frappe
The Force de Frappe is the designation of what used to be a triad of air-, sea- and land-based nuclear weapons intended for dissuasion, and consequential deterrence...

, France's nuclear deterrent striking force.


Work on a supersonic
Supersonic speed is a rate of travel of an object that exceeds the speed of sound . For objects traveling in dry air of a temperature of 20 °C this speed is approximately 343 m/s, 1,125 ft/s, 768 mph or 1,235 km/h. Speeds greater than five times the speed of sound are often...

 bomber able to carry a nuclear bomb started in France in 1956
1956 in aviation
This is a list of aviation-related events from 1956:-February:* February 18 – An engine fire breaks out on a Scottish Airlines Avro York just after takeoff from Malta International Airport, Luqa, Malta...

 as part of the development of France's independent nuclear deterrent. The final specifications, jointly defined by government authorities and Dassault
Dassault Aviation
Dassault Aviation is a French aircraft manufacturer of military, regional and business jets, a subsidiary of Dassault Group.It was founded in 1930 by Marcel Bloch as Société des Avions Marcel Bloch or "MB". After World War II, Marcel Bloch changed his name to Marcel Dassault, and the name of the...

 staff, were approved on 20 March 1957. Dassault's resulting prototype, dubbed Mirage IV 01, looked a lot like the Mirage IIIA, even though it had double the wing surface, two engines instead of one, and twice the unladen weight. The Mirage IV also carried three times more internal fuel than the Mirage III. The aircraft's aerodynamic features were very similar to the III's but required an entirely new structure and layout.

The 01 was an experimental prototype built to explore and solve the problems stemming from prolonged supersonic flight. The sizable technological and operational uncertainties (no plane had yet been found able to cruise at over Mach 1.8 for long periods of time) were only one part of the problem. The weapon-related issues were the other.

It took 18 months to build the 01 in Dassault's Saint-Cloud plant near Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

. In late 1958
1958 in aviation
This is a list of aviation-related events from 1958:- Events :* Gulfstream Aerospace is founded in Savannah, Georgia, in the United States.* The Argentine Navy acquires its first aircraft carrier by purchasing HMS Warrior from the United Kingdom....

, the aircraft was transferred to the Melun-Villaroche flight testing area for finishing touches and ground tests.

Roland Glavany took the 01 into the air for the first time on 17 June 1959. For its third flight, on 20 June 1959, the 01 was authorized to fly over the Paris Air Show
Paris Air Show
The Paris Air Show is the world's oldest and largest air show. Established in 1909, it is currently held every odd year at Le Bourget Airport in north Paris, France...

 at Le Bourget
Le Bourget
Le Bourget is a commune in the northeastern suburbs of Paris, France. It is located from the center of Paris.A very small part of Le Bourget airport lies on the territory of the commune of Le Bourget, which nonetheless gave its name to the airport. Most of the airport lies on the territory of the...

 airport in front of France's President Charles de Gaulle
Charles de Gaulle
Charles André Joseph Marie de Gaulle was a French general and statesman who led the Free French Forces during World War II. He later founded the French Fifth Republic in 1958 and served as its first President from 1959 to 1969....

. On 19 September 1960, René Bigand upped the world record for speed on a 1000-kilometre closed circuit to 1,822 km/h (1,132 mph). Flight 138, on 23 September, corroborated the initial performance and pushed the record on a 500-km closed circuit to an average of 1,972 km/h (1,225 mph), flying between Mach 2.08 and Mach 2.14.

In order to increase range, studies were made of a significantly larger Mirage IVB design, powered by two Pratt & Whitney J75 engines and having a wing area of 120 m² (1,290 sq ft) compared to 70 m² (750 sq ft) of the prototype IV. When this was in turn considered to be too expensive, the medium-sized Mirage IVA, slightly larger than the first prototype, was chosen for three more prototypes to be produced.

The prototype Mirage IVA-02 was flown on 12 October 1961, and was accepted for serial production. The first production Mirage IVA was flown in December 1963
1963 in aviation
This is a list of aviation-related events from 1963:- Events :* Violating a 1959 requirement that all aircraft operating from the aircraft carrier Minas Gerais - which never has operated aircraft - belong to the Brazilian Air Force, the Brazilian Navy establishes an air group of its own for the...

. A series of 62 aircraft were built, and they entered service between 1964
1964 in aviation
For the year see 1964This is a list of aviation-related events from 1964:- Events :* Chilean President Jorge Alessandri grants the Chilean Navy the authority to operate all types of aircraft without restriction...

 and 1968
1968 in aviation
This is a list of aviation-related events from 1968:- Events :* In the 1968 White Paper on Defence, the British Labour government announces that the Royal Navys aircraft carrier force will be phased out as soon as the United Kingdom has completed its withdrawal from Malaysia, Singapore, and the...



The Mirage IV is similar in design layout to the Mirage
Mirage (aircraft)
Mirage is the name of a series of delta-winged fighters and bombers that have been produced by the French aircraft manufacturer Dassault Aviation, flown by the French Air Force, and widely exported to foreign counties.* Dassault Mirage III...

 fighters, featuring a tailless delta wing
Delta wing
The delta wing is a wing planform in the form of a triangle. It is named for its similarity in shape to the Greek uppercase letter delta .-Delta-shaped stabilizers:...

 and a single square-topped vertical fin. It has two SNECMA Atar
The SNECMA Atar is a French axial-flow turbojet engine built by Snecma. It was derived from the German World War II BMW 003 design, but extensively developed though a progression of more powerful models. The name is derived from its original design group, Atelier Technique Aéronautique Rickenbach...

 turbojets in the rear fuselage, with air intakes on both sides of the fuselage that had intake half-cone shock diffusers, known as souris ("mice"), which were moved forward as speed increased to reduce inlet turbulence. It can reach high supersonic speeds: the aircraft is redlined at Mach 2.2
Mach number
Mach number is the speed of an object moving through air, or any other fluid substance, divided by the speed of sound as it is in that substance for its particular physical conditions, including those of temperature and pressure...

 at altitude because of airframe temperature restrictions, although it is capable of higher speeds. The aircraft has 14,000 liters (3,700 gal (US)) of internal fuel, and its engines are quite thirsty, especially in afterburner
Afterburner (engine)
An afterburner is an additional component added to some jet engines, primarily those on military supersonic aircraft. Its purpose is to provide a temporary increase in thrust, both for supersonic flight and for takeoff...


The crew of two (pilot and navigator) are seated in tandem cockpits under separate canopies. A bombing/navigation radar is housed within a radome
A radome is a structural, weatherproof enclosure that protects a microwave or radar antenna. The radome is constructed of material that minimally attenuates the electromagnetic signal transmitted or received by the antenna. In other words, the radome is transparent to radar or radio waves...

 in the fuselage under the intakes, aft of the cockpit. In 1980s, the Martin-Baker Mark 4 ejection seats were also apparently upgraded to Mark 6 standard, providing true "zero-zero (zero speed, zero altitude)" ejection capability. A refueling boom
Aerial refueling
Aerial refueling, also called air refueling, in-flight refueling , air-to-air refueling or tanking, is the process of transferring fuel from one aircraft to another during flight....

 is built into the nose and figures prominently in Mirage IV operations.

The Mirage IV has two pylons under each wing, with the inboard pylons being normally used for large drop tank
Drop tank
In aeronautics, a drop tank is used to describe auxiliary fuel tanks externally carried by aircraft. A drop tank is expendable and often jettisonable...

s of 2,500 liter (660 gal (US)) capacity. The outer pylons carry ECM
Electronic countermeasures
An electronic countermeasure is an electrical or electronic device designed to trick or deceive radar, sonar or other detection systems, like infrared or lasers. It may be used both offensively and defensively to deny targeting information to an enemy...

 and chaff
Chaff (radar countermeasure)
Chaff, originally called Window by the British, and Düppel by the Second World War era German Luftwaffe , is a radar countermeasure in which aircraft or other targets spread a cloud of small, thin pieces of aluminium, metallized glass fibre or plastic, which either appears as a cluster of secondary...

/flare dispenser pods to supplement the internal jamming and countermeasures systems. On current aircraft, these are typically a Barax NG jammer pod under the port wing and a Boz expendables dispenser under the starboard wing. No cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...

 armament was fitted. The early Mirage IVA had a fuselage recess under the engines for a single AN-11
AN-11 bomb
The AN-11 was France's first nuclear weapon, developed to arm the Force de frappe.The AN-11's development began in the late 1950s. An early version was used in France's first nuclear test, on 13 February 1960. The first AN-11 prototype was tested 1 May 1962, and it entered service in 1964.The AN-11...

 or AN-22
AN-22 bomb
The AN-22 was France's second air-dropped nuclear weapon, developed as a replacement for the earlier AN-11 bomb, entering service in 1967. It had a similar 60 to 70 kilotons yield fission warhead to the earlier AN-11, but with enhanced safety features and a parachute retarder to enable it to be...

 nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...

 of 60 kt yield.

From 1972
1972 in aviation
This is a list of aviation-related events from 1972:- Events :* Early in the year, the United States introduces the Walleye II optically guided glide bomb into service, employing it in the Vietnam War. It becomes known as the "Fat Albert."-January:...

 onward, 12 aircraft were also equipped to carry the CT52 reconnaissance
Reconnaissance is the military term for exploring beyond the area occupied by friendly forces to gain information about enemy forces or features of the environment....

 pod in the bomb recess. The CT52 is available in either BA (Basse Altitude, low-level) or HA (Haute Altitude, high-altitude) versions with three or four long-range cameras. A third configuration is an infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...

 line scanner. None of the CT52 has any digital systems, relying on older 'wet' film cameras.

Later Mirage IVP aircraft could be fitted a single centerline pylon for the ASMP
Air-Sol Moyenne Portée
The Air-Sol Moyenne Portée is a French air-launched nuclear missile. Part of the Force de frappe, in French nuclear doctrine it is the last-resort "warning shot" prior to a full-scale employment of strategic nuclear weapons...

 stand-off missile.

The Mirage IVA could theoretically carry up to six large conventional bombs at the cost of drop tanks and ECM pods, but such armament was rarely fitted in practice.

Export hopes

In 1963, the Australian government sought a replacement for the Royal Australian Air Force
Royal Australian Air Force
The Royal Australian Air Force is the air force branch of the Australian Defence Force. The RAAF was formed in March 1921. It continues the traditions of the Australian Flying Corps , which was formed on 22 October 1912. The RAAF has taken part in many of the 20th century's major conflicts...

 fleet of English Electric Canberra
English Electric Canberra
The English Electric Canberra is a first-generation jet-powered light bomber manufactured in large numbers through the 1950s. The Canberra could fly at a higher altitude than any other bomber through the 1950s and set a world altitude record of 70,310 ft in 1957...

 bombers. Dassault proposed a version of the Mirage IVA with Rolls-Royce Avon
Rolls-Royce Avon
|-See also:-Bibliography:* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9-External links:**** a 1955 Flight article on the development of the Avon...

 engines. The IVA was one of five aircraft types short listed but the General Dynamics F-111C
General Dynamics F-111C
The General Dynamics F-111C is a variant of the F-111 Aardvark medium-range interdictor and tactical strike aircraft, developed by General Dynamics to meet Australian requirements. The design was based on the F-111A model but included longer wings and strengthened undercarriage...

 was eventually selected.

In 1965, when the British Government
Labour Party (UK)
The Labour Party is a centre-left democratic socialist party in the United Kingdom. It surpassed the Liberal Party in general elections during the early 1920s, forming minority governments under Ramsay MacDonald in 1924 and 1929-1931. The party was in a wartime coalition from 1940 to 1945, after...

 cancelled the BAC TSR-2
The British Aircraft Corporation TSR-2 was a cancelled Cold War strike and reconnaissance aircraft developed by the British Aircraft Corporation for the Royal Air Force in the late 1950s and early 1960s...

 reconnaissance-strike aircraft, Dassault proposed a modified version of the Mirage IV as a replacement. The modified aircraft, known as the Mirage IV* was to use more powerful Rolls-Royce Spey turbofan
The turbofan is a type of airbreathing jet engine that is widely used for aircraft propulsion. A turbofan combines two types of engines, the turbo portion which is a conventional gas turbine engine, and the fan, a propeller-like ducted fan...

 engines and avionics planned for the TSR-2. While the IV* was claimed to meet most of the RAFs requirements, and to be £1 million cheaper than the American F-111
General Dynamics F-111
The General Dynamics F-111 "Aardvark" was a medium-range interdictor and tactical strike aircraft that also filled the roles of strategic bomber, reconnaissance, and electronic warfare in its various versions. Developed in the 1960s by General Dynamics, it first entered service in 1967 with the...

, the F-111 was preferred (only to be cancelled in turn) and the Spey-engined Mirage abandoned.

Operational history

In February 1964 deliveries of the Mirage IV to the French Air Force started, with the first French strategic bombing
Strategic bombing
Strategic bombing is a military strategy used in a total war with the goal of defeating an enemy nation-state by destroying its economic ability and public will to wage war rather than destroying its land or naval forces...

 squadron being declared operational on 1 October that year. The Mirage IV bomber force, when fully built up, consisted of three wings. These wings were each divided into three bomber squadrons, each with four Mirage IVs, each deployed at a different base to minimise the potential for an enemy strike to knock out the entire bomber force. These squadrons were:
  • 1/91 'Gascogne' based at Mont de Marsan
  • 2/91 'Bretagne' based at Cazaux
    Cazaux is a commune of the Ariège department in southwestern France....

  • 1/93 'Guyenne' based at Istres
    Istres is a commune in southern France, some 60 km northwest of Marseille. It is in the Provence-Alpes-Côte d'Azur region, in the Bouches-du-Rhône department, of which it is a subprefecture...

  • 2/93 'Cevennes' based at Orange
    Orange, Vaucluse
    Orange is a commune in the Vaucluse department in the Provence-Alpes-Côte d'Azur region in southeastern France.It has a primarily agricultural economy...

  • 1/94 'Bourbonnais' based at Avord
    Avord is a commune in the Cher department in the Centre region of France.-Geography:A farming area comprising the village and several hamlets situated by the banks of the river Yèvre, some east of Bourges at the junction of the D976 with the D36 and the D71 roads...

  • 2/94 'Marne' based at St-Dizier
  • 3/94 'Arbois' based at Luxeuil
  • 3/91 'Beauvaisis' based at Creil
    Creil is a large town in northern France. It is designated municipally as a commune within the département of Oise.-History:Archaeological remains in the area include a Neolithic site, as well as a late Iron Age necropolis, perhaps belonging to a Gaulish fortress or protected camp.The city itself...

  • 3/93 'Sambre' based at Cambrai
    Cambrai is a commune in the Nord department in northern France. It is a sub-prefecture of the department.Cambrai is the seat of an archdiocese whose jurisdiction was immense during the Middle Ages. The territory of the Bishopric of Cambrai, roughly coinciding with the shire of Brabant, included...

After establishment of its own deterrent force (the Force de Dissuassion, more commonly known as the Force de frappe, France quit the military command structure of NATO in 1966
1966 in aviation
This is a list of aviation-related events from 1966:-January:* The United States Armys helicopter assault-oriented 1st Cavalry Division begins Operation Matador to destroy North Vietnamese Army forces in Pleiku and Kon Tum Province, South Vietnam....


The primary objectives of the Mirage IVA force were major Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 cities and bases. With aerial refueling
Aerial refueling
Aerial refueling, also called air refueling, in-flight refueling , air-to-air refueling or tanking, is the process of transferring fuel from one aircraft to another during flight....

, the plane was able to attack Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...

, Murmansk
Murmansk is a city and the administrative center of Murmansk Oblast, Russia. It serves as a seaport and is located in the extreme northwest part of Russia, on the Kola Bay, from the Barents Sea on the northern shore of the Kola Peninsula, not far from Russia's borders with Norway and Finland...

 or Ukrainian
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

 cities from French bases. In order to refuel the Mirage IVA fleet, France purchased a number of U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 C-135F tankers. Mirage IVAs also often operated in pairs, with one aircraft carrying a weapon and the other carrying fuel tanks and a buddy refueling pack allowing it to refuel its mate en route to the target. Even so, some sources state that some of the mission profiles envisioned were actually one-way, with the crew having no chance of returning after bombing a Soviet city.

Initially, the basic attack flight profile was "high-high-high" at a speed of Mach 1.85, engaging targets up to a maximum radius of 3,500 km (2,175 mi). In the late 1960s, when the threat of surface-to-air missile
Surface-to-air missile
A surface-to-air missile or ground-to-air missile is a missile designed to be launched from the ground to destroy aircraft or other missiles...

 defences made high-altitude flight too hazardous, the Mirage IVA was modified for low-altitude penetration. Flying low, the maximum attack speed was reduced to 1,100 km/h (680 mph) and the combat radius was also decreased.

By the 1970s it was clear that vulnerability of the Mirage IV to air defences (even in low-level flight) made the delivery of gravity bomb
Gravity bomb
An unguided bomb, also known as a free-fall bomb, gravity bomb, dumb bomb, or iron bomb, is a conventional aircraft-delivered bomb that does not contain a guidance system and hence, simply follows a ballistic trajectory....

s like the AN-11 or AN-22 impractical. As more of the deterrent role was passed to land-based IRBMs and submarine-based missiles, one wing of Mirage IVs was stood down in 1976, while in 1979, in response, to the decreasing effectiveness of the free-fall bombs used by both its strategic and tactical nuclear forces, the French commenced development of the ASMP
Air-Sol Moyenne Portée
The Air-Sol Moyenne Portée is a French air-launched nuclear missile. Part of the Force de frappe, in French nuclear doctrine it is the last-resort "warning shot" prior to a full-scale employment of strategic nuclear weapons...

 stand-off missile, with a range of up to 400 km (250 mi) and a single 150 or 300 kt nuclear warhead. Eighteen Mirage IVAs were modified to carry the new weapon instead of bombs and received the new designation Mirage IVP (Penetration). The first Mirage IVP flew on 12 October 1982 and entered service on 1 May 1986. This variant could carry either a single missile or a reconnaissance pod on the centerline. When the Mirage IVP entered service with EB 1/91 and EB 2/91 (six bombers per squadron) all other Mirage IVA squadrons were disbanded. The aircraft were conserved and stored at Bordeaux Mérignac where they were demolished in 1997.

In 1996
1996 in aviation
This is a list of aviation-related events from 1996:-February:* February 6 – Turkish charter company Birgenair Flight 301 crashes in Puerto Plata, Dominican Republic after takeoff...

 the Mirage IVP's nuclear mission was also transferred to the Mirage 2000N. EB 2/91 was disbanded and EB 1/91 was redesignated Escadron de Reconnaissance Stratégique (Strategic Reconnaissance Squadron), using the 12 remaining Mirage IVPs. In the reconnaissance
Reconnaissance is the military term for exploring beyond the area occupied by friendly forces to gain information about enemy forces or features of the environment....

 role, the Mirage IVP has seen service over Bosnia
Bosnia and Herzegovina
Bosnia and Herzegovina , sometimes called Bosnia-Herzegovina or simply Bosnia, is a country in Southern Europe, on the Balkan Peninsula. Bordered by Croatia to the north, west and south, Serbia to the east, and Montenegro to the southeast, Bosnia and Herzegovina is almost landlocked, except for the...

, Iraq
Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert....

, Kosovo
Kosovo is a region in southeastern Europe. Part of the Ottoman Empire for more than five centuries, later the Autonomous Province of Kosovo and Metohija within Serbia...

, and Afghanistan
Afghanistan , officially the Islamic Republic of Afghanistan, is a landlocked country located in the centre of Asia, forming South Asia, Central Asia and the Middle East. With a population of about 29 million, it has an area of , making it the 42nd most populous and 41st largest nation in the world...


ES 1/91 Gascogne's surviving Mirage IVPs were retired in 2005
2005 in aviation
This is a list of aviation-related events from 2005:-January:*January 18 - The world's largest passenger plane, the Airbus A380, gets unveiled in an elaborate ceremony in France....

 and are conserved and stored at the Centre d'Instruction Forces Aériennes Stratégiques (CIFAS) at Bordeaux Mérignac. They were scheduled to be immediately replaced by Mirage 2000N aircraft fitted with the new PRNG (Pod de Reconnaissance Nouvelle Génération, New Generation Reconnaissance Pod) system with digital camera
Digital camera
A digital camera is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. It is the main device used in the field of digital photography...

 equipment. However, the reconnaissance-configured 2000Ns will not be ready until 2007, so the Armée de l'Air's Mirage F1CRs are carrying out all aerial reconnaissance
Aerial reconnaissance
Aerial reconnaissance is reconnaissance that is conducted using unmanned aerial vehicles or reconnaissance aircraft. Their roles are to collect imagery intelligence, signals intelligence and measurement and signature intelligence...

 missions in the meantime.

Note, however, that 16 Mirage IV airframes are visible via Google Earth at the Châteaudun Air Base
Châteaudun Air Base
Châteaudun Air Base is a French Air Force base. The base is located approximately southeast of Châteaudun; about southwest of Paris.The base is primarily used for aircraft storage and ferrying them to other squadrons of the Air Force. EAA 601 is assigned to perform this mission...

 (photo date 2007).

The Mirage IV had been popular with its crews, which find it enjoyable to fly despite its antiquated systems and generally uncomfortable cockpit, and it requires surprisingly little maintenance considering its age and complexity.

Aircraft on display

  • 16 is on display at St Dizier airfield.
  • 43 is on display at Mont-de-Marsan airbase.
  • 62 is on display at the Musée de l'Air et de l'Espace
    Musée de l'Air et de l'Espace
    The French Air and Space Museum is a French museum, located in the south-eastern edge of Le Bourget Airport, north of Paris, and in the commune of Le Bourget. It was created in 1919 from a proposition of Albert Caquot .-Description:Occupying over of land and hangars, it is one of the oldest...

     at Paris-Le Bourget.

Specifications (Mirage IVA)

See also

External links

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