Origins and context
The fact that an Air-Force-instigated program ultimately provided the airborne Navy corps with its first French-made ship-borne jet plane is one of those paradoxes of history.
The Korean War (1950-1953) experience gave Air Force staff and government officials reasons to become concerned with the growing weight and cost of aircraft.
In December 1953, in tandem to its light interceptor program, the Air Force general staff called for a tactical support and fighter aircraft, specilly designed to operate in the vicinity of the front line and, in principle, at low altitude. It was to have a dual mission: to carry out ground attacks and to fight for air superiority, although the former would be its main role. For safety reasons, it was to have twin engines. The Navy also wanted a similar aircraft which could be embarked on its aircraft-carriers.
Two prototypes were ordered, from Dassault and from Breguet alike: two with twin Gabizo jet engines for the Air Force (the Etendard II and the Breguet Br 1100) and two with a single Orpheus engine for the NATO competition (the Etendard VI and the Breguet Br 1001 Taon). On its own initiative, Dassault designed an Etendard IV, based around a Snecma Atar 101 E jet engine; this was also ordered.
To meet the requirements of both French and NATO programs, Dassault kept the aerodynamic configuration of the Mystère XX (the future Super-Mystère) by applying it to smaller aircraft equipped with engines capable of reaching transonic speeds without the use of after-burners.
Thus its was that the Mystère XXII (Etendard II, Mystère XXIV (Etendard IV) and Mystère XXVI (Etendard VI) came to be designed ; they incoporated major advances in high lift devices, allowing for lower take-off and landing speeds.
The Etendard II
The Mystère XXII, renamed Etendard II with its Turboméca Gabizo engines, was a response to the Air Force’s light twin-engine tactical support program. The aerodynamics of the wings from the Super-Mystère B2 were modified to include powerful high-lift devices, making it possible to take off and land on makeshift airfields or aircraft-carriers.
Two prototypes were ordered in November of 1954. Only the first of them actually flew – at Melun-Villaroche, on July 23, 1956, piloted by Paul Boudier. The other, based on a Gabizo reheat turbojet, was not followed through. A third prototype, for the Navy, was envisaged in July 1956, but subsequently abandoned.
The Mystère XXII was finally canceled before the two other engines in the program – the Hispano-Suiza R 80.0 and the Snecma R 105, each with 1,000 kg of thrust – could be completed.
The Etendard IV
The Mystère XXIV, which became the Etendard IV, was the object of a contract awarded to the Mérignac Avions Marcel Dassault corporation on Novembre 1954. A Marine version was envisaged from the outset, taking account of the adaptations required for maritime operation (folding wings, deck landing hooks, reinforced fuselage and landing structures and the accompanying navigation and radar instruments).
With its single 3,500-kg thrust Snecma Atar 101 E engine, the Mystère XXIV flew for the first time at Mérignac on July 24, 1956, piloted by Georges Brian. As with the Mystère XXII, the wing was derived from that of the Super-Mystère B 2. It was heavier and more powerful than its much smaller Etendard II and VI counterparts.
Flight tests confirmed the aircraft’s qualities for ground attack as well as low altitude interception missions, which aroused the interest of the Air Force and Navy. January 18, 1958, saw Pierre Galland on his 241st flight breaking the world record for speed on a 1000 kilometer stretch, flying at an average of 1020 km/h.
At the end of 1957, the Etendard IV to part to the NATO competition but was disqualified because of its Snecma Atar 101 because NATO insisted on the use of the Orpheus jet engine which it financed. There was keen disappointment at the Defense Ministry, which eventually deselected the Etendard IV proposed for the Air Force. Only the year before, an order for 300 aircraft had been envisaged, and then abandoned when the light tactical support program was brought into question by the multipurpose capability expected of the Mirage III.
As for the Navy, as the light twin-engine aircraft program had been held back in check, it came back to the solution proposed by Dassault in July 1954: deriving a seaborne aircraft from the Mystère XXIV (Etendard IV) which had been offered to the Air Force.
Etendard IV M and P
In 1955, the engineering department of aeronautics asked Dassault to redesign the Mystère XXIV (Étendard IV), proposed to the Air Force, to turn it into a ” low-altitude fighter and attack seaborne aircraft”. The seaborne Étendard IV M prototype was a low and middle altitude fighter and attack aircraft, deployable from aircraft-carriers of the Clemenceau class, and fitted with the 4400-kg thrust Snecma Atar 8 jet engine.
The first Étendard IV M flew at Melun-Villaroche on May 21, 1958, with Jean-Marie Saget at the controls. Five pre-production aircraft were manufactured. Its performance and external load capacity made the Étendard IV M an excellent attack aircraft, with a secondary role as an interceptor and aerial combat aircraft, in accordance with the Navy’s specifications. The Navy placed an order for 90, including 30 for photo-reconnaissance (Étendard IV P). The prototype #07 (or Étendard IV P), ordered in September 1959, first flew on November 19, 1960. This version carried 5 OMERA cameras in the fuselage nose, while the ventral bay could accommodate long-focus cameras in lieu of the cannons. It had a nonretractable pole of in-flight refueling.
Between December 9, 1961 and May 26, 1965, the Navy received 69 Étendard IV M and 21 Étendard IV P. For the first time of its history, it reached transonic speeds. Étendard IV M remained in active service in the Navy until July 1991, in a ship-borne fighter school, the Squadron 59 S of Hyères, which they had entered in October 1965. They carried out in all 180 000 hours of flight and 25 300 landings. Étendard IV P remained in active service in the Navy until July 27, 2000. They carried out more than 200 000 hours of flight.
The Mystère XXVI, renamed Etendard VI, spun off the Etendard IV. This single-seater single-engine aircraft was designed especially for ground strikes, and to meet NATO competition targets. NATO awarded a contract to build three prototypes on November 2, 1955. Two of them were finally built.
The first Etendard VI flew on March 15, 1957, out of Melun Villaroche. The second did so on September 14. Gérard Muselli flew them both. Deputy flight test director Jean Robert and test engineer Bernard Sigaud monitored the aircraft.
NATO’s competition was the Dassault team’s first opportunity to work under an international technical committee. The competition took place in Brétigny, from September 16 to October 5, 1957. Dassault pitched the Etendard IV and VI.
NATO financed – and imposed – an Orpheus jet engine, disqualifying the Etendard IV which used a Snecma Atar 101 engine despite its flawless performance.
Political reasons then cut the Orpheus-powered Etendard VI out of the race for the contract which finally went to the Fiat G 91. The disappointed Ministry of Armed Forces finally dropped plans to use the Etendard IV in the Air Force. The previous year’s plans to order 300 units were aborted, as the prospect of the Mirage III’s polyvalence cast a doubt on the usefulness of light tactical-support aircraft.
Characteristics and performance: Etendard II
|Unladen weight||4 200 kg|
|Max. Speed||0.99||Top Mach|
|Type||2 Turboméca Gabizos 2×1100 kgp|
Characteristics and performance: Etendard IV
|Max. Speed||1.25||Top Mach|
|Type||Snecma Atar 101 E 3500 kgp|
Characteristics and performance: Etendard IV M et P
|Unladen weight||5800 kg|
|Max. Speed||1.30||Top mach|
|Max. height||45 000 m|
|Type||1 Snecma Atar 8 C 4 500 kgp|