On October 12, 1951 the Comité du Matériel Civil (commercial aircraft authority) published a specification for a medium range aircraft, which was later sent to the industry by the Direction Technique et Industrielle. This called for an aircraft carrying 55 to 65 passengers and 1000kg of cargo on routes up to 2000km with a cruise speed about 600km/h. The type and number of engines wasn't specified. Various design studies for aircraft in this category had been underway since 1946 by several of the leading French aircraft manufacturing organisations, but none had the financial power to start construction. for financial reasons none of these had reached the stage of actual construction.
Response from the French industry was strong, with every major manufacturer sending in at least one proposal, with a total of 20 different designs were received. Most of the proposals used all-turbojet power, although Breguet entered a number of designs for both turbojet and turboprop types; among these was one for an Atar-powered tri-jet to be developed in association with the SNCA du Nord and a turbroprop type, all known as Br. 978. Hurel-Dubois entered several turobprop designs based on a narrow fuselage and shoulder mounted wing similar to many regional propliners. Proposals from the SNCA du Sud-Ouest included the .O.60 with two Rolls-Royce Avon RA.7 engines, with two smaller Turbomeca Marbores as auxiliaries. SNCA du Sud-Est returned a number of designs from the X-200 to X-210, all of them pure-jet.
After studing the various entries, the Comité du Matériel Civil cut the list to three entrents on March 28, 1952: the four-engined Avon/Marbore' S.0.60, the twin-Avon Hurel-Dubois project, and the Sud-Est X-210. Rolls-Royce started offering a new version of the Avon that could develop 9,000lb thrust, making the auxiliary engines on the SO.60 and the third engine on the X-210 unnessesary. The Comite requested SNCASE re-submit the X-210 as a twin-Avon design, and when they did so they decided not to move the remaining engines from the rear-mounted position instead of placing them under the wing as the other designs did (which is slightly lighter because they can be mounted on the spar). This turned out to be a benefit to the design, as the cabin noise was greatly reduced.
The revised X-210 design with twin Avons was re-submitted to the SGACC in July 1952, and only two months later the SNCASE received official notification that its design had been accepted. On July 6, 1953 the SGACC ordered two prototypes and two static airframes for fatigue testing. Sud's design licensed several fuselage features from De Havilland, a company Sud had dealings with for several earlier designs. The nose area and cockpit layout were both taken directly from the Comet, while the rest of the plane was locally designed.
The first prototype was rolled out on April 21, 1955, and flew on May 27th, the second followed a year later on May 6th, 1956. The first prototype had a cargo door on the lower left side of the fuselage, but this was removed the second prototype for an all-seating arrangement. The first order was from Air France in 1956, followed by SAS in 1957. That year Sud-Est merged with Sud-Ouest to become Sud Aviation, but the original SE naming was retained. More orders followed, mainly triggered by presentations on airshows and demonstrations to potential customers. The Caravelle was certified in May 1959 and entered shortly after service with SAS and AF.
Several models were produced over the lifetime of the production run, as the power of the available engines grew and allowed for higher takeoff weights. By this time most of Sud Aviation's design department turned to a supersonic transport of the same general size and range as the Caravelle, naturally naming it the Super-Caravelle, however this work would later be merged with similar work at the Bristol Aeroplane Company to produce the Concorde.
In total 279 Caravelles of all types were build, with Sud Aviation's break-even point at the 200 mark. The Caravelle was thus the first airliner design to make a clear profit, something that would not be matched again until the 1970s.
Caravelle I
Similar to the original protoypes, 19 sold to Air France and SAS.
Caravelle IA
13 built. They were 50cm longer than the prototype, had higher weights and bigger engines.
Caravelle III
Same length than the IA, but again higher weights and bigger engines. The Series III was the best-selling Caravelle with 78 built. Out of the 32 Series I, 31 were upgraded to Series III specs.
Caravelle VI-N
Similar to the III, but with even-larger engines. Out of the 78 Series III, 5 were upgraded to Series VI N. Launched in 1960, 53 built.
Caravelle VI-R
Similar to the VI-N, but added thrust reversers and spoilers. Launched in 1961, 56 built, 20 for United Airlines.
Caravelle VII
This was a modified Series III which was purchased by General Electric and equipped with GE CJ-805 engines. It would form the basis for later sales into the US.
Caravelle 10A
Based on the Series VII, but intended for the US market with an initial order of 20 by TWA. The 10A was 1 meter longer than the Series VI, with the windows were located 20cm higher on the fuselage and an APU was installed in the rear. A modified wing with improved flaps was also included to meet FAA requirements. However TWA later cancelled its order due to financial problems, and by the time they were ready to purchase new designs they have the Douglas DC-9 to select. Only a single Caravelle 10A was ever built.
Caravelle 10B
Based on the Series 10A, but mounting Pratt & Whitney JT8D engines instead of the General Electric models. The 10B first flew in 1964 and was produced as a run of 22 aircraft.
Caravelle 10R
A combination of the 10B's engines on the Series VI-R fuselage, creating a smaller but higher powered plane. 20 built starting in 1965.
Caravelle 11R
The 11R was a Series 10R with the cargo hold from the original prototype re-introduced. This enabled it to carry a mixed load of passengers and cargo. First flight of the series 11R was in 1967 a total of 6 planes was built.
Caravelle 12 (Super-Caravelle)
The Series 12 was a 10B with a noticably longer fuselage, stretched by 3.2 meters, and a newer uprated version of the JT8D engines. This allowed for up to 128 passengers over a reduced range. The 12 was aimed primarily at the charter market, produced to 12 examples starting in 1972. By this point the original SST Super-Caravelle was in production as the Concorde, and the 12 was often referred to by this name. Series 12's flew in Europe until October 1996, and five continue to fly in Africa to this day (2002).Models