The Bréguet 763 Deux Ponts was developed in France shortly before the end of the Second World War and would go on the have a notable career as a passenger plane. The aircraft derived its name Deux Ponts from its double-decker cabin design.
Despite its large shape, the 763 established itself as a very safe aircraft that was not involved in any serious incidents. Its flexible design features made it popular with both passengers and Air France from a business standpoint.
Attempts to sell the 763 to foreign markets did not come to fruition due to the emergence of jet airliners. Within France, the 763 also became outdated by the mid-1960s with the introduction of jets and turboprop airliners. However, the 763 also saw service with the French Air Force and proved itself to be a useful transport plane.
Origins & Development
The 763 was conceived by French aerospace and aircraft manufacturer Bréguet Aviation. Before the Second World War, Bréguet had been founded in 1911 by engineer Louis-Charles Breguet.
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The company focused on providing aircraft for the French war effort during the First World War, before switching to building experimental planes during the 1930s interwar period. They also released designs that set several speed and distance records, including the Gyroplane Laboratoire which was an early helicopter design.
As it became apparent that war was likely inevitable by the end of the 1930s, Bréguet designers were again tasked (along with other aircraft manufacturers) to reorientate their production back to military aircraft to meet government specifications on new fighter and bomber proposals.
The German invasion of France put a halt to Bréguet’s design and production of new aircraft, but against the odds, the design teams continued to draw and brainstorm ideas. In 1944, Bréguet came up with an idea for a 100-seat, medium-range commercial airliner that would revive the French airline industry and be the first French postwar civilian aircraft to fly.
Although the 763 did not achieve the feat of being the first, the designers pressed ahead with the concept idea and it evolved into a double-decker aircraft.
The initial design was given the name “Project 761” by Bréguet and work began in the aftermath of the war, with 761 also used to denote the first version of the Deux Ponts.
The aircraft design had a cantilever wing set at mid-height on the fuselage. The plane was also fitted with a retractable tricycle landing gear that had dual-wheel main units.
Bréguet’s design called for readily available engines to streamline the manufacturing process and have the plane ready for an early maiden flight date. As such, power was provided by four 1,580 hp (1,180 kW) SNECMA 14R-24 radial engines.
An elevator was also fitted to enable the crew and passengers to move between the two floors once the aircraft was stationary.
The prototype Bréguet 761 completed its maiden flight on the 15th of February 1949 at the French Air Force base at Vélizy Villacoublay. The first and subsequent test flights all progressed well with no incidents.
As a result, three more pre-production aircraft units were commissioned by Bréguet for demonstration and test purposes. These units were powered by 2,020 horsepower Pratt & Whitney R-2800-B31 radial engines.
The Deux Ponts were also designed to have a maximum takeoff weight of around 50,000 kg.
After all the test flights were concluded as satisfactory and safe, the first units were ordered in 1951 for government and commercial use.
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Bréguet decided to modify the Deux Ponts into the improved 763 variants. The 763 essentially followed the same fuselage design as the 761 prototypes but was fitted with more powerful R-2800 CA18 engine units. The wings were also reinforced and stretched by 3 feet, 11 inches into a wider span.
The 763 completed its maiden flight in July 1951 and was also considered a success in test results.
Bréguet also pitched the new 763 version to potential customers as a flexible aircraft that could alternatively be used for passenger and freight services.
The French government placed an order for 12 763 units in 1951. Six of these units were given to Air France, with the government hoping to revive the civilian airline industry in France, while the other six would be operated by the French Ministry of Aviation for military transport purposes.
A total of 20 763 units were produced and rolled off the production line.
In civilian service, the 763 could take a maximum of up to 107 passengers in its passenger cabins, with standard economy seating for 59 tourist class passengers on the upper deck and 48 premium class passengers on the lower deck.
Alternative configurations of the 763 had the potential to accommodate 135 passengers with narrower seating arrangements.
Air France generally used the 763 on flights to the Mediterranean. One of its main routes was to Algiers in Algeria. On occasion, the Deux Ponts were also used on cross-channel flights to London and domestic routes within France from Paris to the regions.
The 763 also established itself as having an impeccable safety reputation for its time. It never suffered a passenger or crew injury or fatality and was only involved in one minor incident in 1955 with the 763 in question being repaired and returned to service afterwards.
In 1958, Bréguet leased back a 763 unit from Air France and took it on an elaborate sales and publicity tour of North and Latin America. The 763 covered an impressive 25,000 miles during the tour with stopovers in New York, Washington, D.C. and Miami in the United States, before flying down to Bogotá in Colombia, Santiago in Chile and Rio de Janeiro in Brazil.
Despite the 763 tour being an adventure for its crew and showing the plane’s capabilities of operating in different working environments, no potential buyers could be found.
In the United States, jet aircraft were beginning to replace existing but older, more expensive and less reliable piston-driven propeller aircraft in both the military and civilian markets. Initially, jets were generally used for long-haul passenger flights before regional and short-haul jets were built to meet commercial demands.
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In South America, it was noted by national airlines that the 763 would be cheaper to operate than the Douglas DC-4 and DC-3 “Dakota” models that were extensively used on regional civilian flights at the time, but there was a concern that there were neither the infrastructure nor passenger demands for such a large plane.
Although the Deux Ponts proved itself to be a popular and flexible aircraft during its passenger service with Air France, its design was also starting to become obsolete within the French commercial market by the time of the early 1960s.
France had also started producing its jet airlines with the help of British aircraft manufacturer DeHavilland. The jet-powered Sud Aviation Caravelle was introduced to the French commercial market in 1959 and took over many of Air France’s regional to medium haul inter-European flights.
It could carry a similar number of passengers to the 763 but featured greater passenger comfort and could keep up with a faster and more consistent schedule.
Turboprop aircraft such as the Vickers Viscount were also replacing older, Second World War era passenger planes on domestic European routes and could fly just as reliably and quickly as certain jet models while outperforming traditional piston aircraft.
The 763 was withdrawn from passenger service by Air France by the mid-1960s and remained as a cargo transporter until 1971.
The end of the 763’s passenger service did not see the immediate end of the aircraft itself.
France’s Air Force had previously ordered a military transport version of the 763 in 1955, which was built as the 763 Sahara model.
The Sahara variant was designed to feature accommodation for up to 146 fully equipped troops, 85 stretchers and medical attendants or freight which could include military vehicles loaded through a specially fitted large rear opening ramp that was not featured on the commercial edition.
The initial order for the Sahara was cancelled, although Bréguet had already completed four airframes for the air force and these were delivered. Fifteen were eventually ordered for the French Air Force in 1956. These were powered either by Pratt & Whitney R-2800 GB-16 or the CB-17 engines. The military version completed its first flight on the 6th of September 1958.
After the Deux Pont’s withdrawal from the civilian market, Air France transferred their six 763s to the French Air Force in 1964. The three original 761 prototypes also ended in military service.
On the military transport version of the Deux Ponts, the large loading door was fitted at the back and rather curiously, only the top deck had windows for passengers.
The combined purpose-built and converted versions of the 763 gave the French Air Force a flexible and strong transport aircraft, and unlike the civilian routes, it was operated on longer flights to ferry equipment and soldiers abroad when needed.
The 763 was used quite extensively to transport scientists, military personnel and equipment to French nuclear tests taking place in the south Pacific during the 1960s.
The French Air Force retired its fleet of converted and military-produced 763s in 1971.
Out of the 20 Deux Ponts manufactured, three airframe units have survived, one of which is used as a restaurant.
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Proposals were made to manufacture the 763 under license using British-built engines, but these plans did not materialise.
Nonetheless, the 763 stands as a remarkable piece of engineering that proved safe, mass transit was possible and could be revived in the postwar era.
- Crew: 3
- Capacity: 107 passengers
- Length: 28.94 m (94 ft 11 in)
- Wingspan: 42.96 m (140 ft 11 in)
- Height: 9.56 m (31 ft 4 in)
- Empty weight: 32,535 kg (71,727 lb)
- Max takeoff weight: 50,000 kg (110,231 lb)
- Powerplant: 4 × Pratt & Whitney R-2800-CA18 eighteen-cylinder radial engines, 1,800 kW (2,400 hp) each
- Range: 2,290 km (1,420 mi, 1,240 nmi)
- Rate of climb: 5.8 m/s (1,140 ft/min) at sea level