The Latécoère 631 was a civil transatlantic flying boat built by Latécoère, the largest ever built up to its time. The type was not a success, being unreliable and uneconomic to operate. Five of the eleven aircraft built were written off in accidents and one was lost during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

Design and development

The Latécoère 631 was the result of a specification issued in 1936 by the Direction Générale de l'Aviation Civile for a 40-passenger airliner with a range of . The aircraft was ordered in 1938. It was intended that it would be powered by six

Gnome et Rhône Gnome et Rhône was a major French aircraft engine manufacturer. Between 1914 and 1918 they produced 25,000 of their 9-cylinder Delta and Le Rhône 110 hp (81 kW) rotary designs, while another 75,000 were produced by various licen ...

P.18 engines of each. A competitor for this specification was the SNCASE SE.200 Amphitrite. Construction of the aircraft was stopped due to the outbreak of

and was not resumed until after the signing of the Franco-German Armistice. The prototype, registered F-BAHG, first flew on 4 November 1942. It was subsequently confiscated by the Germans, and passed to the

Luftwaffe The ''Luftwaffe'' () was the aerial-warfare branch of the German ''Wehrmacht'' before and during World War II. Germany's military air arms during World War I, the ''Luftstreitkräfte'' of the Imperial Army and the '' Marine-Fliegerabtei ...

, who allocated the codes 61+11. The aircraft was flown to Lake Constance, where it was destroyed in an attack by two

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...

de Havilland Mosquito aircraft on 17 April 1944. SNCASE SE.200 Amphitrite 20+01 was destroyed in the same attack.

History

The second aircraft, F-BANT, first flew on 7 March 1945. It was powered by six

Wright Cyclone Wright Cyclone was the name given to a family of air-cooled radial piston engines designed by the Wright Aeronautical Corporation and used in numerous American aircraft in the 1930s and 1940s. Background The Wright Aeronautical Corporation wa ...

engines of each. Four aircraft were purchased by

Air France Air France (; formally ''Société Air France, S.A.''), stylised as AIRFRANCE, is the flag carrier of France headquartered in Tremblay-en-France. It is a subsidiary of the Air France–KLM Group and a founding member of the SkyTeam global a ...

, and entered service on the

Biscarrosse Biscarrosse (; oc, Biscarròssa) is a commune in the Landes department in Nouvelle-Aquitaine in southwestern France. It is located southwest of Bordeaux, and inland from the seaside resort of Biscarrosse-Plage on the Atlantic coast. Near Bis ...

- Port-Étienne-

Fort de France Fort-de-France (, , ; gcf, label= Martinican Creole, Fodfwans) is a commune and the capital city of Martinique, an overseas department and region of France located in the Caribbean. It is also one of the major cities in the Caribbean. Histo ...

route in July 1947. The aircraft were withdrawn from service in August 1948 following the loss of F-BDRC. SEMAF operated two aircraft until 1950, when the survivor was withdrawn following the loss of F-BANU. The Société France Hydro operated one aircraft until it was lost on 10 September 1955. This was the last flying aircraft, with the remaining four survivors being scrapped. The Latécoère 631 was not a success due to it being unreliable and uneconomic to operate.

Accidents and incidents

;31 October 1945: An

Latécoère 631 (F-BANT) was operating a flight from

Rio de Janeiro Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a ...

, Brazil, to Montevideo, Uruguay, and

Buenos Aires Buenos Aires ( or ; ), officially the Autonomous City of Buenos Aires ( es, link=no, Ciudad Autónoma de Buenos Aires), is the capital and primate city of Argentina. The city is located on the western shore of the Río de la Plata, on South ...

, Argentina, when the propeller of No. 3 engine separated in flight and debris struck the No. 2 engine. A propeller blade sliced a hole in the cabin, killing two passengers. A small fire started and an emergency landing was made in the Laguna de Rocha, Uruguay. The aircraft was subsequently repaired and returned to service. The celebrated poet, diplomat and composer

Vinicius de Moraes Marcus Vinícius da Cruz e Mello Moraes (19 October 1913 – 9 July 1980), better known as Vinícius de Moraes () and nicknamed O Poetinha ("The little poet"), was a Brazilian poet, diplomat, lyricist, essayist, musician, singer, and playwright ...

and writer Rubem Braga, both Brazilians, were on board. ;21 February 1948: A Latécoère 631 (F-BDRD) was on a delivery flight from

Le Havre Le Havre (, ; nrf, Lé Hâvre ) is a port city in the Seine-Maritime department in the Normandy region of northern France. It is situated on the right bank of the estuary of the river Seine on the Channel southwest of the Pays de Caux, very ...

Seine-Maritime Seine-Maritime () is a department of France in the Normandy region of northern France. It is situated on the northern coast of France, at the mouth of the Seine, and includes the cities of Rouen and Le Havre. Until 1955 it was named Seine-Inféri ...

, to

, Landes when it crashed into the

English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" (Cotentinais) or ( Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...

off

Saint-Marcouf, Manche Saint-Marcouf () is a commune in the Manche department in Normandy in north-western France. Second World War During the Second World War, a German coastal battery near the village was bombed but fired on Allied forces landing on Utah Beach on D ...

, in a snowstorm with the loss of all nineteen people on board. The aircraft lacked any

Ice protection system In aeronautics, ice protection systems keep atmospheric moisture from accumulating on aircraft surfaces, such as wings, propellers, rotor blades, engine intakes, and environmental control intakes. Ice buildup can change the shape of airfoils ...

. ;1 August 1948:

Air France Flight 072 On 1 August 1948, Air France Flight 072 went missing over the Atlantic Ocean, presumably killing all 52 people on board. The accident led to the withdrawal of the Latécoère 631 from service by Air France. It was the deadliest aircraft acciden ...

(F-BDRC) ditched in the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

for reasons unknown with the loss of all 52 people on board. The aircraft was operating a flight from Fort-de-France,

Martinique Martinique ( , ; gcf, label=Martinican Creole, Matinik or ; Kalinago: or ) is an island and an overseas department/region and single territorial collectivity of France. An integral part of the French Republic, Martinique is located in ...

, to Port-Étienne (now Nouadhibou), Mauritania. Following this loss, the Latécoère 631 was withdrawn from service by Air France. The

United States Coast Guard The United States Coast Guard (USCG) is the maritime security, search and rescue, and law enforcement service branch of the United States Armed Forces and one of the country's eight uniformed services. The service is a maritime, military, mu ...

ship reported finding debris on August 4 but no sign of survivors. ;28 March 1950: A SEMAF Latécoère 631 (F-WANU) crashed into the Atlantic Ocean off

Cap Ferret Cap Ferret (English: ''Cape Ferret'') is a headland, situated at the south end of the ''commune'' of Lège-Cap-Ferret in the French ''department'' of Gironde and ''region'' of Nouvelle-Aquitaine. The headland takes the form of a spit, which sepa ...

, Gironde, after the aileron control couplings failed due to severe vibration in one of the engines gearboxes with the loss of all twelve people on board. The aircraft was on a test flight from Biscarrosse to determine the cause of the crash of Air France Flight 072. ;10 September 1955: A France-Hydro Latécoère 631 (F-BDRE) suffered wing separation (probably due to windshear) after flying into a tropical storm and crashed 38 mi north of Banyo, French Cameroon, killing all 16 on board. The aircraft was on a flight from Lac Lérè, Chad, to

Douala Douala is the largest city in Cameroon and its economic capital. It is also the capital of Cameroon's Littoral Region. Home to Central Africa's largest port and its major international airport, Douala International Airport (DLA), it is the com ...

French Cameroon French Cameroon or French Cameroons (french: link=no, Cameroun) was a French mandate territory in Central Africa. It now forms part of the independent country of Cameroon. History Beginnings The area of present-day Cameroon came under German ...

(now Cameroon), en route to Biscarrosse for maintenance.