The Breguet XIV (in contemporary practice) or Breguet 14 was a French biplane bomber and reconnaissance aircraft of World War I. It was built in very large numbers and production continued for many years after the end of the war.
The Breguet 14 was among the first mass-produced aircraft to use large amounts of aluminium, rather than wood or steel, in its structure. This allowed the airframe to be both lighter and stronger, in turn making the aircraft fast and agile and it was able to outrun some contemporary fighters.
The Breguet 14 was designed by aviation pioneer and aeronautical engineer Louis Breguet.[1] Breguet had already built a reputation for producing capable aircraft and for having innovative ideas, including the use of metal in aircraft construction. The outbreak of the First World War in 1914 led to Breguet-built aircraft being ordered by the military air services of several Triple Entente nations. He temporarily abandoned the preferred tractor configuration for a pusher design to satisfy the French general staff, who sought a clear forward view for the observer.[2] In spite of the French official preference for pushers, Breguet remained a proponent of tractor aircraft.[3] In June 1916, he began a new design for a military two-seater, the Breguet AV. The French Army's Section Technique de l' Aéronautique (STAé) recommended that Breguet use the Hispano-Suiza 8A V-8 engine of . Breguet determined that the Hispano-Suiza lacked sufficient power, and instead chose the Renault V-12 engine previously used in the Breguet Type V.[4]
Two variants of the Breguet AV (Type XIII and Type XIV to the French authorities) were built. Both had a boxy shape that was complemented by a rectangular frontal radiator and the unusual negative or back stagger of its wings.[4] It possessed a sturdy undercarriage, along with ailerons on the upper wing only. The lower wing featured flaps along the entire trailing edges, that were forced into their raised position by the air, as the aircraft accelerated to its normal speed, being restricted from moving freely by a set of 12 adjustable rubber bungee cords.[5]
The airframe's structure was constructed primarily of duralumin, an aluminium alloy which had been invented in Germany by Alfred Wilm only a decade previously. Many sections, such as the duralumin longerons and spacers, were attached using welded steel-tube fittings and braced using piano wire. The wing spars were of rectangular duralumin tubes with either oak or ash shims at the attachment points and wrapped in a sheet steel sheath.[4] The wooden box ribs had fretted plywood webs and ash flanges. The tail unit was built up from welded steel tube, while the elevators featured large horn balances.[4] French officials were initially wary of the Type XIV's innovative materials due to a lack of experience with them.
Louis Breguet took the prototype into the air for the first time on 21 November 1916.[6] In November 1916, the S.T.Aé. had issued requirements for four new aircraft types, and Breguet submitted the XIV for two of those - reconnaissance and bomber.[6]
The prototype was passed to the S.T.Aé on 11 January 1917 for trials and was accepted to fill both roles. The report issued on 7 February 1917 from the trials stated that the prototype had attained a speed of at an altitude of .[6] On 22 February 1917, Breguet asked the S.T.Aé about initiating production and informed them on 2 March that jigs were ready.[6] On 6 March 1917, the first official production order was received by Breguet, calling for 150 Breguet XIV A.2 reconnaissance aircraft and an additional order for 100 XIV B.2 bombers was received on 4 April.[6] The A.2 was equipped with several cameras, while some also had radios. The lower wing of the 14 B.2 was fitted with Michelin-built bomb racks for thirty-two bombs. To avoid the bomb racks jamming the flaps, a forward extension of the wings was added, while transparent panels were added to the sides of the fuselage to aid in the use of the bomb sight.[7]
By mid-1917, the French authorities ordered a substantial increase in production.[8] Various other companies were contracted to manufacture the type.[6] On 25 April, French aviation company Darracq was requested to manufacture 330 aircraft. On 8 June, 50 were ordered from Farman and on 18 June, Paul Schmitt was issued a contract to produce 200 aircraft.[6] Some of the contractors were unable to commence quantity production of the Breguet 14 until 1918.[7] Following the war, some aircraft were constructed in French military workshops in Indo-China, although these are likely to have been reliant on imported parts.
As an insurance against engine shortages, alternatives to the standard Renault powerplant were installed, both for experimental purposes and in production quantities. Aside from some used in France, many of the Belgian and American Breguet 14s were powered with the Fiat A.12 engine.[9] An improved model of the standard engine, the Renault 12Ff, appeared in Summer 1918 and was used on some late production aircraft. Another engine adopted was built by French automotive company Lorraine-Dietrich, which was lighter but produced less power than the Renault unit. A number of late production B.2 models were equipped with the American Liberty engine. To distinguish these aircraft, they were designated Breguet XIV B.2 L.[10]
Other minor variants of the Breguet 14 were flown in small numbers during the Great War; these included the XIV B.1 (Bombardement) long-range single-seat bomber, the XIV GR.2 (Grande Raid) long-range reconnaissance/bomber, the XIV H (Hydro) floatplane, the XIV S (Sanitaire) air ambulance and the XIV Et.2 (Ecole) trainer.[11] Later variants, such as the XIVbis A.2 and XIVbis B.2, featured improved wings. An variant equipped with enlarged wings was produced as the XVI Bn.2 (Bombardement de nuit) night bomber. Further derivatives of the aircraft included the XVII C.2 (Chasse) two-seat fighter, which would only be built in small numbers due to the end of the war.[12] Production of the Breguet 14 would continue long after the end of the war, only ending in 1926.[13]
The Breguet 14 was used in large numbers from May 1917 onwards, and at its peak equipped at least 71 escadrilles, and was deployed on both the Western Front, where it participated in number major actions in which it typically acquitted itself well,[7] and in the east, on the Italian front.
For its actions during the Battle of the Lys, the Section Artillerie Lourde, equipped with the type, received a citation and was further lauded for its actions during the Allied counter-attack to the German spring offensive. On 9 July 1918, Capitaine Paul-Louise Weiller shot down two enemy aircraft during one sortie while flying the type.[7]
Following its introduction by the French, during 1918, the Breguet 14 was also ordered by the Belgian Army (40 aircraft) and the United States Army Air Service (over 600 aircraft).[14] Around half the Belgian and U.S. aircraft were fitted with Fiat A.12 engines due to shortages of the original Renault 12F. Prior to the Armistice of 11 November 1918, the Breguet 14 was typically assigned to serve in both reconnaissance and bombing roles. By the end of the conflict, the type was reportedly responsible for having dropped over of bombs.[15]
A Breguet 14 played a role in one of the last actions of the war. During November 1918, one aircraft was used to transport a German military officer, Major von Geyer, from Tergnier and Spa. It was covered in large white flags of truce to avoid being attacked.[15]
The type continued to be widely used after the war, equipping the French occupation forces in Germany and being deployed to support French troops in the colonies.[13] A special version was developed for the harsh conditions encountered overseas, designated "14 TOE" (Théatres des Operations Extérieures). These saw service in putting down uprisings in Syria and Morocco, in Vietnam and in the French intervention in the Russian Civil War. The last trainer examples were not withdrawn from French military service until 1932.
Other air arms using the type included Brazil (30), China (70), Czechoslovakia (10), Denmark (4), Finland (38), Greece (approximately 42), Japan (2), the Siamese Air Force (42), Uruguay (9) and Spain (approximately 180). The Polish Air Force used 158 Breguet 14s, about 70 of them being used in combat in the Polish-Soviet war. In Japan, Breguet 14s were licence-built by Nakajima. The type was also heavily used in various internal wars in China during the 1920s and 1930s.[13]
Weeks after the signing of the Armistice, the Breguet 14 was used to conduct several long-distance flights to demonstrate its capabilities. On 26 January 1919, a double-crossing of the Mediterranean was flown using the type by Lt Roget and Captaine Coli. On 5 April, Roget flew from Lyon to Rome and then to Nice. Roget and Coli later establish a new French long-distance record flying the Breguet 14, flying from Paris to Kenitra, Morocco, a distance of in 11 hours 15 minutes. Aviation pioneer Pierre-Georges Latécoère converted one example to conduct experimental in-flight refuelling operations.[16] After the war, Breguet manufactured of dedicated civil versions of the Breguet 14. The 14 T.2 Salon carried two passengers in a specially modified fuselage. An improved version, the 14 Tbis, was built as both a land-plane and seaplane.[17] The 14 Tbis also formed the basis of the improved 14 Tbis Sanitaire air ambulance version, and 100 mail planes custom-built for Latécoère's airline, Lignes Aeriennes Latécoère.[18] After changing its name to "CGEA", the airline used, among others, 106 Breguet 14s for flights over the Sahara Desert. The 18 T was a single 14 T re-engined with a Renault 12Ja engine and equipped to carry four passengers.[18] When production finally ceased in 1928, the total for all versions built had exceeded 7,800 (according to other sources, 8,000 or even 8,370).
Data from:[19]
Spain
El Salvador
Greece
United States