Voisin L

{{Infobox aircraft begin

| name = Voisin L

| image = Voisin_L_Gnome_Engine.jpg

}}{{Infobox aircraft type

| type = Reconnaissance, Bomber, Trainer

| manufacturer = Voisin
Anatra
Dux

| designer = Gabriel Voisin

| first flight = 1912

| introduced =

| retired =

| status =

| primary user = Aéronautique Militaire

| more users = Aéronavale
Imperial Russian Air Service

| produced =

| number built = 70 (France)
400 (Russian Empire)

| developed from = Voisin Type Bordeaux

| developed into = Voisin III

| variants with their own articles =

}}

The Voisin L was a pusher biplane developed for the French Army's 1912 trials where it performed successfully. About 70 were built in France with around 400 manufactured under license in the Russian Empire. The aircraft was the first in a series of military pusher biplanes from Voisin all of which had similar design characteristics. During the early stages of World War I the aircraft were primarily used for reconnaissance.

The factory name for the aircraft was the Voisin L. From 1915, the official French military designation for Voisin L aircraft powered by the Rhône 9C was the Voisin I{{efn|The 1913 edition of Jane's All the World's Aircraft refers to the Voisin 1907 biplane as the Voisin No. I{{Cite book |last=Jane |first=Fred T |title=All the World's Aircraft |date=1913 |publisher=Sampson Low Marston |location=United Kingdom |pages=4d |chapter=Aerial "Who's Who" |lccn=69-14964}}}} while those fitted with the Gnome Monosoupape 7A were designated as the Voisin II.

Design

The Voisin L had equal-span wings with no dihedral. A cruciform tail was attached to the wings with booms. A streamlined nacelle carried a pilot and observer in front with a single rotary engine at the rear.{{Cite book |last=Simons |first=Graham M |title=Early French Aviation (1905-1930) |date=2019 |publisher=Pen and Sword |isbn=9781526758750 |chapter=Hydro avions}} Steel tubing was used throughout the structure, making the Voisin-L a robust aircraft for its time-period.{{Cite book |last=Ulanoff |first=Stanley M |url=https://archive.org/details/illustratedhisto0000ulan/page/134/mode/2up |title=Illustrated history of World War I in the air |date=1970 |publisher=Arco Publishing |isbn=9780668017688 |location=United States |pages=135 |chapter=Bomber and Reconnaissance Aircraft}}

File:Voisin_L_floatplane_Feb_1915.jpg

Land-based versions of the aircraft featured a distinctive quadricycle landing gear. A floatplane version was produced with the quadricycle landing gear replaced with three flat bottomed pontoons.

Voisin-Ls can be distinguished from later Voisin pushers as they were fitted with air-cooled rotary engines and so lacked the bulky radiators seen on Voisin's later aircraft which were powered by water-cooled Salmson 9, Peugeot 8Aa and Renault 12Fe aero-engines.{{Cite book |last=Pinto |first=Renato |title=Perfiles Historia De La Aviacion |date=1981 |publisher=Viscontea |volume=1 |location=Spain |pages=65-72 |language=Spanish |trans-title=History of aviation |chapter=Voisin L}} The rotary engine on the Voisin L drove a large two bladed wooden propeller via a reduction gearbox.{{Cite journal |last=Pernet |first=Andre |date=January 1963 |title=La Premier Victorie Aerienne |trans-title=The first air victory |url=https://gallica.bnf.fr/ark:/12148/bpt6k5322978z/f40.image |journal=Aviation |language=French |issue=362 |pages=46-47}}

==Operational history==

The prototype Voisin L was developed for the 1912 French military trials using the same sturdy biplane design as the Voisin military pushers exhibited in 1910 and 1911, which were themselves developments of the Voisin Type Bordeaux.{{Cite book |last=Opdycke |first=Leonard E |title=French Aeroplanes before the Great War |date=1999 |publisher=Schiffer Military History |isbn=0764307525 |location=United States |pages=269-271}} By 1912 Gabriel Voisin’s focus was on military sales as the companies' designs had fallen out of favor with the sports aircraft market which had moved towards to light weight tractor monoplanes.{{Cite journal |last=Pernet |first=Andre |date=November 1962 |title=Des ateliers à l’usine |trans-title=Series factory production |url=https://gallica.bnf.fr/ark:/12148/bpt6k5322889d/f43.image|journal=Aviation |language=French |issue=359 |pages=56-57}}

Following the aircraft's successful performance in the 1912 military trials, the French army placed an order for twelve Voisin L aircraft. The order from the military transformed the fortunes of Gabriel Voisin's business and led to an immediate expansion of the company's factory at Issy-les-Moulineaux. The first Voisin L aircraft was delivered to the French army in May 1913. The French Navy placed orders for the floatplane version of the aircraft in August 1913 with the first delivery taking place in October 1913. A total of 70 Voisin L aircraft were built in France{{Cite journal |last=Pernet |first=Andre |date=May 1963 |title=Caracteristiques des Voisin 1914-1918 |trans-title=Voisin aircraft specifications 1914-1918 |url=https://gallica.bnf.fr/ark:/12148/bpt6k53228650/f43.image |journal=Aviation |language=French |issue=371 |page=55}} with the entire production run having been completed before the start of World War I.{{Cite journal |last=Pernet |first=Andre |date=February 1963 |title=Bombardiers en action |trans-title=Bombers in action |url=https://gallica.bnf.fr/ark:/12148/bpt6k5324238n/f36.item|journal=Aviation |language=French |issue=364 |pages=48-49}}

At the start of World War I, Voisin L aircraft (types 1 and 2) were in service with four French squadrons. The aircraft were used for artillery observation and as daylight bombers. Voisin-Ls were in front line service till October 1914 after which remaining aircraft were transferred to training schools. In the winter of 1914/15 the French Airforce was reorganized with production focused on a smaller number of dedicated types. One of the types selected for mass production was the Voisin III.{{Cite book |last=Sumner |first=Ian |title=The Kings of the Air: French Aces and Airmen of the Great War |date=2015 |publisher=Pen and Sword |isbn=9781783463381 |pages=41}}

In the Russian Empire, Voisin L aircraft were manufactured by Anatra in Odesa{{Cite book |last=Robinson |first=Antony |title=The Illustrated Encyclopedia of Aviation |date=1979 |publisher=Marschal Cavendish |isbn=085685574X |volume=1 |location=United Kingdom |pages=57 |chapter=Wings for the Tzar}} and the Duk Factory in Moscow. Both manufacturers also license built Voisin III aircraft.{{Cite book |last=Blume |first=August G |title=The Russian Military Air Fleet in World War I |date=2010 |publisher=Schiffer |isbn=978-0764333514 |volume=1 - A chronology 1910-1917 |location=United States |pages=297-298}} A total of 400 Voisin L aircraft were built in the Russian empire with the type remaining in front line service with the Imperial Russian Air Service into 1916.{{Cite book |last=Kulikov |first=Victor |title=Russian Aces of World War 1 |date=2013 |publisher=Osprey Publishing Limited |isbn=9781780960609 |location=United Kingdom |chapter=Aces of the 9th AOI}}

The Voisin L was the first in a series of pusher biplanes referred to as the 13.5 meter{{efn|Although collectively known as the Voisin 13.5 meter, later aircraft in the series have larger wingspans.}} or "L" series with STAe designations running from Voisin I to XI. Around 6,000 of the Voisin 13.5 meter series aircraft were built between 1913 and 1918.

Variants

File:Voisin L - Geared Gnome Monosoupape rotary engine.png

Type 1, Voisin I or Voisin-Rhône - Fitted with the Rhône 9C{{Cite book |last=Pinto |first=Renato |title=Perfiles Historia De La Aviacion |date=1981 |publisher=Viscontea |volume=1 |location=Spain |pages=65-72 |language=Spanish |trans-title=History of aviation |chapter=Voisin L}}
Type 2, Voisin II or Voisin-Gnome - Fitted with a Gnome rotary engine. Early examples were fitted with the Gnome Omega. Later examples used the seven-cylinder variant of the Gnome Monosoupape.
3 B.2 - Fitted with dual controls for flying school use. Powered by the Rhône 9C.
3 D.2 - Fitted with dual controls for flying school use. Powered by the Gnome Monosoupape 7A.

Type 1 and 2 are designations applied retrospectively by the French military from 1915 onwards. Contemporary names for the aircraft included the Voisin model 1912 and Voisin 13.5 meter. In all cases Voisin L was the aircraft's factory designation.

Operators

;{{flag|French Third Republic|name=France}}

;{{RUS}}

Imperial Russian Air Service

Specifications (Type 1)

{{Aircraft specs

|ref=Renato

|prime units?=met

|crew=2 (pilot and observer)

|length m=10.5

|length note=

|span m=13.5

|span note=

|height m=2.9

|height note=

|wing area sqm=42

|wing area note=

|airfoil=

|empty weight kg=825

|empty weight note=

|gross weight kg=1100

|gross weight note=

|max takeoff weight kg=

|max takeoff weight note=

|fuel capacity=

|more general=

|eng1 number=1

|eng1 name=Le Rhône 9C

|eng1 type=rotary engine

|eng1 kw=60

|eng1 note=

|prop blade number=2

|prop name=fixed-pitch pusher propeller driven at ~600 rpm (half the engine speed) via a gearbox

|prop dia m=

|prop dia note=

|max speed kmh=95

|max speed note=

|cruise speed kmh=

|cruise speed note=

|stall speed kmh=

|stall speed note=

|never exceed speed kmh=

|never exceed speed note=

|range km=

|range note=

|combat range km=

|combat range note=

|endurance=

|ceiling m=

|ceiling note=

|climb rate ms=

|climb rate note=

|time to altitude={{cvt|1000|m|ft|0|abbr=on}} in 11 minutes{{cite magazine |author= |date=22 January 1914|title=Naval and Military Aeronautics|magazine=The Aeroplane|location=United Kingdom|pages=86}}

|wing loading kg/m2=

|wing loading note=

|bombs=Up to {{convert|130|lb|kg|0|abbr=on|order=flip}} carried inside the nacelle and dropped over the side by the observer{{Cite book |last=Taylor |first=John W. R. |title=Combat aircraft of the world: from 1909 to the present |date=1969 |publisher=Putnam |location=United Kingdom |page=131 |lccn=68-25459}}}}