Canon de 194 GPF – The French SPG Powered by Electricity
Towards the end of the First World War French engineers produced this, the Canon de 194 GPF, an advanced self-propelled gun (…kinda) that carried guns ranging in calibre from 194 mm to 280 mm! This electric vehicle was one of the earliest of its type, and helped pave the way for a class of vehicle that is even more relevant today than it was a century ago.
While its creators didn’t invent the concept of the self-propelled gun (SPG), the Canon de 194 GPF incorporated took a very unusual approach to solving the problems facing engineers who were exploring an entirely new type of machine. As it was difficult to fit a massive gun and all of its ammunition onto one chassis, they simply divided the vehicle into two!
One carried the gun, and the other carried the ammunition, related supplies and even powered the gun carrier via an electric cable.
This is a deeper dive into this peculiar French SPG.
On the Western Front in the First World War the tactical situation varied as the war progressed, with the early manoeuvre combat of 1914 bogging down into trench warfare in 1915. This static stalemate lasted until early 1918, when the Allied forces again broke free of the trenches and started to aggressively manoeuvre on open ground in rapid tactical advances. With Allied infantry and tank formations advancing freely into German front line positions, it was realised that artillery units needed to increase their mobility to keep up with other fighting units when the front shifted.
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The trench warfare deadlock, and the subsequent fighting over relatively shallow areas of the front lines did much to worsen the general conditions at the Forward Edge of the Battle Area (FEBA), with constant artillery barrages denuding the countryside of trees and any greenery. Combined with the constant soaking rain over three years, these artillery contests ensured that the land was torn up, churned into a quagmire which greatly inhibited any tactical movement by infantry units.
Field artillery formations in particular found their mobility sharply reduced by the appalling ground conditions encountered near the front.
As nearly all artillery was horse-drawn, the treacherous ground and muddy conditions greatly hindered mobility. An attempt to improve mobility in artillery systems using wheeled vehicles was trialled, but the results were disappointing. It was realised that only a tracked vehicle could deal with muddy and boggy conditions, and all research on SPG systems concentrated on the adaptation of tracked chassis into mobile guns systems.
Both the Central Powers and the Allies experimented with mobile artillery systems, with most of this innovative design work commencing after the front cracked open in 1917-18. The British Army fielded a mobile artillery gun in 1917, and the French Army followed in late 1918 with the Canon de 194mm GPF self-propelled artillery system.
Development of this type of vehicle was well under way in 1917, with a self-propelled gun based on the St Charmond tank and carrying a 120 mm gun being tested that year. However, the gun was deemed too small for such a large machine, and so work carried on, which eventually resulted in the Canon de 194 GPF.
Without any “rule book” to follow, the Canon de 194 GPF was very different to self-propelled guns of today. It was comprised of two separate vehicles; one that carried the gun (gun carrier), and one that carried the ammunition (lead vehicle). Both were driven by electric motors.
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For the GPF chassis the French used a modified Saint-Chamond tank (with a track system licenced from Caterpillar in the United States) for both the gun carriage and the mobility tractor.
Some do not regard the Canon de 194 GPF as a true self-propelled gun, as the gun carrier did not contain its own power source. That’s because instead, power for its electric motors was generated by an engine in the ammunition carrier, transferred via a cable.
The gun carrier mounted the main cannon, which was aligned fore-and-aft for any tactical movement. While this set-up appeared more complicated than the single-vehicle British equivalent, it was actually more advanced in design, being able to be driven by only one person and was also fitted with new-design hydraulic brakes.
Production commenced in April 1918, and the first example was showcased two days before the Armistice, however no cannon was fitted to this vehicle. The proposed 155 mm gun was replaced by a 194 mm cannon from the APX arsenal, and by June 1919 the remaining technical hurdles had been overcome, and the vehicle entered serial production. A total of 50 examples were manufactured before production ceased in 1920.
Canon de 194 GPF Design
As might be expected in a large chassis used to transport a heavy cannon, the dimensions of the Canon de 194 GPF gun carrier were impressive; a height of 7.7 metres (25 feet), a width of 2.5 metres (8 feet) and an overall length of 7.3 metres (24 feet). The weight of the vehicle came in at 29,600 kg (65,300 lbs).
As mentioned, the ammunition carrier generated power for both vehicles with its engine, a Panhard SUK4-M2 engine, which produced 120 brake horse power. This engine powered a generator, which in turn supplied electrical power to four drive motors, two in each carriage, or one-per track. A 50 meter-long electrical cable was used to transfer power to the gun carriage.
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This drivetrain combination produced modest performance figures; a top speed of 10 km/h (6 mph) on road surfaces, and a miserable 2.5 km/h (1.5 mph) in cross-country conditions.
The Canon de 194 GPF was equipped with a 194 mm cannon, which was supplied by the APX arsenal at the suburb of Puteaux in Paris. This was a weapon of 42.2 calibres, a length of 6.5 metres (21 feet) and had a rate of fire of one round per minute. The cannon had a maximum range of around 20,000 metres and a muzzle velocity of 660 m/s (2,100 f/s), but an improvement in 1921 saw the muzzle velocity increase to 725 m/s (2.380 f/s).
While both vehicles technically used the same chassis, the lack of engine in the gun carrier freed up room for the gun, allowing it to be set lower and better accommodate its recoil. In addition, as each track was powered independently by electric motors, they had the ability to neutral turn. This also served as the gun’s means of horizontal traverse, eliminating the need for a bulky traverse mechanism.
As per normal with early self-propelled guns like the GPF there was no provision for shelter from enemy fire for the gun crew, nor were any auxiliary weapons fitted for self-defence from infantry attack.
The same chassis used for the Canon de 194 GPF was also fitted with a few other much larger weapons. One of these was a 220 mm St Chamond howitzer, which fired a 100 kg (220 lb) projectile. This version did not enter service, however. Even larger was a 280 mm TR Schneider howitzer, which fired a huge 200-270 kg (440 – 595 lb) projectile. Known as the Mortier 280mm TR de Schneider sur affût-chenilles St Chamond, 25 were built.
The Canon de 194 GPF arrived just too late to see service in the First World War, but the good qualities of its design saw manufacturing continue until 1920, with a total production run of 50 units. The French Army was the only operator of the platform in the inter-war years, with most examples equipping artillery units based in the Valence region, serving alongside other self-propelled gun systems introduced into service at this time.
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Thirty-six examples of the GPF were still in service at the commencement of the Battle of France at the start of the Second World War, and these were rushed to help support artillery units in the vicinity of the Maginot Line. Finding themselves in a poor tactical location as the German Army bypassed the fixed defences of the Maginot Line, most of the GPFs were quickly captured and re-purposed by both the Germans and the Italians.
Most of the surviving examples captured by the Axis forces had the cannons removed, and these guns were incorporated into the Atlantic Wall, and also equipped fixed fortifications in Denmark after that country was occupied. The Italians used two 194mm guns stripped from GPFs to equip coastal batteries near Rome.
The German Army did retain some complete Canon de 194 GPF self-propelled guns under the designation of 19.4 cm Kanone 485(f), and history records that three examples saw active service with the Wehrmacht on the Eastern Front from 1942 onwards. Battle damage, attrition, and the stripping of most cannons from their chassis from 1940 means there were few surviving vehicles after the end of the fighting in the Second World War, and today only a single example exists, in the U.S. Army Artillery Museum in Fort Sill, Oklahoma.
A single 280 mm Schneider howitzer-armed example was found in Germany, and is now on display in Dresden.
The design concept of the self-propelled gun proved itself with distinction during the Second World War, and mobile artillery systems have been standard equipment around the world since 1945. While armies around the world today employ both towed and self-propelled artillery gun systems, it is widely recognised that SPGs are for more survivable under modern ground combat conditions, due to their ability to quickly re-locate after firing a barrage at the enemy.
Most weapons systems have a design forebear which had proved the basic utility of the concept, and the self-propelled gun is no exception. The German Army did much of the hard work in SPG design and employment during the inter-war period and from the start of the Second World War, but other nations also helped prove the concept of the SPG and produced early examples which saw active service.
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The French Army contributed to this military innovation with the introduction of the Canon de 194mm GPF, one of the world’s first operational mobile artillery systems. Crude and slow as it may be, it is still an important ancestor of the modern self-propelled gun, and did much to introduce the widespread employment of mobile artillery gun systems, and prove the basic concept under combat conditions.