Paris gun
Under the name Paris Gun was in the First World War, a German long-range gun of the company Krupp of caliber 21 cm known. It had an exceptional range of about 130 kilometers. Between March 23, 1918 and August 8, 1918, three or two Paris guns fired around 800 shells at Paris.
Structure and data
The howitzer (able to shoot up to an angle of 55º) had a barrel length of 37 meters, i.e. H. of 176 calibers (L / 176). The pipe was a construction of a 17 m long (jacket) pipe with an inner diameter of 38 centimeters (from the naval gun 38 cm SK L / 45 ), into which a 30 m long drawn 21 cm pipe ( core pipe ) was inserted. Finally, a 6 m long smooth pipe (the so-called "bag") was added. The extra-long construction was protected against sagging by a characteristic suspension bridge-like tensioning mechanism. This gun barrel was known as the "Kaiser Wilhelm barrel". It fired high explosive shells weighing 106 kilograms (explosive charge about 7 kg) with a ballistic hood and a muzzle velocity of up to 1645 meters per second. The howitzer had a total mass of around 140 tons and was transported to the site by rail. Because of that, however, it was not a railway gun, but shot from rotating so-called shooting frames from stationary beds made of concrete or steel. The three different gun emplacements were located somewhat off the existing railway lines, each in the cover of a large forest. A multi-track connection was built in the position. Away from the actual position, shear positions were laid, even with a siding.
The range of around 130 km was based on a ballistic feature. With a high departure angle of up to 55 °, a very strong propellant charge and the extra-long tube, the summit height could be placed in the upper part of the stratosphere at around 38 to 40 km. As a result, the bullet flew for a long time through very thin layers of air, so that the trajectory largely resembled that of a shot in a vacuum. All other long-range guns used in World War I achieved a range of "only" about 40 km.
The development of the Paris guns began in 1916. The artillery designer ( major ) Fritz Rausenberger from the Krupp company, who had already designed the " Big Bertha ", played a key role in this. The development took place on the firing range of the Krupp company near Meppen , which is now the Defense Technology Office 91 . Since the test area in Emsland was too small and a grenade hit the Wester-Moor near Saterland outside the test area due to a miscalculation, one had to switch to the Altenwalde firing range , since one could shoot all the way to the open North Sea . On November 20, 1917, the first completed Paris gun was successfully tested in Altenwalde near Cuxhaven on the North Sea with a westerly firing direction along the East Frisian Islands. By the beginning of 1918, two more Paris guns were built, which were used together as part of the German spring offensive on March 23, 1918 for the first time from the 1st position, the forest of Saint-Gobain near Crépy-en-Laonnois .
The projectiles reached an altitude of about 40 km and a flight time of three minutes. The multi-part propellant charge, consisting of a brass cartridge with a propellant charge and two part charges in silk propellant bags, weighed up to 196 kg. In order to achieve a uniform performance, the highly explosive propellant charges made of tubular powder C / 12 were stored at a constant temperature of 15 ° C near the gun position. During the approximately 20 minutes on average between the shots, the enlarged cargo space had to be measured, the gas pressure measurements evaluated and numerous calculations carried out. In addition to the usual influences in artillery shooting, other significant, previously unknown factors had to be taken into account. The firing range of about 130 km, measured on the circumference of the globe , was shortened by about 800 meters when viewed as a chord . Due to the excessively long projectile flight time, even the rotation of the globe during this time had to be calculated for the shot values, so that the bombardment was actually a shooting with lead at a moving target.
Proper fire control was not possible due to the distance; other options had to be found for this. The situation of the impacts is said to have been observed and reported by German spies in Paris, among others. In the beginning there were also reports in the city's newspapers that were delivered to other European countries and evaluated there by German authorities until the French censors were able to prevent this. Alternatively, the position of the impacts in the longitudinal direction of the shooting was estimated by measuring the gas pressure during the shot using so-called "Krupp measuring eggs" (copper compression bodies) inserted into the cargo space.
Due to the enormous energy of the propellant charge at a temperature of 2,000 ° C and a gas pressure of up to 4,800 bar, the gun barrel was emptied when firing. With each shot, the caliber increased slightly, which had to be compensated for by means of numbered grenades with a correspondingly increasing diameter and a constant increase in the propellant charge. Most of the brass cartridge burned when it was fired. Even the first copper guide bands to absorb the twist did not withstand the temperature and pressure. Therefore, additional twist grooves had to be cut into the steel shell of the grenades, with the result that the gun barrels were also worn out prematurely. The grenades were literally "screwed" into the grooves and fields of the pipe when loading. The useful life of a barrel from the 1st position was only about 65 rounds.
After this first performance, the pipes then had to be bored open at Krupp in Essen to a caliber of 22.4 and then a further 23.8 cm. The tube volume expanded as a result of the boring, and the gas pressure fell when it was fired. These pipes could only be used from the 2nd (Beaumont-en-Bein) and 3rd (Bruyères-sur-Fère) positions, which are closer to Paris. There were seven pipes in total.
Not only the position but also the shooting itself had to be camouflaged. In order to make the French sound measurement location more difficult, about 30 other heavy German batteries fired from neighboring positions at the same time as one of the Paris guns. The shooting was mostly only during the day, since the huge muzzle flash alone would have given away the position at night. The shelling was also stopped during French aviation danger. The Paris battery was secured by an infantry battalion and ten aviation detachments.
Use and whereabouts
Even if the specialist literature sometimes writes about the Paris gun, a total of three such howitzers were used. The Paris guns had no military use due to their use against the civilian population. The hit in Paris initially achieved the desired psychological effect with confusion and fear, but it fizzled out after a short time due to the low explosive charge of the grenade and the recognizable lack of precision of the fire control. A total of 256 civilians were killed and 620 wounded, of which there were 88 dead and 68 wounded in a hit on the parish church of Saint-Gervais-Saint-Protais during the Good Friday service on the afternoon of March 29, 1918. However, German propaganda used these alleged successes to bolster morale on the home front .
Although it was an artillery use on land, the operation was in the hands of the Navy , as they had more experience with larger guns. A gun crew consisted of 60 to 80 marines, plus a group of civil engineers for technology and surveying. Vice-Admiral Maximilian Rogge was in charge of the shooting . On the German side, the expectations were so great that even Kaiser Wilhelm II visited the position on the first day of the mission and watched the shooting.
Already in the 1st position one of the three guns exploded on March 25 when it was shot down, killing seventeen soldiers of the operating team. The remaining Paris guns fired a total of about 400 projectiles from three different positions until August 8, 1918, most recently again at Beaumont-en-Bein. The average rate of fire was 8 rounds per day. Around 180 shells hit Paris scattered within the old town, the rest on the outskirts. Due to the constantly deteriorating military situation and the German withdrawal, the goal was soon no longer attainable. The two remaining guns and their replacement barrels were withdrawn from the front and scrapped. The construction plans were also hidden or destroyed by the Germans. After the surrender, despite a search at Krupp, the Allies could no longer understand how such a howitzer could have been built. The concrete bedding of the first gun in the position near Crépy-en-Laonnois remained a relic . Another relic can be found at the site of the last position in the Chatel forest, north of Château-Thierry . A metal bed was used here. It left a circular hole in the forest that has been preserved to this day. There are also remains of earthworks in the form of walls for the rail feed east of the hole in the forest in the direction of the existing railway line.
The long range was later not significantly exceeded by any conventional gun. After the First World War, France built a similar howitzer, the model 23 remote railway gun, with a caliber of 21 cm, a range of 120 km, a projectile weight of 108 kg and a v 0 1450 m / s. In the course of rearmament, the German Wehrmacht then commissioned the K 12 . By this time at the latest, such long-range guns were out of date, as their purpose was now much easier to achieve through air attacks. The peak height of the Paris Gun was only exceeded by the V2 . A late continuation of this oversized artillery was found in the 1960s in the HARP project by Canadian Gerald Bull .
literature
- Henry W. Miller: The Paris Guns - The bombardment of Paris by German long-range guns and the offensives of 1918. Wilhelm Limpert, Berlin and Dresden 1936.
- Gerhard Taube: German railway guns. Tube artillery on rails. Motorbuch-Verlag Stuttgart 2001, ISBN 3-613-01352-5 .
- Blackboard on the model in the Defense Technical Study Collection in Koblenz .
Web links
- FirstWorldWar.com: The Paris Gun (English)