Fire from the Sky: The Terror of the Paris Gun
On the 23rd March 1918 at 7.18 in the morning the city of Paris was rocked by a sudden, unexpected explosion on the Quai de la Seine. The blast came without warning, and many thought the initial explosion to be some kind of accident, a gas leak or something of that kind.
However as the day wore on the populace became more and more afraid as the blasts continued at roughly 15-minute intervals. 21 separate explosions were reported that first day, scattered across the city.
France, along with the rest of Europe, was still trapped in the grim deadlock of World War One and the nation was on high alert. But the trench lines and the fighting were still some 100km away, and the explosions seemed to suggest sabotage, or some other hidden attack.
Authorities and the general public alike were at a loss to explain the cause, the manner or even the possible targets for these explosions. They were all over the city and while some were responsible for damaging infrastructure, others seemed to target irrelevancies like public gardens.
That first day the explosions killed 15 people and injured a further 36. Panic swept through the city and the train stations became choked with thousands of people trying to leave. By the end of the day the sale of rail tickets had been suspended due to overwhelming demand.
From where had the blasts come? The initial assumption was that a German zeppelin had silently passed over the city undetected, perhaps too high to be seen, and dropped bombs onto the populace below.
This would account for the randomness of the explosions, and in fact this was the real cause for such arbitrary targeting. But this was no zeppelin or any kind of aircraft. The shots had instead been fired by the Kaiser Wilhelm Gun, which quickly earned the nickname the “Paris Gun.”
And they were fired from 120 km away.
A Monster
In fact, there were several Paris Guns deployed in the last year of the Great War. These enormous gun emplacements had a range greater than any other cannon known at the time, and fired from so far away that the sound of the shot could not be heard: the shells arrived silently and without any warning.
The guns employed “Langer Max” barrels originally intended for naval use, seven in all. At 21 m in length these were the largest barrels ever used in World War One, and were even large enough to meet the modern definition of “large-caliber artillery”.
The barrels were either delivered to a specialized emplacement by rail or attached to a vast tracked base which allowed them to be redeployed. Each gun took 80 Imperial German sailors to operate.
Shells fired from the gun travelled for more than 3 minutes, flying at speeds of almost five times the speed of sound and reaching an altitude of more than 42 km. In 1918 nothing flew higher or faster than these projectiles.
Such a high arc was necessary to boost the gun’s range by having it fly through the thinner air of the stratosphere, but created many additional problems for the crew. The gun had to be aimed taking into account the Coriolis Effect caused by the rotation of the Earth, and struggled to hit any target smaller than a city.
Secrecy was also considered of paramount importance. Every time a Paris Gun was fired there was an accompanying chorus of shots from lesser artillery surrounding it, in an effort to mask the enormous sound of the shell being launched.
The shells themselves however were not that dangerous by WW1 artillery standards. The enormous range meant it was robbed of much of its destructive potential, with only 7kg of TNT in the 106 kg shell, less than 7% of its total weight.
There were more problems, too. Each time the gun was fired it caused significant damage to the inside of the barrels, scraping away a large amount of steel. Shells for the Paris Gun were matched to each barrel in a set and numbered, each shell being slightly larger than the last.
Use a shell with too low a number and the space around the shell in the barrel would cause wild inaccuracies; use a shell with too high a number and the gun could explode. Each shell also had to be fired with a varying amount of propellant, depending on measurements taken of the barrel after each shot, and after 65 shells had been fired the barrel was useless and needed to be rebuilt.
So this biggest of World War One guns was highly inaccurate, difficult to move and set up, required a vast and highly trained crew, had a small destructive payload and almost destroyed the gun with each firing. This was clearly an ineffective weapon in conventional terms, but the Germans had intended it to have a different effect.
The Paris Gun was meant to be a psychological weapon, bringing arbitrary and sudden destruction to the inhabitants of a city who thought themselves far from danger. And, while the source of these Paris explosions remained a mystery, it was indeed highly effective.
The French authorities diverted enormous resources to finding the source of these blasts and stopping them. It was initially speculated that this was indeed the work of a gun, but one smuggled to a position close to the city: quarries around Paris were searched in the hopes of finding the hiding place.
But the authorities quickly realized that this was a new long-range gun, and reconnaissance flights over German lines found three emplacements within a few days of the first attack, in part by analyzing the explosions and working out a likely trajectory for the shells.
Over the spring and summer of 1918 as many as 367 shells were fired at Paris, killing 250 and wounding 620, including 91 members of the congregation of a church killed when its roof collapsed. In the end it was only stopped as the Allies pushed the German lines back and Paris became safely out of range.
No Paris Gun was ever captured by the advancing Allies. All were destroyed before the end of the war, leaving their exact specifications uncertain as each was different. Were it not for a research paper written in the 1920s we would know almost nothing about them at all.
The Germans tried this technology in WW2, but for more tactical uses. Never again would such a weapon be used in this way, and never again would the inhabitants of Paris find themselves under divrect attack from an enemy that was invisible, silent, and murderous.
Top Image: The enormous, and enormously inaccurate, Paris Gun. Source: Unknown Author / Public Domain.
