Steam cannon
A cannon that launches projectiles using heat and water.
A steam cannon uses heat and water, or high-pressure steam from a boiler, to fire a projectile. The first such weapon is sometimes attributed to Archimedes during the Siege of Syracuse, and Leonardo da Vinci also designed one, which he called the Architonnerre. Da Vinci’s early concept involved a large metal tube—preferably copper for its heat conductivity—placed in a furnace. One end was capped, and a projectile was loaded into the other. After the tube was heated sufficiently, a small amount of water was injected behind the projectile. Da Vinci theorized that the water would instantly turn to steam, forcing the projectile out of the barrel.
During the steam age, several attempts to build working steam machine guns and cannons, based on steam locomotive technology, all failed. In 1826–29, Colonel Karelin of the Imperial Russian Corps of Communications developed an experimental 17.5 mm bore steam cannon. Its barrel was green copper inside a red copper casing, and it was said to fire cannonballs at 50 rounds per minute. Tests in 1829 failed, and the gun was sent to the St. Petersburg arsenal; it now resides in the Military Historical Museum of Artillery, Engineers and Signal Corps there. The Winans Steam Gun (1858–1861) was a steam-powered centrifugal weapon used by the Confederates in the American Civil War, but it saw no successful combat.
A successful World War II steam cannon was the Holman Projector, which launched explosive Mills bombs into the air to create a defensive barrage against low-flying enemy aircraft. These later models fired by quickly releasing a burst of high-pressure steam into the chamber behind the projectile, accelerating it down the barrel much like a powerful air gun. The principle was essentially that of a steam engine, with the projectile replacing the piston. Holman Brothers of Cornwall, who made pneumatic mining equipment, originally powered the Projector with compressed air from high-pressure cylinders. After the SS Highlander successfully defended itself in August 1940 by downing two Heinkel floatplanes, demand for the projectors grew for small naval trawlers. Since these trawlers ran on steam but lacked compressed air systems, the Admiralty asked Holmans to create a steam-powered version. Treve Holman worried about heat affecting the Mills bomb projectile, so a test was arranged: a borrowed council steam roller heated the Pr
- first_claimed_designer
- Archimedes (during the Siege of Syracuse)
- noted_designer
- Leonardo da Vinci
- field
- Weapons technology
- known_for
- Launching projectiles using steam pressure
- notable_example
- Holman Projector (World War II)
Lore & Background
The early device would consist of a large metal tube, preferably copper due to its high thermal conductivity, which would be placed in a furnace. One end of the tube would be capped and the other loaded with a projectile. Once the tube reached a high enough temperature, a small amount of water would be injected in behind the projectile. In theory, da Vinci believed the water would rapidly expand into vapour, blasting the projectile out of the front of the barrel.
In 1826–29, a 17.5 mm bore experimental steam cannon was developed by Colonel Karelin of the Imperial Russian Corps of Communications. The barrel was of green copper in a red copper casing; it was capable of firing cannonballs at a rate of 50 rounds per minute. Tests in 1829 failed and the gun was transferred to the arsenal of St. Petersburg. It is now in the Military Historical Museum of Artillery, Engineers and Signal Corps in St. Petersburg.
The Winans Steam Gun of 1858–1861 was a steam-powered centrifugal gun used during the American Civil War by the Confederates. It used steam power and centrifugal forces to propel projectiles. It was not used successfully in battle.
Reader's Guide
A successful World War II steam cannon was the Holman Projector, which was used to launch explosive Mills bombs into the air to create a defensive barrage against low-flying enemy aircraft. These later steam cannons were fired by rapidly introducing a burst of highly pressurized steam into the chamber behind the projectile, accelerating the projectile up the barrel to a high speed, much like an air gun, only more powerful. The fundamental function of the device was basically the same as a steam engine, only with a projectile taking place of a piston. The Holman Projector was produced by Holman Brothers of Cornwall, who specialised in pneumatic equipment for mining. The first Projectors were powered by compressed air, stored in high pressure cylinders. After a successful defence of the SS Highlander in August 1940, downing two Heinkel floatplanes, there was a demand for more projectors to be fitted to small naval trawlers. Since these vessels were steam-powered but had no compressed air system, the Admiralty requested Holmans to develop a steam-powered version of the Projector. There were concerns by Treve Holman over the effects of heat on the Mills bomb projectile. A test was arranged, where a borrowed council steam roller was used to 'cook' the Projector and projectile, at 190 °C for 20 minutes before the projectile was safely fired to 1,000 feet altitude.
Did You Know?
- It has been claimed that the first steam cannon was designed by Archimedes during the Siege of Syracuse.
- Leonardo da Vinci designed a steam cannon called the Architonnerre.
- A 17.5 mm bore experimental steam cannon developed by Colonel Karelin in 1826–29 failed tests in 1829 and is now in a museum in St. Petersburg.
- The Holman Projector, a successful World War II steam cannon, was tested by cooking the projectile at 190 °C for 20 minutes before firing it to 1,000 feet altitude.
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