Mortars have been used by armies almost since gunpowder was invented. While cannons were direct-fire weapons – meaning that their barrels were more of less level with the ground when fired – mortars, almost without exception, only fire on a near-vertical angle. “Howitzers” are a compromise, firing heavier shells than mortars, but can more easily employ direct-fire.
Due to the technological limitations of shell and fuse design in past centuries, mortars were quickly eclipsed in most armies, being relegated to siege warfare and being used on specially designed warships. During the American Civil War, massive mortars were employed in both sieges, and were mounted on railroad cars. But still, the rudimentary fuse technology severely restricted the weapon’s use.
By the early 1900’s, however, technology had caught up. When World War 1 settled into its “trench warfare” phase on the Western Front, all sides began looking for anything that could break the deadlock. Among the solutions were massive barrages of cannon and howitzer fires, poison gas, sub-machine guns (SMG’s), heavier machine guns, the earliest tanks, and airplanes, it would be easy to view the mortar as an “also-ran”.
That would prove, very definitely, to not be the case.
In 1915, as the slaughter in the trenches ground on, Sir Wilfred Stokes, KBE, designed a mortar for the infantry that would not only bear his name, but would become the baseline for most infantry mortars for the next century.
The “Stokes Mortar” was a simple steel tube, of roughly three inches in diameter (it was actually 3.2 inches, or 81mm, in diameter). A simple, muzzle-loading design, the Stokes could be rapidly loaded and fired, dropping a steady stream of explosive rounds, up to twenty-five per minute, out to roughly 800 yards. The “bombs”, as the rounds were termed then, used a simple impact fuse…something that could problematic if the ground it landed on was soft or muddy. Aside from that, the Stokes Mortar was an excellent weapon for its time, and the design was quickly copied and deployed by armies around the world, with many armies immediately trying to improve the design.
The main improvement that stuck all around the world was to make the ammunition more aerodynamic in shape, vaguely similar to the “Spitzer” bullet, first developed in 1898 to get the optimal performance from the new smokeless powder that was replacing the old type of gunpowder for rifles. This was coupled to “booster charges” – doughnut-like rings filled with powder that provide additional pressure and velocity to the mortar bomb when it is fired – that increased the range significantly; in the modern day, a garden variety 81mm tube can throw rounds out to nearly three miles (4.6km+).
Tactically, this gave the infantry a powerful tool. Usually deployed at the company level, mortars provide immediate, fast-shooting fire support, able to hurl large amounts of explosives at enemies from behind cover, at short notice, without the need to call to a higher level.
Mortars in the 60- to 81mm range are reasonably light in weight, and can be broken into “man-portable” loads (which are still extremely heavy) for units without vehicles. Larger weapons – both 120mm mortars, but also units like the automatic Russian 82mm 2B9 “Vasilek” mortar – do need to be towed, but they are still light enough to be mounted in the back of relatively lightweight vehicles.
In the “irregular warfare” sphere, analogues to the Stokes Mortar can be built in home workshops with relative ease (NB: This is NOT an encouragement to break the laws in your area; you are on your own, there), but the crippling aspect for do-it-yourself forces lays with the ammunition: although relatively simple in design for the modern day, mortar ammunition requires large amounts of explosives to make any useful quantity. This is such a daunting prospect, that guerrilla armies usually don’t bother with making their own weapons and ammunition, relying on stealing (or, “liberating”, depending on your viewpoint) heavier weapons and ammunition, or buying them on the black market…This is, however, slowly beginning to change.
A major issue with modern “dismounted” mortars is that the recoil of firing the weapon tends to pound it into the ground, continually altering the angle of the tube, which requires continual adjustment to keep the weapon on target. Mounting mortars in vehicles – or on boats – helps to correct this, but the mortar still requires more attention to its sighting controls than conventional cannons and howitzers. In recent decades, serious efforts have been made to develop precision-guided rounds for mortars; and some of them actually work. They remain only a limited option, however, because of their expense – a very serious concern that NATO is discovering has not gone away through “creative financing”.
Another serious issue for dismounted mortars on the modern battlefield is “battlefield radars”. These types of radars have been deployed since the late-1950’s to detect and track artillery rounds as soon as they are fired, allowing “counter-battery” fire (i.e., using your own artillery to directly attack the enemy’s artillery) to become vastly more effective. These units have been steadily shrinking in size, while becoming increasingly capable as technology improves. While unlikely to be encountered in the hands of guerrilla forces and small-sized, poorly equipped armies, that window is slowly closing.
For all of the foregoing, however, mortars remain the “go-to” heavy weapon for infantry companies and battalions around; indeed, in Africa, mortars are essentially the “heavy artillery” for most of the continent’s armies.
Modern mortars are now well over a century old. Better materials, fuses and targeting system have come and gone, but the basic, hand-loaded steel tube throwing a large explosive round that the infantry can easily carry with them has not disappeared – and will not – most likely for another century.
“Old” does not mean “obsolete”.
