Could the cannonballs of the early 19th century have sunk the battleships of the time

At first glance, the side of the warship that sank off the coast of Acre appeared to be strong and thick, but an experiment with a unique procedure showed that even the thick side did not withstand the cannonballs

A joint experiment by researchers from the Leon Recanti Institute of Maritime Studies at the University of Haifa and "Raphael" - "Raphael Company, Advanced Combat Systems" solved the riddle that occupied the researchers from the moment they noticed the thick wooden sides of the shipwreck off the coast of Acre - were the cannonballs from it period they could penetrate the sides or not.

The ship "Acre 1" was found as early as 1966, but only since researchers from the University of Haifa began to study it about three years ago did it begin to reveal its mysteries. The first mystery concerned the origin of the ship, its time and the reason why it sank. A map drawn by a British soldier in 1799, during Napoleon's siege of Acre, led the researchers to assume that it was a British "blockade ship" - a ship that the British sank on purpose to make it difficult for French ships to enter the port.

However, another puzzle that occupied the researchers concerned the thickness of the side of the ship. According to Dr. Yaakov Kahanov, head of the research team, even at first glance you could see that the wall, which was built of oak, was unusually thick and the question that was asked was whether the cannonballs of that time were able to penetrate it at all. Firing tests of cannons and ancient ships were conducted around the world, but since this is an expensive and complicated operation, they were conducted in a small amount so that even today it is not possible to know for sure about each and every ship whether the cannonballs of that time would have sunk it or not.

Those who helped the marine researchers to solve this puzzle were the engineers of "Raphael". The special model that Rafael has makes it possible to conduct a shooting experiment on a reduced scale, which reduces the cost and allows the experiment to be controlled, measured and documented. The current experiment was conducted on a scale of 1:2 and for this purpose the university built five models of the side of the ship, well built of oak, in accordance with the archaeological findings. At the same time, at "Raphael" they prepared the bullets, the cannon from which they were fired, and measurements were also made so that it would be possible to adjust the muzzle velocities in the experiment to the velocities of the cannon balls at that time: between 100-500 meters per second.

The experiment showed that despite the strength of the side of the ship, it did not withstand the force of the cannonballs that penetrated it. It also became clear that the lower the speed of the bullet, the greater the damage to the side of the ship and the amount of wood chips that were thrown from the side of the ship, and which in reality would have caused injury to the ship's crew members. According to the researchers, the results of the experiment are of great importance to the study of the ship and the study of naval battles in this period.