Now all roads lead to France and heavy is the tread
Of the living; but the dead returning lightly dance.
Edward Thomas, Roads

Friday, January 16, 2015

Frogmen Sink a Battleship, Part I

Part I:  The Plan and the Approach

by Brian Warhola

In the summer of 1918, as World War One was drawing to close, the Austrian Navy suffered a series of defeats at the hands of the Royal Italian Navy. The most powerful ships of the Austrian Navy retreated to the port of Pola, on the Adriatic Sea. The entrance to this harbor was protected by floating booms and barricades, designed to ensnare and destroy enemy ships. The Italian Navy made several attempts to attack the Austrian fleet at Pola but failed to breach the elaborate harbor defenses.

Austrian Battleships at Anchor in Pola Harbor

Lieutenant Raffaele Paolucci was an Italian naval surgeon who devised a plan to infiltrate the harbor at Pola and destroy the largest ships of the Austrian fleet. Although the sheltered enemy fleet seemed invulnerable to conventional attack, it occurred to Lieutenant Paolucci that he might be able to reach the Austrian ships by simply swimming to them, carrying explosives.

Paolucci consulted charts of the Pola estuary and concluded that, if he could be dropped off near the entrance to the harbor, “a swim of three kilometers would enable me to reach the objective".

Keeping his plan to himself, Paolucci began to train for the task of swimming alone into the harbor at Pola. At night Paolucci swam for hours in the lagoons of Venice, increasing his endurance until he could comfortably swim five miles without resting. As his stamina increased, Paolucci began dragging a 300-pound keg of water with him, to simulate the weight of an explosive charge he planned to take with him to destroy the enemy ships.

Lieutenant Raffaele Paolucci 
In May, confident of his ability to carry out his plan, Paolucci presented the idea to his commanding officers. He was advised of the obvious dangers attending such an undertaking but was told to continue his training.

In July Paolucci was introduced to Major Raffaele Rossetti. Paolucci learned that Rossetti had designed and built an entirely new kind of aquatic weapon, a manned torpedo that was perfectly fitted to the mission for which Paolucci had been preparing himself.

Using the long, slender shell of an unexploded German torpedo that had washed up on the Italian coast, Rossetti had built a sleek submersible craft that could be ridden through the water like a horse. Filled with compressed air that drove two small, silent propellers, Rossetti’s rebuilt torpedo was about 20 feet long, weighed one-and-a-half tons, and could carry a pair of riders through the water at a top speed of two miles an hour. At the front end of the apparatus were fitted two detachable watertight canisters, each of which had room for 400 pounds of TNT. The craft could be raised or lowered in the water by adjusting a series of control valves Rossetti had designed.

In the Italian naval shipyard in Venice, Rossetti and Paolucci practiced swimming and guiding the torpedo. “We had to be in the water,” Paolucci later wrote, “clinging to the machine, which moved slowly; we had to steer it with our bodies, and in certain cases were obliged to drag the apparatus ourselves. . .we accustomed ourselves to getting over simple obstructions and nets. . .we habituated ourselves to remaining in the water for six or seven hours at a stretch with our clothes on, and to pass ing unobserved beneath the eyes of the sentries posted along the Venice dockyard. . .we traversed the whole of the dockyard without our passage being perceived either by the numerous sentries, or by the officers in charge of them, who knew that the trial was being made.”

On the night of 31 October 31 1918 the two men and their hybrid water craft were brought within a few miles of the entrance to the harbor at Pola by a navy motorboat. Donning waterproof rubber suits, Rossetti and Paolucci slipped into the water, mounted their torpedo, and set out to sabotage the unsuspecting Austrian fleet.

Riding on the incoming tide, Rossetti and Paolucci submerged the torpedo until only their heads rose above the water’s surface. It was 10:13 p.m. as they set off for Pola. If all went well, Rossetti had calculated that it should take no more than five hours to deliver the explosives to the Austrian ships and return to the waiting Italian motorboat, which lay anchored out of sight of Austrian patrols.

As they approached the entrance to the harbor Rossetti shut off the air valve that powered the torpedo’s twin propellers. The two men then carefully guided the torpedo up to the first of the barriers that guarded the outer harbor. Enemy searchlights swept over the water, threatening to expose them to view. Each time, however, the searchlights passed over them without revealing their presence.

Major Raffaele Rossetti
Reaching the outermost barricade at 10:30, Rossetti and Paolucci found that it was made of “numerous empty metal cylinders, each about three yards in length, between which were suspended heavy steel cables". After waiting for an opportune moment, the two men lifted and pushed their craft over this obstacle, anxious that the sound of metal scraping on metal might alert Austrian guards on shore. Their struggles went unnoticed. “After great effort,” Paolucci wrote, “we got past the obstruction, when I felt myself seized by the arm. I turned around, to see Rossetti pointing to a dark shape which seemed to be advancing toward us.” An Austrian U-boat, running without lights and with only its conning tower above the water, glided past them and out into the Adriatic Sea, oblivious to their presence.

Restarting the torpedo’s motor, the two men steered slowly toward the seawall that guarded Pola’s inner harbor. While Rossetti waited in the shadow of the seawall, Paolucci swam ahead to look for the easiest entrance to the harbor. Instead, he found another obstruction, a gate made of heavy timbers studded with long steel spikes.

Paolucci swam back to Rossetti and told him what he had found. Rossetti decided to continue with the mission. The tide had turned, and the two men now fought the current, dragging the heavy torpedo up to the submerged gate.

Continued tomorrow. . .


  1. What a good story. Not only was this new to me (just how big was the A-H Uboat fleet?), but you told it as a very convincing narrative.
    I want part 2!

  2. Maybe someone will write a Roads article about the kuk Uboats? Good fictionalixed account in John Biggan's A Sailor of Austria
    Jim Patton

  3. I love the Italian Front, there are so many interesting things that happen there. It's a pity that more people do not explore it. The Italian frogmen were the most innovative in the world, brave and also stupid for some of their crazy but effective missions.

  4. There was a book I read many years ago on this subject. Forget the title. But highly interesting. Especially since the Italians carried out a similar and daring attack on the Royal Navy in Alexandria harbor in the Second World War.

  5. One of the KuK Navy's most successful submarine commanders was Georg Ritter von Trapp - as in "The Sound of Music"!