It was 11 o'clock the 18th September 1943. The two engines Isotta Fraschini "Asso 1000" of the MAS 522, destined in the Aegean, vibrated the bridge of the torpedo boat while impulsing her towards the open sea. The commander of the unit, Lieutenant Carlo Beghi, traced mentally the chart of operations that he should perform during the day trip. He was thoughtful and not without reason. When the events of the 8th September he was destined in Vazi, in the isle of Samos, in the Aegean. This island, as the surrounding terrain, was under control of the British, the Italian division "Cuneo" and, in some areas, of the Greek partisans.

The "Cuneo", led by General Soldarelli, had immediately accepted the Armistice and put itself under the command of the monarchical goverment. The 12th September Beghi had brought to Leros General Gaudioso, High Staff Deputy of the "Cuneo", and two British liaison officers. The day 17 he had accomplished a mission with his MAS 522 by transporting General Arnold, British military aggregate in Turkey. Now, the day 18, he had to transport a delegation comprised by General Pejrolo, Deputy of the "Cuneo", Colonel Pawsen and Commander Parish, British, and Admiral Levidis, of the Greek Royal Navy. The purpose of the mission was to clarify things between the Greek partisans and the Italian Black Shirts garrisoned in the isle of Ikaria, for their relations were rather tense.

Accomplished the mission, the MAS 522 headed towards Furni, where she arrived at 18:15 hours to promptly depart towards Samos at 18:30 hours. Everything seemed to run smoothly, but the delegation did not know that Beghi had no intention to return to Samos. Following his own conviction, after the Armistice he wanted to continue the war on the German side, or at least against the Allies. The crew, on mutual agreement, had joined him. Thus he waited the occasion to cross the lines, but since he had the opportunity of transporting high officers he decided to wait for the best moment to transport some very important personage, to better serve his cause.

The 18th September, in collusion with the crew, he decided the "now or never". So, around 19:00 hours, in the proximity of Cape Fanari, he inverted the course and, pistol in hand, forced the passengers to surrender as prisoners. Only Parish tried to react, with the result of being scratched by a bullet. The attempts to convince Beghi to desist were useless. That same night the MAS 522 entered the port of Zira, in German hands, where she was welcomed with the expected honors. The MAS 522 remained with the Germans during some days until the 25th September, when she was delivered to the Navy of the Italian Social Republic on which she operated under the command of Lieutenant Mistrangelo.

In the spring of 1944, also in Aegean waters, she was hit and sunk by a fighter of the Royal Air Force.