He later became commander of the Submarine Squadron (consisting of the whole Italian submarine fleet); he held this role at the entrance of Italy into World War II (10 June 1940) and kept it until December 1941, directing the submarine operations of the Regia Marina in the Battle of the Mediterranean.[1][5] On 9 December 1941, immediately after writing a long report which highlighted deficiencies of the Italian submarine branch (in terms of training, technical characteristics of submarines, operational doctrine, cooperation with the Air Force), Falangola was removed from office and appointed commander of the Corps of Port Captaincies, and was replaced in command of the submarine fleet by Admiral Antonio Legnani.[6]
A fervent Fascist, after the 8 September 1943 armistice Falangola immediately spoke out in favor of cooperation with the German forces, and during meetings at the Ministry of the Navy he tried – without much success – to convince other officers to do the same.[1] He immediately joined the Italian Social Republic, and on 30 September 1943 he became Commissioner for the Navy for the Open City of Rome.[1][7] He left this office on 25 December 1943, again assuming the general command the Port Captaincies that had remained in the territory of Italian Social Republic; he held this role until April 1945.[1] His sons, Carlo and Ettore, also joined the RSI as officers in Junio Valerio Borghese's Decima Flottiglia MAS; they were employed against the Italian resistance and were both captured and executed by the partisans.[8][9]
Having joined the German troops in their retreat towards Brenner Pass, at the beginning of May 1945 Falangola gave himself up in Bolzano to the Northern Italy National Liberation Committee, which in turn handed him over to the local U.S. command, that interned him in a POW camp in Coltano, Pisa, where he remained for a short time.[1]
After his release, he was deprived of his rank by the Italian authorities for having adhered to the Italian Social Republic, and he was sentenced to four years in jail (later condoned) by a military court in Rome.[1] The sentence, however, was repealed once by the Supreme Military Court "for not having committed the crime", and then a second time for an amnesty. He was discharged from the Navy in June 1945.[1]
In 1955, his service record was reviewed and the cancellation from the rolls with loss of rank was revoked.[1] He died in Rome on 14 July 1967.[1]