'T.18' was an Italian convoy undertaking from southern Italy to Tripoli in North Africa (22/25 January 1942).

On 22 January four cargo ships, in the form of the 5,322-ton Monviso, 6,339-ton Vettor Pisani, 5,324-ton Monginevro and 6,142-ton Ravallo departed Messina, and the 13,098-ton troop transport Victoria departed Naples to come together under escort of the destroyers Ugolini Vivaldi, Lanzerotto Malocello, Antonio da Noli, Aviere, Camicia Nera and Geniere, and the torpedo boats Orsa and Castore. Cover was provided by Ammiraglio di Divisione Conte Raffaele Courten’s 7a Divisione Incrociatori (light cruisers Emanuele Filiberto Duca d’Aosta, Muzio Attendolo and Raimondo Montecuccoli), and destroyers Alpino, Bersagliere, Carabiniere and Fusiliere, with more distant cover provided by Ammiraglio di Squadra Carlo Bergamini with the battleship Caio Duilio and destroyers Antonio Pigafetta, Alfredo Oriani, Ascari and Scirocco.

Despite the provision of German air support, on 24 January a Fairey Albacore torpedo bomber of the Fleet Air Arm’s No. 820 Squadron, based at Berka near Benghazi, intercepted the convoy to the north-east of Tripoli and sank Victoria: of the 1,400 soldiers on board, 1,046 were rescued and delivered to Tripoli by the destroyers Aviere, Ascari and Camicia Nera, and the torpedo boats Calliope and Perseo.

The convoy reached Tripoli on 25 January and the supporting warships reversed course and headed for Taranto. Of the British submarines on patrol in the area, P36 on 24 January missed the Italian cruisers and and was damaged in an air raid on its return to Malta on 29 January, Ultimatum on 25 January sank the 3,352-ton Italian transport Dalmatia which was sailing independently, and Upright had no success.