'B' (iv) was an Italian convoy operation from Naples in southern Italy to Bizerte in the Vichy French North African colony of Tunisia (30 November/3 December 1942).
Departing Naples on 30 November, the convoy comprised five transports escorted by the torpedo boats Groppo, Orione, Pallade, Sirio and Uragano, joined on 1 December by the destroyers Ascari, Grecale and Maestrale. On 3 December the convoy came under air attack, and the 5,609-ton German transport Menès was torpedoed and sunk. On the same day British air-launched torpedo attacked sank three independently routed Italian transports carrying fuel in drums: these were the 1,905-ton Minerva, 1,880-ton Palmaiola and 1,459-ton Audace.
Between 2 and 4 December the German transport Ankara was escorted from Taranto to Tunis by the destroyers Alpino, Granatiere and Saetta, and torpedo boats Partenope and Perseo. On 4 December this convoy was attacked by the British submarines P48 and Seraph, which failed to hit Ankara.
On 5 December the British submarine Sybil unsuccessfully attacked the freighters Honestas and Sant’Antioco that were escorted by the torpedo boats Groppo and Orione from Tunis to Naples, which the convoy reached without damage during the evening of the same day. However, the success of British aircraft and ships in this period, operating with the carefully concealed benefit of the 'Ultra' intelligence derived from British penetration of the Italian naval ciphers, greatly exacerbated the fuel shortage that had already significantly affected the capabilities of the Axis forces in North Africa.
During the same period the Italian submarines Nichelio, Asteria, Dandolo and Giada patrolled off the North African coast but made no contact with Allied ships.