The Italian air force failed to detect the approach of the British fleet to within range of Taranto. A few lumbering flying boats came near, but were shot down by British Fulmar fighters operating under radar control. So the raid achieved complete surprise and sank half the Italian navy's battleships, altering the balance of power in the Mediterranean at a stroke. The British were lucky: after storms earlier in the week only 27 of the 90 barrage balloons protecting the ships were still in the air on the night of the attack, and the Italian torpedo nets did not extend deep enough to protect the ships properly.
