Originally scheduled for 21 October 1940, the Taranto raid was delayed until 11 November to allow for key reinforcements to arrive and other commitments to be met. The aerial attack started with a volley of flares being dropped by Swordfish aircraft to illuminate the harbour, after which, the Swordfish formation commenced bombing and torpedo runs. Due to the presence of barrage balloons and torpedo nets restricting the number of suitable torpedo-dropping positions, many of the Swordfish had been armed with bombs and made a synchronised attack upon the cruisers and destroyers instead. The six torpedo-armed Swordfish inflicted serious damage on three of the battleships. Two cruisers, two destroyers and other vessels were damaged or sunk. The high manoeuvrability of the Swordfish was attributed with enabling the aircraft to evade intense anti-aircraft fire and hit the Italian ships. The Battle of Taranto firmly established that naval aircraft were independently capable of immobilising an entire fleet and were an effective means of altering the balance of power. The Japanese assistant naval attaché to Berlin, Takeshi Naito, visited Taranto to view the consequences of the attack; he later briefed the staff who planned the attack on Pearl Harbor.