Trondheim area to monitor her. Due to the threat Tirpitz posed to Allied convoys in the Atlantic Ocean and Norwegian Sea, British Prime Minister Winston Churchill directed on 25 January that "the destruction or even crippling of this ship is the greatest event at sea at the present time. No other target is comparable to it". The Royal Air Force (RAF) dispatched 16 heavy bombers to attack Tirpitz at its anchorage at on the night of 29/30 January, but no damage was inflicted. No. 217 Squadron RAF was also ordered in February to prepare for a one-way mission against the battleship. This would have involved its Bristol Beaufort aircraft making an attack and the crews then parachuting over neutral Sweden or ditching into the sea. The raid was not attempted, and No. 217 Squadron returned to normal duties in mid-March 1942. Allied intelligence learned that Tirpitz was undertaking training in Trondheim Fjord on 19 February. In response, Tovey sailed that day with most of the Home Fleet to either raid the Norwegian port of Tromsø or attack Tirpitz if she put to sea. He cancelled the raid on Tromsø after the Admiralty passed on intelligence that another group of German ships was being transferred to Trondheim; these were the heavy cruisers Admiral Scheer and Prinz Eugen with three destroyers. The aircraft carrier , escorted by the heavy cruiser and four destroyers, was detached to attack these ships and four submarines took up positions near Trondheim. The carrier's aircraft were unable to locate or attack the German force due to bad weather, but the submarine torpedoed and badly damaged Prinz Eugen near the entrance to Trondheim Fjord on 23 February. Admiral Scheer was undamaged, and anchored near Tirpitz. The Admiral Commanding Battleships, Vice-Admiral Otto Ciliax, assumed command of this battle group and used Tirpitz as his flagship. Ciliax had led the German forces in the Channel Dash between 11 and 13 February, during which Gneisenau, Scharnhorst and Prinz Eugen returned to Germany from Brest, France, via the English Channel. Both battleships were damaged by mines during this operation, and were unable to be dispatched to Norway as intended. While the failure to prevent the battleships from passing through the English Channel was intensely embarrassing to the British, the German redeployment ended the threat which the warships at Brest had posed to Allied shipping in the Atlantic. Prelude Allied convoys Due to