If this route was used, it would be preferable for strike aircraft of No. 18 Group RAF to attack the destroyers as Norway's inshore waters were protected by naval mines and coastal batteries. Alternatively, the German ships could make a high-speed night passage outside of the coastal islands. In case an offshore route was used, Moore ordered Vice Admiral Frederick Dalrymple-Hamilton, the commander of the 10th Cruiser Squadron, to sail with the cruisers Diadem and Mauritius and patrol off Bergen. The Home Fleet did not have any destroyers available to accompany Dalrymple-Hamilton's force, though Moore considered but decided against cancelling the carrier operation in order to make some of these ships available. Action Contrary to British expectations, the commander of the 4th Destroyer Flotilla, Captain H.F. von Wangenheim, chose to take the faster route outside of the coastal islands. On the evening of 27 January, the destroyers were spotted and attacked by British aircraft whilst west of Sognefjord, but continued their voyage. Contact was made between the two naval forces at 00:48 am on 28 January. At this time, the 4th Destroyer Flotilla was proceeding south and was located about southwest of the Utvær lighthouse and northwest of Bergen. The sea was calm and visibility was excellent due to a full moon. The British and German forces spotted each other simultaneously; at the time the cruisers were about west of the 4th Destroyer Flotilla. Upon sighting the destroyers, the British ships fired star shells to illuminate the area and turned to the south on a course parallel to that of the German ships. Z31 suffered extensive damage early in the engagement. She was struck by seven shells, which caused her to catch fire, damaged the hydrophone compartment and torpedo transmitting stations and destroyed her forward gun turret. Z31s speed was not affected but 55 sailors were killed and another 24 wounded. After Z31 was damaged, Commander Karl Hetz on board Z34 assumed command of the flotilla. Z34 made two torpedo attacks on the British cruisers to force them to change course but failed. Z38 also tried to launch torpedoes but had to break off this attack when her funnel caught fire and a boiler tube burst. Z34 suffered a hit on her waterline during this period. After Z34 was damaged, Hetz decided to turn to the north to outrun the British cruisers. Z34 fired a third salvo of torpedoes as