On 5 January 1942, Harlinghausen was replaced by Ulrich Kessler. Kessler endured the same supply problems as his predecessor. He was unable to support the U-boats on the west side of the Atlantic, nor interdict convoy routes while anti-shipping operations turned to the Mediterranean and Arctic Convoys. Italian-designed aerial torpedoes (F5a) had proven successful in the "Regia Aeronautica" (Royal Italian Air Force) and in the "Luftwaffe", but these weapons were given to KG 26 and other units operating against shipping in the Mediterranean Sea and against the Arctic convoys off Norway. Over the course of these unfolding events from 26 July 1941 to 30 April 1942, "Fliegerführer Atlantik" shrank from 90 to 16 combat aircraft and from 25 to 20 Fw 200s. During the "happy time", known as Operation "Drumbeat", Hitler remained steadfast in his view that the priorities of German air power remained elsewhere as the naval staff pressed for more Fw 200s and the newer Heinkel He 177.