At the outbreak of war, the SMS Konigsberg a cruiser in Admiral von Spey’s squadron in the Pacific, was a principal concern of Admiral King-Hall on the Royal Navyâs South Africa station.
The Konigsberg left Dar-es-Salaam, German East Africa on 31 July 1914, tracked by a combination of three British warships: Astraea, Hyacinth and Pegasus. Admiralty correspondence shows that on 1 August 1914 the Konigsberg slipped her escort as âit was not possible to shadow her for any time as Hyacinth had very little coal, and with the fuel (patent) in use, could not get more than 16 Knots at full speedâ (ADM 137/8). The availability of coal and its quality would affect both the Konigsberg and the British ships, limiting the effectiveness of their operations.
Within days she was off Aden and was threateningly placed in the shipping lane of freighters heading for the Suez Canal. Raiding the key shipping route from India to Britain via the Suez Canal was seen as a way to disrupt the British war effort and destroy key supplies. Max Looff, the Konigsbergâs captain would need to replenish fuel supplies by raiding merchant ships. Â A problem he faced was that the merchant ships were mainly carrying inferior coal which often could not be used. An example of was Looffâs capture of the City of Winchester near Aden on 6 August 1914, which was carrying inferior Bombay coal (ADM 137/9).
No contact was made with the Konigsberg until 20 September 1914, when the Admiralty received a telegram from Zanzibar at 7.30 am: Konigsberg reported not damaged, Pegasus sunk. The Pegasus had been in Zanzibar harbour to repair engines and for cleaning down, when the Konigsberg carried out the surprise attack. The Pegasus returned fire but fell short and was severely damaged within several minutes. The correspondence shows that the Admiralty then realised that the Cape squadron needed be strengthened by two or three swift light cruisers of the Konigsberg type, so that they could protect convoys and locate and destroy the German cruiser (ADM 137/9).
The documents show that from October 1914 that the Konigsberg was sheltering deep within the Rufigi River delta, over 100 miles south of Dar-es-Salaam. The Rufigi River splits in to many branches, before entering the sea, forming a vast delta of some 100 square miles. The channels are in nearly every case unnavigable for any but the lightest draft boats. It was a position which rendered attack most difficult, as only shallow draught ships could approach close enough to attack (ADM 1/8402/416).
After the sinking of the Pegasus, the Konigsberg had been pursued by HMS Chatham to the Rufigi River; on 22 November 1914 the recently commissioned Flight Sub-Lieutenant Cutler of the Royal Navy Air Service (RNAS) used his hydroplane to carry out the first aerial reconnaissance. The Konigsberg was located at least seven or eight miles within the delta. Engine failure forced Cutler to land near the Konigsberg and was taken prisoner.
In December 1914, it was evident that operations against the Konigsberg were stalled. The RNAS was asked to carry out a further mission. In spite of various technical difficulties, the first reconnaissance fights took place on 25 April 1915, when the Konigsbergâs position was photographed. In May HMS Chatham was withdrawn and replaced by, two monitors, HMS Severn and Mersey, which were designed to operate in shallow waters, arriving in the area 3 June, shortly followed by aircraft based on the recently captured Mafia Island (AIR 1/674/21/6/86).
The attack was fixed for 6 July 1915 as the most appropriate date in terms of tides and monsoon season. The attack began as an aircraft carrying bombs took off from Mafia Island shortly after 5am This was to divert attention as the monitors entered the northern channel of the Rufigi (CAB 45/218).
The two monitors took up their prearranged positions, just east of the island of Gengeni, while the RNAS began to drop bombs from a height of 6,000 feet that exploded close to the ship (AIR 1/674/21/6/86). At about 7:30am, the Mersey was hit twice and was forced to move out of range. At about 7:55am the Severnâs guns hit their target, apparently knocking out the Konigsbergâs forward gun. Both of the British ships continued to fire during the day, but nothing further was achieved and it became apparent that a second operation would be necessary (CAB 45/218, AIR 1/674/21/6/86).
On Sunday 11 July the second attempt to destroy the Konigsberg began at 11am. The Severn took up an attacking position, while the Mersey drew the Konigsbergâs fire. The Konigsberg continued to fire salvoes from four guns until 12:42, but within a further 20 minutes the guns had been disabled (AIR 1/674/21/6/86). The British ships continued their barrage until 2.20pm, by when it was obvious that no further action was necessary (CAB 45/218). Captain Looff noted that the ship was scuttled around sundown and that ‘SMS Koenigsberg is destroyed, but is not conquered’ (ADM 137/4297).
The destruction of the German light cruiser Konigsberg in the Rufigi delta during July 1915, although only a minor naval operation, was unique in character. It is an early example of cooperation between aircraft and warship in attacking a target which could not be directly sited (AIR 1/674/21/6/86). The incident was also significant, as it left the Royal Navy in effective control of the Indian Ocean.