'Wikinger' (i) was a German naval operation over the Dogger Bank by Fregattenkapitän Fritz Berger’s 1^st Zerstörer-Flottille (19/22 February 1940).

The operation was beset by a wholly inadequate level of inter-service communication and co-operation between the Kriegsmarine and the Luftwaffe, and in combination with a real lack of operational experience this led to the loss of two German ships through 'friendly fire' bombing and mines. No Allied force was involved.

By a time early in 1940, the Kriegsmarine had grown suspicious of the activities of British fishing vessels around the Dogger Bank, and reconnaissance flights by Luftwaffe aircraft indicated the presence of British submarines. The Kriegsmarine thus decided to intercept the British vessels with the six destroyers of the 1^st Zerstörer-Flottille: Friedrich Eckoldt (leader), Richard Beitzen, Erich Koellner, Theodor Riedel, Max Schultz and Leberecht Maass, escorted by Luftwaffe fighters.

At about the same time, General Hans Geisler’s X Fliegerkorps of Generaloberst Albert Kesselring’s Luftflotte II planned to undertake a postponed anti-shipping operation over the North Sea by two Staffeln of Heinkel He 111 bombers of Oberstleutnant Hans Hefele’s II/Kampfgeschwader 26.

Denied its own air major air component, the German navy was thus dependent on the Luftwaffe for air support, which nonetheless remained under direct Luftwaffe rather than Kriegsmarine control, and as a result was almost inevitably bedevilled by lengthy and often ambiguous exchanges of information, plans and requests.

'Wikinger' (i) started shortly after 19.00 on 19 February as the flotilla steamed at high speed through a cleared channel between German defensive minefields, and without the requested fighter cover. In the prevailing sea and weather conditions, the destroyers were clearly visible as a result of their large white wakes, but the destroyers wished to clear the mined area as quickly as possible. The flotilla was passed twice by a German bomber, which was uncertain of the ships' status and so made no recognition signals. As a result, the German aeroplane was taken to be a British machine and engaged by the ships' anti-aircraft guns. The bomber’s crew returned fire, and both the German naval and air crews thus became convinced that British warships and warplanes were operating in the area.

On its first bombing run, the He 111 dropped three bombs, one of which struck and damaged Leberecht Maass. While the rest of the flotilla was ordered to continue, Friedrich Eckoldt went alongside Leberecht Maass to offer assistance. The bomber then made another attack, and on this occasion two bombs hit Leberecht Maass, which was broken in two by large explosions. The bomber then returned to base.

Immediately after the explosions, the remainder of the flotilla attempted to rescue the flotilla leader’s crew. Just after 20.00, Max Schultz exploded and sank, probably after striking a mine. There followed great chaos characterised by many erroneous reports of air attack, submarines detected and torpedoes fired as the surviving German destroyers dashed back and forth. Theodor Riedel dropped depth charges on a supposed submarine, and the explosions temporarily jammed her rudder. After 30 minutes of total disorder, the flotilla commander ordered the surviving four ships to return to port.

There were no survivors from Max Schultz and only 60 from Leberecht Maass: in all, therefore, 578 German sailors died.

The initial view of Generaladmiral Alfred Saalwächter’s Marinegruppenkommando 'West' naval command in Wilhelmshaven was that the flotilla had run into a German minefield, and the presence of British submarines was discounted. Then at 23.00 the naval command received a report from the X Fliegerkorps that one of its aircraft had bombed and sunk a ship in the general area of the navy’s operation. Neither the destroyers nor the Luftwaffe squadrons had been told of the other’s presence, although information had been passed to the relevant commands. By the time the risks became apparent, it was too late to advise aircrews.

A subsequent sweep of the area found some British mines, which had been laid on 9/10 February by the ships of the 20^th Destroyer Flotilla and were thus active.