Operation Rheinübung
Postwar opinion is divided on this operation. Some see it as the best attempt of the outnumbered German Navy to inflict considerable damage on the Royal Navy and the British convoy system; others consider it a 'Death-Ride' in keeping with the Nazi mentality.
The basics of the operation itself were simple. The KM had four heavy surface units available; the battleships Bismark and Scharnhorst, the heavy cruiser Prinz Eugen and the carrier Graf Zeppelin. There were a number of destroyers that would accompany the heavy ships for the first part of the operation, but these short ranged craft would then return to Norway. The preparations for the operation itself had been carried out in great secrecy; the heavy units had slipped out of port and up the coast of Norway as far as Bergen under cover of cloud and poor weather, and had in fact managed to concentrate in the fjord without having been spotted by the RAF.
Sadly, all that careful forethought was wasted. Bletchly Park had given the Admiralty news that German heavy ships were heading up the Norwegian coast, and confirmation that the Bismark and Prinz Eugen at least were involved was confirmed by a member of the Norwegian resistance. As a result, although they didn't all go to sea, the units of the Home Fleet were put at four hours readiness for steam, the Prince of Wales was hurried out of her hull cleaning in dry dock, and all boiler cleaning cancelled. The old battleships Barham and Ramilles were ordered to join two of the most valuable northern convoys; their slow speed made them unlikely to be useful in a chase, while putting them in front of a potential breakout meant they might be able to intercept.
The main force of the Home Fleet was the fleet carriers Illustrious and Formidable, the light carrier Colossus, the battleships KGV, Prince of Wales, Nelson and Rodney, and the battlecruiser Hood. A number of cruisers were also available. Coastal command was also put on alert, both to try and keep the German ships under surveillance in Norway, and then to hopefully track and attack them if they ventured out. In addition two other carriers were put on readiness to join the Home Fleet; the light carrier HMS Ocean, currently at Liverpool having just escorted in a convoy, and HMS Glorious, just finishing working up after a recent refit.
The aims of the operation was to cause as much damage and disruption to the British convoys as possible, then slip back home. The fleet would then be a constant threat to a repeat foray, and would require the Royal Navy to keep heavy units tied up in Scapa Flow as a response. This would then make them vulnerable to a heavy air raid on the base itself. The start of the operation would be the breakout from Norway. The ships would be covered for the first part of their trip by land-based Luftwaffe fighters, allowing them to proceed without having to worry about the Graf Zeppelin flying off aircraft. As this was going on, high level Luftwaffe reconnaissance planes would check Scapa Flow. If the British Home Fleet was still an anchor, then the Graf Zeppelin would conduct an air strike on the base (aided by Norwegian based bombers) as a distraction, and would then retreat to Norway, allowing the surface units to slip past to the north before the British discovered them. If the Home Fleet heavy units were at sea (especially the carriers), then the Graf Zeppelin would accompany the surface force to provide air cover and a strike capability against the Royal Navy. While the carrier could only launch a small strike, it was thought this would be adequate against the biggest threat to the breakout, patrolling Royal Navy cruisers.
While the Luftwaffe kept up a constant air patrol over the fjord to discourage the RAF, a reconnaissance Whirlwind managed to get over the ships and get a set of photographs. The results concerned the Royal Navy; they had assumed this was one or two of the German heavy ships aiming to slip out to raid, not all four. The disposition of the Home Fleet was therefore split into four parts.
First, the carrier Glorious and the cruisers Norfolk and Suffolk along with a number of destroyers would cover the Denmark straight between Iceland and the Greenland ice barrier, the cruisers deployed to the east of the carrier. Second, the carrier Colossus and her escorts would cover a light cruiser force consisting of Galatea, Aurora, Kenya and Neptune between Scotland and the Faroes. The most likely route between the Orkneys and Iceland would be covered by the fleet carriers Illustrious and Formidable with the battleships Prince of Wales and KGV, and the battlecruiser Hood. This force could also reinforce either the northern or southern force if the Germans used one of those routes. Finally the battleships Nelson and Rodney would remain at Scapa to block the escape route. They would be joined by the light carrier Ocean as soon as she arrived (she was currently escorting a convoy). The biggest worry was the weather - poor weather, not uncommon at this time of year, could allow the German force to slip past, or catch one of the light carriers by surprise. The risk was, it was felt, worth taking, as such a powerful force could not be allowed to break free into the Atlantic convoys.
In addition to the naval forces, Coastal Command was also put on alert and asked to add its reconnaissance planes to the search north of Scotland, In particular the AS-radar equipped Stirlings. There was only a small number of these available, and so far they had been kept busy on the convoy routes looking for and keeping down submarines, but it was hopes their range and radar would allow them to spot the raiding force even in bad weather. For the next few days the convoys would have to take the risk of less air cover. While the chances of them being intercepted by the German carrier was of course a risk (the RN knew, from its own experience of intercepting Condors, how vulnerable a large plane could be to fighters), the hope was that the radar would allow discovery at sufficient range to keep safely back and in range of cloud cover. Finally a squadron of SeaLance torpedo planes, normally based in East Anglia in case of an attempted invasion, were put on alert to move to Scotland at short notice to provide a strike capability off Scotland in case the German fleet attempted to slip by closer to land.
At 2100 on the 25th April, the rattle of heavy anchor chains echoed around the peace of Bergen fjord. Operation Rheinübung was finally under way.
Admiral Lutjens fleet had first headed north towards Trondheim. Reports from the Luftwaffe had indicated that the Home Fleet seemed to not be in Scapa, so he intended to keep his carrier with him. Shortly before dawn the destroyers accompanying the force were detached to Trondheim, having insufficient range to accompany the heavy ships. He intended to take the ships out through the Denmark Straight, rather than through the Iceland/Faeroes gap, as he felt this would be too heavily patrolled by British aircraft. By midnight on the 26th the ships had turned west to head directly for the Straight.
Meanwhile the British had confirmation that the force had sailed; reconnaissance over the fjord had shown the absence of the heavy ships, and it was assumed that a breakout into the convoy lanes was intended. However until more was known about what route the German fleet would take, Admiral Tovey decided there was no reason to change the disposition of his ships. The ships had left the fjord before a strike on them could be arranged; the poor weather in Norway had delayed the chance until it was too late. He had therefore moved his fleet carriers to cover the capital ships, and be ready to move north or south if the German fleet didn't take the central passage into the Atlantic. In case the Germans slipped past them in bad weather, Force H was ordered to leave Gibraltar and sail noth to take up a blocking position.
The weather on the 27th was poor, and as the British ships took up station only the ASV-equipped planes were of any use, and searches from the fleet carriers and Coastal Command found nothing. The situation was of course the same for the Germans; with no ASV equipped planes, they were operating without any aerial reconnaissance at all. The German ships were not in fact spotted until late in the evening, and not by an aircraft but by the radar of HMS Suffolk, on patrol in the Denmark straight. The large echoes on the radar set could hardly be anything other than the German force that was expected, and the cruiser radioed a sighting report even as she retired westward, keeping the enemy under contact by radar.
The cruiser had also been spotted by the German radar, and although the one, smaller echo could have been anything, the fact that it was retreating at 27 knots to keep the distance between them indicated a warship of some sort. Meanwhile Coastal Command on Iceland were asked to send out a radar-equipped Stirling to confirm the sighting; this was done at 0100, and an hour later a confirmation was received. Four large echoes (assumed to be capital ships) heaving west out of the Denmark Straight.
While a night strike from the nearest carrier, HMS Glorious, was a possibility, the poor weather made the attempt difficult. With the enemy now under observation, Tovey decided to have the carrier retire west to keep the range open (she was around 120 miles from the German fleet), in preparation for a dawn strike, when the weather might not be better but at least they would have daylight.
Lutjens had no night strike capability at all (the planes carried by the Graf Zeppelin were modified Me109 fighters and Ju87 dive bombers), so the only option seemed to be to cripple or sink the cruiser tracking them at first light, and then search for any other ships in front of him. If the cruiser was alone, he still felt he had a good chance of breaking out before other ships could intercept his force.
The strike from HMS Glorious was spotted on deck well before dawn on the 28th. The Admiralty was still uncertain as to the number of planes that the German carrier could handle. Intelligence had given the ship's displacement at around 25,000 tons, about the same as a British fleet carrier. They estimated she could be carrying up to 60 - 80 planes, probably split evenly between dive bombers and fighters (no sign had ever been found of a carrier-operable torpedo plane). Glorious was carrying 18 TBR, 18 DB and 20 fighters. The fleet carriers and the battleships had altered course to the north during the night, but they would not be in a position to send off a strike until the afternoon. The decision was made to have Glorious attack the carrier; without air support it would be relatively easy to hunt down the rest of the German force. With luck, Glorious would hit the carrier before she got her own strike off.
[note: to keep things sane, I will finish this operation before going back a few days and carrying on in the Med, otherwise its just going to get too confusing]
