Today is the 70th anniversary of an interesting incident during the German commerce-raiding campaign. On Feb. 8, 1941 the German battlecruiser twins Scharnhorst and Gneisenau came across the "fast" transatlantic convoy HX-106 with 41 merchant ships, a scenario depicted in both Atlantic Navies (Clash of Arms) and in Bismarck (Avalanche Press). The Atlantic Navies scenario is called "Excessive Caution," but this may be a misnomer as it turns out.
I decided to try it out using the Victory at Sea naval miniatures rules by Mongoose Publishing, with models from Axis & Allies War at Sea! The Scharnhorst is shown below.
Given that mix, I'm not sure which game deserves the most credit, but I'd call it primarily a Victory at Sea game.
The unusual thing about this battle is that the Germans, despite having a powerful force, called off their approach when they discovered the convoy was being escorted by the old British battleship HMS Ramillies. Adm. Luetjens was under strict orders NOT to risk engaging any British capital ships and so the German squadron fled. This scenario explores what might have happened if the Germans risked a battle.
The two German ships have several advantages over the Ramillies, especially speed and gun range, having about a third more of each.
What they don't have is unlimited time. Given enough time the British convoy could either escape or at least disperse. The German ships couldn't just hang around at extreme range to try to pick off merchant ships. That would cause a prodigious expenditure of main gun ammunition because of the difficulty of hitting small targets at very long range. This was never the practice of German raiders. generally they closed the range enough to cause the targeted ship to stop and then finished it off with secondary guns or torpedoes. German capital ships, in fact, carried large batteries of torpedoes, in contrast to any other navy. While the game doesn't track ammo, a time pressure was added by placing the convoy 15 turns away from the board edge.
One odd thing about the scenario as presented in Atlantic Navies is that the British are given four H-class destroyers as an escort. I found this suspiciously strong, especially when I noticed that none of the British ships were named. In comparison, the same battle in Avalanche Press' Bismarck shows the convoy escorted by just one armed merchant cruiser in addition to the Ramillies. A little Google research led me to a fantastic site which provides the exact composition of every World War II numbered convoy! This revealed that not only did HX-106 never have four H-class destroyers in its escort, even the armed merchant cruiser had left by Feb. 8! The sole escort for the convoy was the battleship. On Feb. 12 a half dozen ASW escorts joined up as the convoy neared the British isles, but on Feb. 8 it was the Ramillies alone.
I decided to go ahead and leave the four DDs as depicted in the book because I thought the British needed the help, but my judgment is that they're merely a game balance/interest addition by Clash of Arms and were not actually present.
The British were faced with a dangerous approach strategy by the Germans. The Gneisenau was off to the northwest of the east-bound convoy while the Scharnhorst was due south, splitting the British response. Each battlecruiser was 38-inches from the center of the convoy, well within their extreme gun range of 45 inches.
The 41-ship convoy was represented by three "immortal" merchant ship models. As each merchant was sunk it would be immediately replaced by a new target in the same place. As about half the historical convoy was transporting petroleum of some sort, there was a 50/50 chance whether any particular targeted convoy ship was a tanker or a freighter. The four destroyers were on station at the four corners of the convoy box, with the Ramillies slightly south of the convoy.
Portraying Adm. Luetjens was Game Store Tony, while I took the British command.
The German strategy was straightforward. The Gneisenau would close on the convoy to shoot it up while the Scharnhorst kept the Ramillies busy. The destroyers would be watched, but Tony did not consider them a major threat.
I started off by peeling off three destroyers to make a run at the Gneisenau while the Ramillies turned to deal with the approaching Scharnhorst. One destroyer remained close to the convoy. The first turn the destroyers made smoke but a check of the rules revealed that the radar-equipped Germans wouldn't be hindered and so the destroyers concentrated on maneuvering instead.
The battle on the northern side went moderately well for the Gneisenau. It managed to land one 11-inch hit on a destroyer that caused some light damage (passed through, I suppose) and two damaging hits on freighters, knocking out the engines on the Kheti (a 2,700-ton freighter carrying sugar) and crippling the freighter Temple Arch (5,100 tons carrying lumber and wheat). The Gneisenau dodged a torpedo salvo from one destroyer while closing on the convoy. Unfortunately for the Germans, events on the southern side decided the action before the Gneisenau could do more.
The Scharnhorst's intention was to close within long range (for better gunnery) while staying outside of the Ramillies main battery range but the closing speed was misjudged (realistically, in my opinion) and the Scharnhorst found itself under fire from the Ramillies. The two ships spent a few turns dueling with the Scharnhorst definitely coming off the worse. While the Scharnhorst was able to land multiple hits on the Ramillies, the lack of hitting power of the German 11-inchers and the heavy armor for the old British battlewagon mitigated the damage. In four turns the Ramillies lost 8 of its 34 hull points for 23.5% damage -- significant damage but not devastating. A couple of fires were started but quickly doused and the ship's fighting ability was so far unimpaired.
On the other hand the heavy-hitting 15-inchers on the Ramillies were able to land a series of punishing blows on the Scharnhorst for 19 points of damage or 54%. Even worse, there were a couple of serious critical hits. The first one hit the Engineering Vital System, knocking out the Scharnhorst's ability to conduct damage control. This proved to be devastating when, on the following turn's critical, the Scharnhorst had its Engines Disabled, dropping its speed to zero -- and unrepairable!
At this point the Germans were defeated, as no amount of future damage to the convoy could make up for losing the Scharnhorst. We agreed that the Gneisenau would undoubtedly withdraw at high speed to avoid compounding the disaster and that the British destroyers would have called off their pursuit in order to guard the convoy. While it would tempting for the Ramillies to finish off the crippled, dead-in-the-water Scharnhorst, I believed that the realistic course of action for the battleship would be to also pull away and return to protect the convoy as well. After all, the Gneisenau was still in the vicinity and it certainly wouldn't do to risk the welfare of the convoy in order to sink the doomed Scharnhorst. And the Scharnhorst was clearly doomed, with its engines disabled and sitting just 700 miles off the coast of Canada, it would be just a matter of time before another British force arrived on the scene to finish it off.
The outcome of the battle suggests that the German high command's caution was not necessarily unwarranted. As I noted, while the Germans had a range advantage in good visibility, good visibility can't be counted on during the North Atlantic winter and extreme range gunfire was a very inefficient way to sink merchant ships. Therefore the German raiders had to risk getting closer and any misjudgment could easily bring a ship into the range of the old British ship where it's hard-hitting shells made every salvo a potential catastrophe. Any significant damage would require ending the raiding cruise at least and held the prospect of losing a capital ship. Just a few months later the Bismarck experience would show how relatively minor damage could have fatal consequences.
If I were to replay the scenario I think I'd leave out the destroyers. They were not actually present and they don't really add much to the British defenses anyway.