Naval History Forums

Does anybody know if the Germans (or anybody else) seriously considered using exclusive diesel engine drive for battleships?

I am not an engineer so I am not familiar with the precise technical requirements. However the Riechsmarine had the diesel technology to develop the Panzershiffe in 1931, is it feasible that they could have developed a diesel engine to power Bismarck by 1940/41?

I am aware that in 1942 the Germans did get a diesel engined destroyer on to the drawing board, I presume that like most other construction projects in wartime Germany they suffered from excessive bureacracy and shortages of labour and materials.

But in the early 1940s would a diesel driven battleship be a realistic proposition?

Yes, the best-known proposal was the "H" class.

Wasn´t Scharnhorst supposed to be powered by diesels?

The failure to provide diesels for Scharnhorst is a good indicator of the breakdown in German naval planning. The decision to go with turbines preceded the design that we know as Scharnhorst--the original Ship D also had turbines.

Admiral Graf Spee had eight set of MAN diesels!

Graf Spee was a pocket battleship!!

Not the real article!!

Tiornu wrote:Yes, the best-known proposal was the "H" class.

But the diesel engines projected weren't developed were they?

What was the largest diesel engine developed by the Germans in the war?

I think that the largest diesel engines by then were the 8000 hp from Graf Spee.

marcelo_malara wrote:I think that the largest diesel engines by then were the 8000 hp from Graf Spee.

I believe that Graf Spee had 56,000 shaft-horsepower from eight MAN engines, thats 7,000 from each engine. The Deutschland/Scheer had a similar arrangement.
The point here is that this large diesel engine facility was available to the Germans in the mid 1930's, yet they didn't develop it further. I don't know about the diesel plant in German light cruisers, I have asked about this in another topic, but the Hipper classe cruisers, torpedo boats and destroyers all used turbine plant without any attempt to develop diesel engines for these vessels (they did blueprint two versions of a diesel engined destroyer and two prototype engines built, but that was in 1944).

As far as I am aware the largest working diesel engines the Germans had, apart from those in the Panzerschiffe, were the 3,500 SHP diesel-electric engines of the type that hilfskreuzers Kormoran and I think possibly Stier had.

If anybody knows differently I'm sure they'll tell me.

For me, the big story in German diesels is not the one about the big warships but the one about the S-boat powerplants. No one else was able to come close to what the Germans achieved, and the result was the most powerful MTBs of the war.

Tiornu wrote:For me, the big story in German diesels is not the one about the big warships but the one about the S-boat powerplants. No one else was able to come close to what the Germans achieved, and the result was the most powerful MTBs of the war.

According to the articles on the Prinz Eugen website the S boats had a triple engine arrangement with up to 7,500 SHP - the standard engine had 2,293 SHP and I think was also used as the main engine for most of the U boat designs, using a double engine arrangement to give about the 4,400 SHP often quoted.

hi RF .the term pocket battleship was a british term.not a german one I belive the german name for this class of ship was Armoured cruisers,and I think BUT i'm not sure,that the 8000 hp engines in the Graf Spree was the most powerful desiels the germans built.

The Germans called them "armored ships," a term copied out of the Treaty of Versailles. The writers of the treaty were referencing a common term in North European navies for coast defense battleships like the Sveriges. During WWII, the KM dropped the pretense and rerated the ships as heavy cruisers, a much better choice.

longreach wrote: I think BUT i'm not sure,that the 8000 hp engines in the Graf Spree was the most powerful desiels the germans built.

longreach -

I'm not sure of all the details, but my references show each of the three Panzerschiffe being equipped with eight MAN 9-cylinder, double acting, two-stroke Diesel engines, four per shaft, 450 RPM, originally rated at 6650 HP normal, 7100 HP max short period HP.

In practice, each of the three ships was a little more powerful that her older sister - the learning curve worked for the Kriegsmarine as well! Deutschland displayed 6750 HP each normal rating during trials, Admiral Scheer 7100 HP, and Admiral Graf Spee even more, though I can't find a specific figure for AGS.

These Diesel engines were the most powerful in the world at the time they were put in service. They proved to be maintenance headaches - cracked cylinders & pistons and continual stuffing box problems (at the lower combustion chamber connecting rod), causing the most common troubles. When AGS entered the River Plate battle, her engines were not anywhere near optimal.

The fuel combustion also wasn't as efficient as hoped - they smoked far more than anyone predicted, much to the dismay of the Kapitan zur See of each ship during their raiding missions.

Derf

I'm not convinced that the diesels on H-39 wouldn't have imparted tremendous vibration to the entirety of the ship. Of course, I know nothing about Vulcan gearing but looking at the machinery layout of H-39 shows cumulative shaft runs equal to about 140% the length of the ship. In theory that doesn't bode well for smooth running. Any thoughts on this? With all that shafting and heavy gearing (2 vulcan gears per shaft), totaling ~ 5100 tons with the engines, I don't think a diesel-electric setup would have weighed significantly more. That's how I would have done it if I could have figured out some way to run diesels in parallel with alternating current. Easier with DC but less efficient evidently.