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Bismarck Alternate Propulsion

Posted: Fri Jun 03, 2016 12:04 am
by Rockeye
Hi All,

This is my first time posting on the forum but I have been a long time follower and am interested to hear your feedback. I have seen several posts suggesting that the Germans should have used diesel engines in their capital ships as opposed to high pressure/temperature steam in order to increase their operational range. This was rejected due to both weight issues and the fact that there were no diesel plants available with sufficient power.

My question is could the Germans have improved on the historical range of their steam plants by using double reduction gearing as suggested by Garke and Dulin in their book or possibly by using something more exotic like the American turbo-electric drive units or the Föttinger gears used in the WWI battlecruiser Fürst Bismarck? Likewise how significant of a range increase could be expected.

Thanks for your replies

Rockeye

Re: Bismarck Alternate Propulsion

Posted: Wed Aug 10, 2016 7:36 am
by RF
The Germans had drveloped powerful diesel engines for the Panzerschiffe in the early 1930's so there was some time to develop the level of technology required for battleship sized engine power. Maybe the development of the Hipper class cruisers was a diversion from this in the sense that alternatively an upgraded version of the Panzerschiffe could have been constructed, paving the way for a further up grade to battleship level. Time would be needed for these developments along with more focussed planning - time which the KM didn't have unless the process started immediately around the time AGS came into service..

Re: Bismarck Alternate Propulsion

Posted: Tue Aug 23, 2016 2:23 pm
by Dave Saxton
Turbo Electric propulsion was strongly considered for Bismarck and Tirpitz. It was actually part of the design at one point. It was then decided against based on the potential vulnerability of the transmission cables in the event of serious under water damage.

Diesel power was planned for and would have been used for the H-class. The H-class would have had a top speed of 29 knots and if I recall correctly the same range as the panzerschiffs.

Re: Bismarck Alternate Propulsion

Posted: Tue Aug 23, 2016 4:30 pm
by RF
That does leave the question as to whether the KM would have done better to proceed straight to the H Classe and skip the Bismarcks.

Re: Bismarck Alternate Propulsion

Posted: Tue Aug 23, 2016 7:34 pm
by Paul L
NEW diesel warships had much greater range than AGS = 9,000nm @ 19 KNOTS

http://navypedia.org/ships/germany/ger_bb_h.htm 19,000nm @ 19 KNOTS
http://navypedia.org/ships/germany/ger_bb_p.htm 14,000nm @ 19 KNOTS
https://en.wikipedia.org/wiki/P-class_cruiser 15,000nm @ 19 knots



problem with resupply was probably the motivation?

Re: Bismarck Alternate Propulsion

Posted: Wed Aug 24, 2016 3:41 pm
by Dave Saxton
RF wrote:That does leave the question as to whether the KM would have done better to proceed straight to the H Classe and skip the Bismarcks.
And skip the Scharnhorsts as well. I think it boiled down to politics and the potential reaction of the rival European powers to the building of modern, long range, 16-inch gun battleships by Germany.

Re: Bismarck Alternate Propulsion

Posted: Wed Aug 24, 2016 4:14 pm
by Dave Saxton
There was a long standing controversy in German naval circles between diesel proponents and anti-diesel factions going back to Tirpitz era. During WWI diesel was considered for the Baden class, but not until the inter war period did diesel find its way onto the training ship Bremse. There were considerable problems and this lead the anti-diesel facton to almost get the panzerschiffs to get steam power. Diesel of course had been used on smaller warships, and of course submarines, and the world merchant marine ships, so there were strong advocates for both.

Diesel propulsion was not needed as long the Reichs Marine remained only a regional force. It's advantages became manifest during world wide operations.

During 1933 the Heinrich Hertz Institute conducted an engineering study of the problems presented by the diesels on the Deutschland. Some of the problems were the vibrations affecting the firecontrol optics and computer systems, and the vibration leading to cracking of the support structures of the diesel engines. So diesel was dropped in favor of high pressure steam turbines for the time being. Apparently progress was made enough to bring diesel back for the H-class and the plan Z new construction cruisers.

Re: Bismarck Alternate Propulsion

Posted: Wed Aug 24, 2016 5:54 pm
by RF
Dave Saxton wrote: And skip the Scharnhorsts as well. I think it boiled down to politics and the potential reaction of the rival European powers to the building of modern, long range, 16-inch gun battleships by Germany.
Well, if both classes are jettisoned along also with the Hipper class, then under the Anglo-German Naval Agreement of 1934 there is scope to build five H classe battleships plus three P classe cruisers. Then also some three Graf Zeppelins as well, together with some large diesel engined Atlantic destroyers.

The British may be alarmed at this construction, but the German government would be within its rights to tell the British and also the Americans that this construction is what Britain has already agreed to.

Re: Bismarck Alternate Propulsion

Posted: Thu Aug 25, 2016 12:55 am
by frontkampfer
I think RF hit on the real issue in his post that the KM did not have the time to develop the propulsion plants needed for a long legged Navy. Because they lost their fleet at the end of WWI they were trying to catch up and be innovative at the same time. The US had years to develop the propulsion plants that ultimately made the difference in the Pacific. The KM needed to go with known quantities and I think they got close with Bismarck but that was it. My 2 pfennig.

Re: Bismarck Alternate Propulsion

Posted: Thu Aug 25, 2016 2:59 pm
by Dave Saxton
The Bismarcks were only short legged in comparison to the USN fast battleships, which were designed for operating in the vast Pacific Ocean. Bismarck and Tirpitz had greater range than all other European battleships save Scharnhorst and Gneisenau. From Battleship Bismarck page 35:
(Bismarck's) maximum fuel capacity was 8,700 tons which gave her an operating range of 8,900 nautical miles at a speed of 17 knots, 9,280 nautical miles at at 16 knots. This was remarkable range for a turbine ship of the day, and it shows from the outset, the Bismarck was intended for high seas operations. However it was some 1,000 nautical miles less than the range of the proceeding Scharnhorst class of turbine battleships...
By way of comparison, Vanguard's range is listed as 8,250 nm at 16 knots.

Bismarck and Tirpitz also had greater range than Yamato and Musashi.

At sustained speeds exceeding 20 knots, the Tirpitz, during Operation Sport Palace during march 1942, demonstrated a surprisingly low fuel consumption.

It was the reliability and durability of the German steam turbine plants that was the main problem rather than range. Scharnhorst suffered from breakdowns and failures through out its career. (I am firmly convinced that it was a mechanical breakdown that did in the Scharnhorst during the Battle of North Cape.) During Sport Palace the Tirpitz suffered a partial breakdown that reduced its maximum speed by 2 knots. (it still managed to work up to 29 knots during the Albacore attack) Repairs were made after the operation at Bodo Fjord. German destroyers had a long history of problems with their high pressure steam power plants.

I have read a 1942 engineering study highlighting the problems and the fixes. Scharnhorst did not have the necessary work completed before it was sent North in early 1943. It was planned to bring Tirpitz back to Germany to remedy these problems with a proper dock yard refit after disappointing speed trials in Summer 1943. Because of the X-Craft attack this was never done.

Re: Bismarck Alternate Propulsion

Posted: Thu Aug 25, 2016 6:15 pm
by RF
Dave Saxton wrote: Bismarck and Tirpitz had greater range than all other European battleships
Yes, but...... the British and French had vast colonial empires and naval bases all over the world. Germany didn't, not even in WW2.
Italy only operated in the Medi

So Germany in effect was stuck with strategically short ranged heavy ships..... Its enemies weren't.

Re: Bismarck Alternate Propulsion

Posted: Fri Aug 26, 2016 1:27 am
by frontkampfer
"It was the reliability and durability of the German steam turbine plants that was the main problem rather than range."

Dave,

I agree totally. I think if given time and with good planning the KM could have worked out the reliability issues. They had neither.

Re: Bismarck Alternate Propulsion

Posted: Fri Aug 26, 2016 2:01 pm
by Dave Saxton
frontkampfer wrote:"It was the reliability and durability of the German steam turbine plants that was the main problem rather than range."

Dave,

I agree totally. I think if given time and with good planning the KM could have worked out the reliability issues. They had neither.

Agreed. The planning was scattered with none of the various new weapons programs and platforms able to reach maturity before war came. There were diesel propulsion and steam propulsion programs running in parallel, for example, and both still required considerable development. There were two different 28cm guns, a 35cm gun, then a 38cm gun, then a 40.6cm gun, and several different AA gun systems, with no standardization from a re-supply or ease of production perspective.

Many of the problems concerning the advanced high pressure steam systems came from not utilizing certain strategic materials that may be hard for Germany to obtain if blockaded during a war. But tough war experience taught that corners could not be cut there.

Re: Bismarck Alternate Propulsion

Posted: Fri Aug 26, 2016 2:04 pm
by Dave Saxton
RF wrote:
Dave Saxton wrote: Bismarck and Tirpitz had greater range than all other European battleships
Yes, but...... the British and French had vast colonial empires and naval bases all over the world. Germany didn't, not even in WW2.
Italy only operated in the Medi

So Germany in effect was stuck with strategically short ranged heavy ships..... Its enemies weren't.
The Germans did practice re-fueling and re-supply at sea. Ultra put an end to that though.

Re: Bismarck Alternate Propulsion

Posted: Fri Aug 26, 2016 3:04 pm
by Paul L
Dave Saxton wrote:
RF wrote:
Dave Saxton wrote: Bismarck and Tirpitz had greater range than all other European battleships
Yes, but...... the British and French had vast colonial empires and naval bases all over the world. Germany didn't, not even in WW2.
Italy only operated in the Medi

So Germany in effect was stuck with strategically short ranged heavy ships..... Its enemies weren't.
The Germans did practice re-fueling and re-supply at sea. Ultra put an end to that though.

how so? most of the supply ships were discovered accidentally since KM conceded the N Atlantic and RN had many more cruisers to search with.Meanwhile another network continued undetected until spring 1944 , while Raeder was prepping a follow On network for the next sortie after Rheinubung - in late 1941.

Ultra did have periodic success after each raid on weather ships greatly speeded up decoding times, but that never lasted for more than weeks/months at a time.