Graf Spee trying to escape back to Germany...

Historical what if discussions, hypothetical operations, battleship vs. battleship engagements, design your own warship, etc.
alecsandros
Senior Member
Posts: 3990
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Graf Spee trying to escape back to Germany...

Postby alecsandros » Tue Apr 07, 2015 7:10 pm

Steve Crandell wrote: Wouldn't it take 10 to 15 seconds or so to even apply full rudder?

... It certainly would.
However, the time of flight of 280mm shells would be ~ 40 seconds. A cruiser moving at 30kts (15meters/second) could get out of the probable danger zone of a 3-gun salvo and even a 6-gun salvo (but AGS was firing 3-gun salvos at that phase) in 40 seconds...

dunmunro
Senior Member
Posts: 3075
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Graf Spee trying to escape back to Germany...

Postby dunmunro » Tue Apr 07, 2015 8:52 pm

ric_roc wrote:Dave,
thanks for the info on the german ORF, it is much better that what I have in the model and I will "upgrade" in my next release! It is not exactly a surprise due to the quality of the german optic industry.
Best regards,
Ric roc


GF's hit probability against Harwood indicates that GF's ranging was not all that accurate, especially given the very short ranges for much of the action.

30m accuracy at 23000m (230hm) is highly unlikely. Any document that shows that accuracy in actual use is incorrect or being misinterpreted.

ric_roc
Junior Member
Posts: 14
Joined: Tue Mar 10, 2015 3:46 am

Re: Graf Spee trying to escape back to Germany...

Postby ric_roc » Wed Apr 08, 2015 2:49 am

Based on the accounts of the battle, the Graf Spee scored rapidly on the HMS Exeter at long distance, then the quality of AGS firing has been degraded:
- AGS evasive steering
- Stress of being under fire, ( practice shooting at the range is always much more accurate! )

I am adjusting the parameters to model accuracy degradation over time. It is a personal interpretation but during the Battle of River Plate the British hits were scored when the firing unit was not itself under fire (no need for evasive steering!).
Note: I will try to cross check this theory.

Best Regards,
Ric Roc

alecsandros
Senior Member
Posts: 3990
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Graf Spee trying to escape back to Germany...

Postby alecsandros » Wed Apr 08, 2015 5:31 am

dunmunro wrote:
ric_roc wrote:Dave,
thanks for the info on the german ORF, it is much better that what I have in the model and I will "upgrade" in my next release! It is not exactly a surprise due to the quality of the german optic industry.
Best regards,
Ric roc


GF's hit probability against Harwood indicates that GF's ranging was not all that accurate, especially given the very short ranges for much of the action.

30m accuracy at 23000m (230hm) is highly unlikely. Any document that shows that accuracy in actual use is incorrect or being misinterpreted.

... Duncan,
AGS hit rate was very high in the initial 10 minutes of the action, when Exeter was crippled.

Her hate rate declined sharply to near 0% after her main and secondary command positions were repeatedly hit, radar out of action, both main directors damaged. The smoke screens and evasive manouvreing made by both sides further decreased her hit rate.

===

Nonetheless, the hit rate for the entire battle for AGS was drastically higher than Exeter's, Ajax and Achilles.

dunmunro
Senior Member
Posts: 3075
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Graf Spee trying to escape back to Germany...

Postby dunmunro » Wed Apr 08, 2015 8:58 am

Graf Spee scored 7 hits on Exeter and 1 hit on Ajax, or 8 hits out of 414 28cm rounds fired for a 1.93% hit rate.
Graf Spee fired 378 15cm rounds and scored no 15cm hits.

Exeter scored 3 hits on Graf Spee out of ~190 rounds fired for a 1.58% hit rate. All of Exeter's hits were scored in the salvos before her FC systems were knocked out so her fire was very effective when controlled by the DCT and AFCT so that Exeter and GS were scoring hits at a very similar rate. However the 28cm hits quickly degraded Exeter's firepower. Much of Exeter's 8in ammo was expended after her central FC was disabled.

Ajax and Achilles fired 823+1242 = 2065 rounds for 17 hits or .84%. Their hit rate was also lowered by FC communication problems.

GS was mainly firing HE rounds and a number of these burst on striking the water and caused splinter damage to all three RN ships. We would expect GS to have more accurate fire because of the superior ballistics of the 28cm guns but their advantage over the RN 8in seems slight.

Data on hits on RN ships from BR 1886,H.M. SHIPS DAMAGED OR SUNK BY ENEMY ACTION . Data on hits to GS from Warship Profiles Graf Spee and Exeter.

Francis Marliere
Member
Posts: 239
Joined: Mon Oct 18, 2010 3:55 pm

Re: Graf Spee trying to escape back to Germany...

Postby Francis Marliere » Wed Apr 08, 2015 9:33 am

Gentlemen,

comparing the hit rates of several ships does not always tell you which one is the best shooter because in a battle all things are not equal. A good shooter may have a low hit rate because of bad luck and/or he shoots at a difficult target (small, fast, far away, under smoke, steering evasively, etc.). A "bad" shooter may have a high hit rate because of good luck and / or he shoots at an easy target (close, large, slow, unmaneuvring, etc.). IMHO there are so many variables that it's difficult to judge. As you know, there are lies, damned lies and statistics ...

Anyway, my point of view is that a wargame should care too much about the details. A good, accurate and reliable model for gunnery, armor, damages, etc. is necessary, but one should keep in mind that it will never be perfect, it will never totally fit with what we know on naval gunnery. Moreover, the more one tries to build a "perfect" model, the more one is at risk to to forget what is really important: tactics, leadership, communications. Don't forget that in a wargame that has the ambition to be realistic, the player is in the role of an naval officer commanding a ship, a squadron / division or a fleet, not of a gunnery officer who is responsible only of the shooting of a single ship.

alecsandros
Senior Member
Posts: 3990
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Graf Spee trying to escape back to Germany...

Postby alecsandros » Wed Apr 08, 2015 9:44 am

dunmunro wrote:Graf Spee scored 7 hits on Exeter and 1 hit on Ajax, or 8 hits out of 414 28cm rounds fired for a 1.93% hit rate.
Graf Spee fired 378 15cm rounds and scored no 15cm hits.

Exeter scored 3 hits on Graf Spee out of ~190 rounds fired for a 1.58% hit rate. All of Exeter's hits were scored in the salvos before her FC systems were knocked out so her fire was very effective when controlled by the DCT and AFCT so that Exeter and GS were scoring hits at a very similar rate. However the 28cm hits quickly degraded Exeter's firepower. Much of Exeter's 8in ammo was expended after her central FC was disabled.

Ajax and Achilles fired 823+1242 = 2065 rounds for 17 hits or .84%. Their hit rate was also lowered by FC communication problems.

GS was mainly firing HE rounds and a number of these burst on striking the water and caused splinter damage to all three RN ships. We would expect GS to have more accurate fire because of the superior ballistics of the 28cm guns but their advantage over the RN 8in seems slight.

Data on hits on RN ships from BR 1886,H.M. SHIPS DAMAGED OR SUNK BY ENEMY ACTION . Data on hits to GS from Warship Profiles Graf Spee and Exeter.


... Duncan,
Graf Spee hit Exeter at least 7 times and Ajax 2 times (1 hit at 7:25 the other at 7:40). 2 more salvos produced extensive damage by splinters - 1 at 6:23 on Exeter and 1 at 6:40 on Achilles.

So the total of direct hits is 9 out of 414; if damaging near-misses are included, we have 11 out of 414 (2.65%).

According to the German reports, Exeter obtained 2 x 8" hits, not 3.

Exeter expended 177 x 8" rounds during the battle.

So the hit rate was 1.12%.


http://nzetc.victoria.ac.nz/tm/scholarl ... Epi-b.html

dunmunro
Senior Member
Posts: 3075
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Graf Spee trying to escape back to Germany...

Postby dunmunro » Wed Apr 08, 2015 10:17 am

alecsandros wrote:
dunmunro wrote:Graf Spee scored 7 hits on Exeter and 1 hit on Ajax, or 8 hits out of 414 28cm rounds fired for a 1.93% hit rate.
Graf Spee fired 378 15cm rounds and scored no 15cm hits.

Exeter scored 3 hits on Graf Spee out of ~190 rounds fired for a 1.58% hit rate. All of Exeter's hits were scored in the salvos before her FC systems were knocked out so her fire was very effective when controlled by the DCT and AFCT so that Exeter and GS were scoring hits at a very similar rate. However the 28cm hits quickly degraded Exeter's firepower. Much of Exeter's 8in ammo was expended after her central FC was disabled.

Ajax and Achilles fired 823+1242 = 2065 rounds for 17 hits or .84%. Their hit rate was also lowered by FC communication problems.

GS was mainly firing HE rounds and a number of these burst on striking the water and caused splinter damage to all three RN ships. We would expect GS to have more accurate fire because of the superior ballistics of the 28cm guns but their advantage over the RN 8in seems slight.

Data on hits on RN ships from BR 1886,H.M. SHIPS DAMAGED OR SUNK BY ENEMY ACTION . Data on hits to GS from Warship Profiles Graf Spee and Exeter.


... Duncan,
Graf Spee hit Exeter at least 7 times and Ajax 2 times (1 hit at 7:25 the other at 7:40). 2 more salvos produced extensive damage by splinters - 1 at 6:23 on Exeter and 1 at 6:40 on Achilles.

So the total of direct hits is 9 out of 414; if damaging near-misses are included, we have 11 out of 414 (2.65%).

According to the German reports, Exeter obtained 2 x 8" hits, not 3.

Exeter expended 177 x 8" rounds during the battle.

So the hit rate was 1.12%.


http://nzetc.victoria.ac.nz/tm/scholarl ... Epi-b.html


BR 1886 for Ajax states:
One Direct Hit and several Shorts with 11" A. P.O. delay action fuzed Shell.

for Exeter:
Seven Direct Hits and several "Shorts" with 11" delay and direct action fuzed Shells


Near misses cannot be included in the hit total since HE shells can cause splinter damage from a very considerable distance.

From Warship Profile 13:
Damage inflicted on 'Graf Spee'
Of the 190 plus 11in shells fired by Exeter three hit Graf Spee. The first passed through the upper part of the bridge without causing any real damage: the second pierced the armour plate of an AA gun, killing half the gun's crew, and went through two decks before exploding in the equipment for providing fresh water; the third penetrated the 140mm steel armoured belt and the starboard armoured longitudinal bulkhead before exploding amidships. This last shell, had it struck a metre lower, might have reached No 4 section of the engine room before exploding.

Commander F. W. Rasenack, a gunnery officer on board Graf Spee, commented on the surprising effectiveness of the British 8in shells which clearly belied the view that 'Grief Spee could only be successfuly fought by a battleship'.

alecsandros
Senior Member
Posts: 3990
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Graf Spee trying to escape back to Germany...

Postby alecsandros » Wed Apr 08, 2015 10:27 am

dunmunro wrote:
BR 1886 for Ajax states:


"Accordingly, at 7.40 a.m., the Ajax and Achilles altered course away to the eastward under cover of smoke. As the ships were turning, a shell from the Graf Spee cut the Ajax’s main topmast clean in two, destroyed all her aerials, and caused a number of casualties."

Near misses cannot be included in the hit total since HE shells can cause splinter damage from a very considerable distance.

"At 6.23 a.m. one shell of her third salvo burst short of the Exeter amidships. It killed the crew of the starboard torpedo-tubes, damaged the communications, and riddled the funnels and searchlights with splinters"

"At 6.40 a.m. a salvo of 11-inch shell fell short of the Achilles in line with her bridge and burst on the water. The flying splinters killed four ratings and seriously wounded two others in the director control tower. The gunnery officer was cut in the scalp and momentarily stunned. On the bridge, the chief yeoman of signals was seriously wounded and Captain Parry hit in the legs. The material damage in the director control tower was miraculously small and no important instrument was affected. After a few minutes, the control tower’s crew, in a ‘most resolute and efficient way’, resumed control from the after control position which had temporarily taken over"



From Warship Profile 13:
Damage inflicted on 'Graf Spee'
Of the 190 plus 11in shells fired by Exeter three hit Graf Spee. The first passed through the upper part of the bridge without causing any real damage: the second pierced the armour plate of an AA gun, killing half the gun's crew, and went through two decks before exploding in the equipment for providing fresh water; the third penetrated the 140mm steel armoured belt and the starboard armoured longitudinal bulkhead before exploding amidships. This last shell, had it struck a metre lower, might have reached No 4 section of the engine room before exploding.

Commander F. W. Rasenack, a gunnery officer on board Graf Spee, commented on the surprising effectiveness of the British 11 in shells which clearly belied the view that 'Grief Spee could only be successfuly fought by a battleship'.


11" shells fired by EXETER ?

Duncan, get a grip, there were 2 x 8" hits and 17 x 6" hits.
Attachments
AGS hits.png
AGS hits.png (249.76 KiB) Viewed 688 times

User avatar
Dave Saxton
Supporter
Posts: 2876
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Graf Spee trying to escape back to Germany...

Postby Dave Saxton » Wed Apr 08, 2015 3:40 pm

Millington-Drake was mistaken about hit 3 on his chart. Examination of British Intel photos taken at Montevideo don't show this hit. The German records also record only two 8" hits from Exeter's salvos 3 and 4. One was the deck hit on the AA ammo scuttle and the other was the dud that passed through the foretop tower and bounced off the upper deck on the far side and into the sea.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

dunmunro
Senior Member
Posts: 3075
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Graf Spee trying to escape back to Germany...

Postby dunmunro » Wed Apr 08, 2015 6:03 pm

Dave Saxton wrote:Millington-Drake was mistaken about hit 3 on his chart. Examination of British Intel photos taken at Montevideo don't show this hit. The German records also record only two 8" hits from Exeter's salvos 3 and 4. One was the deck hit on the AA ammo scuttle and the other was the dud that passed through the foretop tower and bounced off the upper deck on the far side and into the sea.



Exeter opened fire with her A arcs closed, so that only A and B turrets could bear. Exeter's B turret was hit (with massive splinter damage to the bridge and the DCT) just after she fired salvo 8 so that would indicate that she scored at least two hits with, at most, 16 rounds and that Exeter scored the first two hits of the action and that her initial fire was more accurate than GF's.

Hit 3 is described in great detail - it seems unlikely to be incorrect.

alecsandros
Senior Member
Posts: 3990
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Graf Spee trying to escape back to Germany...

Postby alecsandros » Wed Apr 08, 2015 7:12 pm

dunmunro wrote:Exeter opened fire with her A arcs closed, so that only A and B turrets could bear. Exeter's B turret was hit (with massive splinter damage to the bridge and the DCT) just after she fired salvo 8 so that would indicate that she scored at least two hits with, at most, 16 rounds and that Exeter scored the first two hits of the action and that her initial fire was more accurate than GF's.

Hit 3 is described in great detail - it seems unlikely to be incorrect.


... Graf Spee caused heavy damage on Exeter with salvo 3 at 6:23 and obtained the first direct hit on salvo 4 at 6:24.

The exact timing of the 8" hits on Graf Spee is contradictory between the sources that I have.

User avatar
Dave Saxton
Supporter
Posts: 2876
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Graf Spee trying to escape back to Germany...

Postby Dave Saxton » Wed Apr 08, 2015 8:44 pm

Okay, having checked my translations of Rasenack, there is a third 8" hit described by him. However, it is described a little different than in the English accounts. According to Rasenack, it passed over the belt armour (explaining the lack of photographic evidence correlating to Millington-Drake's description) and through an armoured bulkhead before exploding about 40 cm above the panzerdeck. He wrote that AGS was in a hard turn and heeling over at the time so it passed over the panzerdeck instead of striking it. He further comments that since at that range, given a 0 target angle, a 8" shell could penetrate 140mm of belt, so had it been lower at a favorable angle it may have penetrated to a machinery space, given the belt was only 60-80mm. 140mm penetration corresponds to about 20km battle range (German 8" gun), and the hard turn would likely have been the turn to avoid crossing the T of Ajax and Achilles.

and that Exeter scored the first two hits of the action and that her initial fire was more accurate than GF's.


Indeed it does. Or at least about equal to AGS's shooting. Remember AGS also scored with its 3rd or 4th salvo. Opening fire at 0617 AGS scored at least 7 hits during the next 17 minutes or so. That would be with about 102 rounds, estimated.

How many visualize this battle: a prolonged slug fest with both sides scoring hits few and far between is wrong. The first 15-20 minutes of battle was fast and furious with both the Exeter (at least before the hit on B turret) and the AGS shooting exceptionally well at ~18-20km battle ranges. At 0638 the battle turned into a stern chase for the next 40 minutes and like most stern chases high hit probabilities are not likely.

After Exeter was reduced to 2 guns under local control at 0634 it was not likely it would score any additional hits. This further indicates that Exeter scored it hits early and was shooting accurately despite the long range.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

dunmunro
Senior Member
Posts: 3075
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Graf Spee trying to escape back to Germany...

Postby dunmunro » Wed Apr 08, 2015 9:39 pm

Dave, thanks. That's very interesting info.

The accuracy of Exeter's fire is often overlooked because she suffered heavily, early on, from 28cm hits to her forward turrets. In fact, Exeter was just as likely to have hit one of GS's 28cm turrets. Had she done so, we would now all be commenting on how quickly Exeter's 8in guns crippled GS's firepower, and how quickly the battle became an overwhelming RN victory, rather than a near Kriegsmarine one, that turned into a draw.

alecsandros
Senior Member
Posts: 3990
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Graf Spee trying to escape back to Germany...

Postby alecsandros » Thu Apr 09, 2015 5:55 am

@David

Koop & Schmolke in "Pocket battleships of Deutschland class - Warships of the Kriegsmarine" give 2 x 8" hits.

Gerhardt Bildingmeier in his extensive analysis of the battle, published in Warship Profile no 4, gives 2 x 8" hits.

Please take into consdieration that relying on a single source for information (German or British or neither) is not sufficient to reconcile the matters at hand. Remember that post-battle assesment of Graf Spee's damage indicated "50-60 small and large caliber hits on the German battleship".

===

The range of the engagment and of the hits scored is another complicated matter, and I remain firm to the probability that range between AGS and Exeter was 15km at most at 6:32.


Return to “Hypothetical Naval Scenarios”

Who is online

Users browsing this forum: Bing [Bot] and 1 guest

cron