As opposed to threads where WWII ships are teleported back in time to fight at Jutland? It's just a scenario put forth for discussion and one that "could" have occurred.
Could Yamamoto have pulled off an even more devastating PH attack?
- Thread starter steel_captain
- Start date
Those threads tend to be in ASB for a reason, and as such aren't held to the same type of accuracy as threads in this section, I mean leaving aside the points raised here already, whats the impact on the Southern front if all this effort is being expended at Pearl?
Oahu had 4 x 16" (M1919) guns with a range of about 40,000 yards. AFAIK, these were not casemated at the time of the Pearl Harbor attack, they were out in the open and vulnerable to bombing. One assumes that if a battleship attack is in the offering, these guns would have to be destroyed by dive or level bombers. I don't think either the 12" (M1895) guns or the 14" (M1907) guns had the range or the hitting power to seriously interfere that much with battleships. The 8" guns (M1888) were rail mobile, but 8" was too light to fight battleships. Incidentally, 8 of these were deployed to Luzon and after the Japanese invaded, were sent north to bombard the Japanese landings there. Japanese air attacks chopped them up, destroying 6 out of 8 guns. That was the problem with rail artillery - too vulnerable to air attack.
Ninja'd! Twice!
The Japanese BBs are going to want their spotter planes to correct fire, since they will not have line of sight to their targets inside the harbour. So they had better have done a good job of blowing up all the American fighters on the runway. The American BBs and coastal artillery would also benefit from spotter aircraft, but the coastal artillery would have their own fire control. Not sure if the BB masts would stick up over the intervening terrain for the the spotting tops to be effective or not, but the army forts could perhaps correct the BBs fall of shot by radio or telephone (Does that sound like too much Army-Navy cooperation on the first day of the war? Maybe.)
The US Navy BBs inside the harbour may or may not be able to fire broadsides, depending on how they are moored, whether they have repositioned since the initial attack, and the angle of approach of the Japanese battle line. The BBs in harbour had between them 56 x 14" and 16 x 16" guns, but only half may be able to fire depending on the angle of approach of the Japanese battle line. (Pennsylvania was disarmed while in drydock)
The Japanese BBs are faced with a dilemma. The farther away they shoot from, the more shots will go wild and land in the mud of the harbour, or dig a hole in some random hillside. But the closer they come, the more accurate the American fire will be.
Max range of Nagato and Mutsu's 16" guns was 42,000 yards for AP and 33,000 yards for HE
Max range for the Kongos's 14" guns was 38,770 yards.
At 45,000 yards the Japanese would be in peril from the 4 x 16"/50 M1919guns of the coastal artillery at Fort Barrett and Weaver.
At 38,000 yards the Japanese would be in peril from 24 x 14"/50 guns of Tennessee and California
At 36,000 yards the Japanese would be in peril from 8 x 16"/45 guns of Maryland and West Virginia
At 30,000 yards the they would be in peril from the 2 x12" coastal artillery guns of Fort Closson on Long Rang barbette carriages
At 25,000 yards they would be in peril from the 2 x 14" coastal artillery guns of Fort DeRussy on disappearing carriages
At 23,000 yards " " 4 x 8 " railway guns of Brown Camp
At 24,000 yards " " 32 x 14"/45 of Arizona, Nevada, and Oklahoma Correction: these guns were upgraded to a range of 36,000 yards in the 30's
At 19,000 yards " " umpteen 155mm guns on Panama mounts at various forts
At 18,000 yards " " 2 x 12" coastal artillery guns of Fort Kamehameha on disappearing carriages
At 14,000 yards " " 20 x 12" coastal defence mortars of Forts Kamehameha and Ruger
More guns can shoot at shorter ranges, but it would be even crazier for the Japanese to close any more.
Because of the ranges involved, any hits that land will be on the deck armour of the ships involved.
If the Japanese BBs get involved in trying to silence the shore batteries, that is the best possible scenario, because A) they are hard to hit and destroy and B) That means the Japanese will not be shooting at anything more important.
The Harbor Defenses of Pearl Harbor, Hawaii - Coast Defense Study Group
FORT BARRETTE / Kapolei /1934- / city / county park / KKK Hatch / 2/-16"/ BCLRN / 1934-1948 / casemated-WWII FORT WEAVER / Puuloa / 1899 (1922) / Navy Housing / K Williston / 2-16"/ BCLRA / 1924-1948/ ARF, destroyed AMTB No. 1 / 2-90 mm/ F / 1943-1945 Weaver / 4-155 mm / PM
cdsg.org
The Harbor Defenses of Honolulu, Hawaii - Coast Defense Study Group
FORT RUGER/ Diamond Head/ 1906-now/ Natl. Guard , State Civil Def., State Dept. Land & Nat. Res. / KK Harlow/ 8-12"/M /1910-1943 Birkhimer/ 4-12" /M /1916-1943/ rebuilt, site modified Granger Adams/ 2-8"/ BC/ 1935-1946/ Black Pt., destroyed #407/ 2-8"/ BCLRN/ 1942 NA/ tunneled into rock S.C...
cdsg.org
Last edited:
Everything still happens but possibly a bit later than in OTL however it is what happens to LEXINGTON & ENTERPRISE in this scenario which matter most and that has yet to be discussed
Except coastal guns can fend off many times their numbers in naval artillery, due to all the aforementioned factors enhancing their effectiveness. Recall Wake Island:
Six 5" guns, against two light cruisers and six destroyers - and the guns sank an enemy destroyer all on their lonesome.
There's also the Dardanelles. Which, admittedly, is the last of the noteworthy actions between coastal artillery and warships during the World Wars.
Dive bombers do surprisingly poorly against coastal artillery due to how small a target they present. The USN tested this - I remember finding a contemporary journal on coastal artillery from the 1920s (which I have been sadly unable to find again) explaining that even dive bomber accuracy wasn't really enough to take out coastal guns. And if dive bombers don't have the accuracy level bombers sure as hell don't.
For ranges I'll defer to YYJ. But I should note that if the Japanese are shelling Pearl Harbor they need to get closer to shore than they would if they were fighting the forts. Further, their preferred battle range was 22,000 yards, far below their maximum ballistic range.
Recall that two of the KB carriers are with the IJN BBs so let's let them take out those batteries. Hopefully at least 80% of the aircraft on Oahu are taken out in that initial wave since they are the primary targets so spotting aircraft have a much easier time with calling the shots falling.
Battleship Row is pretty much pointed to the south which is where the IJN BBs will be firing from so no broadsides from them if they can fire off many salvoes as it is. The US BBs cannot maneuver inside PH if they manage to even get underway.
Lastly, on the part of the American forces that morning "chaos rules"...no coordination of any kind between anybody
Sekhmet_D
Kicked
Myth.
The oil tanks and repair shops would have been difficult enough for multi engine land based bombers to take out.
For Kido Butai's carrier bombers, it would've been impossible.
There is a problem this scenario has in common with Operation Sealion scenarios. The proposed solution to many Sealion problems is that tHe LUfTwAfE blows everything up. But, the task list is too long for the forces at hand. So if the dive bombers of the 2 CVs allotted by the OP to support the battle line shore bombardment and are busy trying to suppress the coastal artillery, (which is actually a hard thing to do), they are not available to be armed for attacking the US carriers that may be lurking somewhere, or bombing whatever other ground targets the OP gives them. The B5Ns could be level bombing something, but then they will not be armed with torpedoes as a counterstrike force. The Zeros will need to be on CAP over the carriers, plus defending the battleships and their spotter planes from any surviving US Army fighters (since the CVs are not going to be in line with the BBs, who are shooting it out with the coastal artillery.) Plus the Zeros will be wanting to shoot down any US Army and Navy artillery spotter planes, overtop of the US AAA umbrella. And some IJN planes will want to be scouting out to sea in every direction so the lurking American carriers don't surprise them. Scouting is the domain of IJN cruiser float planes, but the OP does not give this force any. And the battleships float planes will be busy spotting.
I notice the tasks being given to the two CVs have grown to include destroying the fleet maintenance facilities, on top of the list above. Why not add destroying the fuel supplies? We are going to need something like an 8th airforce 1000 bomber raid. Is the whole KB hanging around off the coast of Hawaii? For how long? Remember that once the surprise is gone, the AAA is going to be heavy, everywhere.
I notice the tasks being given to the two CVs have grown to include destroying the fleet maintenance facilities, on top of the list above. Why not add destroying the fuel supplies? We are going to need something like an 8th airforce 1000 bomber raid. Is the whole KB hanging around off the coast of Hawaii? For how long? Remember that once the surprise is gone, the AAA is going to be heavy, everywhere.
Last edited:
Also, I count 30 US Navy destroyers (full destroyers retaining their torpedo armament) and 4 submarines, plus 12 destroyer minesweepers with no torpedo armament. Shaw, Cassin and Downs are not considered sunk in this scenario, but they are all in drydock, so not available. Some of the US destroyers are 4 stackers, meaning they will be armed with Mark 8 torpedoes that actually work. The Mark 14 torpedoes of the other destroyers may rarely explode, but still a torpedo attack charge by 30 destroyers might throw off the aim of the BBs on shore bombardment duty.
The tank loss would be a short term issue at worst.
The USN would take time to rebuild the tank capacity to pre-attack levels, but they are relatively simple structures and could be replaced pretty quickly. The immediate loss of oil storage would mean it would take longer for the USN to begin moving damaged ships to the East Coast for repair or to sortie the remaining ships but only by a few weeks as they began to divert/direct tankers to Hawaii. There would also be some civilian oil storage capacity as pearl Harbour had a civilian port as cargo ships would need refuelling when they visited the Islands and the USN would immediately commandeer those stores on the afternoon of the 7th December.
No doubt it would severely limit operations from Pearl directly after the attack but it's not likely to be completely stop USN operations.
Alan Zimm's book "Attack on Pearl Harbor" covers the fact there was plenty of fuel at Pearl with the underground tanks being in operation and other thing having been done but not talked about because of security.
Here is a link:
Here is a link:
Attack on Pearl Harbor : strategy, combat, myths, deceptions : Zimm, Alan D. (Alan Douglas) : Free Download, Borrow, and Streaming : Internet Archive
464 p., [16] p. of plates : 24 cm
archive.org
For comparison purposes it is worth noting that the longest range hit by a battleship in history was HMS Warspite hitting Giulio Cesare at 26,000 yards. Warspite's 15" guns' maximum range was 32,300 yards, so the record setting single hit on a battleship was at 80% of the firing gun's range. Accuracy varies with every model of gun, and this proviso applied to both sides. Coastal artillery guns are considered to be more accurate, becausse they are not moving.Ninja'd! Twice!
The Japanese BBs are going to want their spotter planes to correct fire, since they will not have line of sight to their targets inside the harbour. So they had better have done a good job of blowing up all the American fighters on the runway. The American BBs and coastal artillery would also benefit from spotter aircraft, but the coastal artillery would have their own fire control. Not sure if the BB masts would stick up over the intervening terrain for the the spotting tops to be effective or not, but the army forts could perhaps correct the BBs fall of shot by radio or telephone (Does that sound like too much Army-Navy cooperation on the first day of the war? Maybe.)
The US Navy BBs inside the harbour may or may not be able to fire broadsides, depending on how they are moored, whether they have repositioned since the initial attack, and the angle of approach of the Japanese battle line. The BBs in harbour had between them 56 x 14" and 16 x 16" guns, but only half may be able to fire depending on the angle of approach of the Japanese battle line. (Pennsylvania was disarmed while in drydock)
The Japanese BBs are faced with a dilemma. The farther away they shoot from, the more shots will go wild and land in the mud of the harbour, or dig a hole in some random hillside. But the closer they come, the more accurate the American fire will be.
Max range of Nagato and Mutsu's 16" guns was 42,000 yards for AP and 33,000 yards for HE
Max range for the Kongos's 14" guns was 38,770 yards.
At 45,000 yards the Japanese would be in peril from the 4 x 16"/50 M1919guns of the coastal artillery at Fort Barrett and Weaver.
At 38,000 yards the Japanese would be in peril from 24 x 14"/50 guns of Tennessee and California
At 36,000 yards the Japanese would be in peril from 8 x 16"/45 guns of Maryland and West Virginia
At 30,000 yards the they would be in peril from the 2 x12" coastal artillery guns of Fort Closson on Long Rang barbette carriages
At 25,000 yards they would be in peril from the 2 x 14" coastal artillery guns of Fort DeRussy on disappearing carriages
At 23,000 yards " " 4 x 8 " railway guns of Brown Camp
At 24,000 yards " " 32 x 14"/45 of Arizona, Nevada, and Oklahoma
At 19,000 yards " " umpteen 155mm guns on Panama mounts at various forts
At 18,000 yards " " 2 x 12" coastal artillery guns of Fort Kamehameha on disappearing carriages
At 14,000 yards " " 20 x 12" coastal defence mortars of Forts Kamehameha and Ruger
More guns can shoot at shorter ranges, but it would be even crazier for the Japanese to close any more.
Because of the ranges involved, any hits that land will be on the deck armour of the ships involved.
If the Japanese BBs get involved in trying to silence the shore batteries, that is the best possible scenario, because A) they are hard to hit and destroy and B) That means the Japanese will not be shooting at anything more important.
The Harbor Defenses of Pearl Harbor, Hawaii - Coast Defense Study Group
FORT BARRETTE / Kapolei /1934- / city / county park / KKK Hatch / 2/-16"/ BCLRN / 1934-1948 / casemated-WWII FORT WEAVER / Puuloa / 1899 (1922) / Navy Housing / K Williston / 2-16"/ BCLRA / 1924-1948/ ARF, destroyed AMTB No. 1 / 2-90 mm/ F / 1943-1945 Weaver / 4-155 mm / PMThe Harbor Defenses of Honolulu, Hawaii - Coast Defense Study Group
FORT RUGER/ Diamond Head/ 1906-now/ Natl. Guard , State Civil Def., State Dept. Land & Nat. Res. / KK Harlow/ 8-12"/M /1910-1943 Birkhimer/ 4-12" /M /1916-1943/ rebuilt, site modified Granger Adams/ 2-8"/ BC/ 1935-1946/ Black Pt., destroyed #407/ 2-8"/ BCLRN/ 1942 NA/ tunneled into rock S.C...
The OP says the bombardment happens in the evening:
This seems right, because it will take Nagato and Mutsu a good long while to close from a safe distance where they do not risk detection - to gunfire range at their maximum speed of 26.5 knots.
You can use flash and sound ranging to get an idea of the where the BB's are attacking from. Once that happens you can send some DD's and whatever small craft are available to go find them with the general idea of where they are at. Artillery, and guns of that size, give off flashes that can be seen at night from a distance and the sound also will be able to be heard for miles around the ships.
Extrapolating from the Warspite's unicorn of a long range hit, let's say the duel between the Japanese battle line and the forts will need to happen at less than 80% of the Kongo's maximum range if they want to achieve even one hit. That has the Japanese battle line at no more than 30,000 yards from their targets in Pearl Harbour. Any shells that do hit the Japanese ships are going to be falling at a pretty steep angle.
Nagato had three layers of deck armour, adding up to 6.7- 7.1" Kongo had 1.5-2.3 inches of deck armour, with additional 4" over the magazines, and I think the machinery.
The 16"/50 shell of the coastal defence guns fired a 2,110 pound shell that could penetrate 13.5" of side armour at 20,000 yards. I have no idea how that translates into deck armour penetration.
The 16"/45 2,110 lb shell can penetrate 11.5" of side armour at 20,000 yards.
The 14"/50 1500 lb shell can penetrate 5.31" of deck armour at 30,000 yards, table below.
www.navweaps.com
The 14"/45 1500lb shell can penetrate 6" of deck armour at 31,500 yards, table below.
www.navweaps.com
I imagine the 14" coastal guns were similiar to the 14"/45 naval guns.
The 12" coastal guns look similar to the 12"/35 naval gun, which has a penetration of 10.8 inches of side armour at 10,000 yards.
It would be cool if the Japanese BBs came within range of the 12" coastal defence mortars, at 14,000 yards or less. Those weird old weapons were designed to penetrate 6"-12" of deck armour. But I suppose we can only ask fo so much.
en.wikipedia.org
Nagato had three layers of deck armour, adding up to 6.7- 7.1" Kongo had 1.5-2.3 inches of deck armour, with additional 4" over the magazines, and I think the machinery.
The 16"/50 shell of the coastal defence guns fired a 2,110 pound shell that could penetrate 13.5" of side armour at 20,000 yards. I have no idea how that translates into deck armour penetration.
The 16"/45 2,110 lb shell can penetrate 11.5" of side armour at 20,000 yards.
The 14"/50 1500 lb shell can penetrate 5.31" of deck armour at 30,000 yards, table below.
USA 14"/50 (35.6 cm) Mark 7, Mark 11 and Mark B - NavWeaps
USA 14"/45 (35.6 cm) Marks 8, 9, 10 and 12 - NavWeaps
The 12" coastal guns look similar to the 12"/35 naval gun, which has a penetration of 10.8 inches of side armour at 10,000 yards.
It would be cool if the Japanese BBs came within range of the 12" coastal defence mortars, at 14,000 yards or less. Those weird old weapons were designed to penetrate 6"-12" of deck armour. But I suppose we can only ask fo so much.
12-inch coast defense mortar - Wikipedia
Last edited:
Alan Zimm's book "Attack on Pearl Harbor" covers the fact there was plenty of fuel at Pearl with the underground tanks being in operation and other thing having been done but not talked about because of security.
Here is a link:
Attack on Pearl Harbor : strategy, combat, myths, deceptions : Zimm, Alan D. (Alan Douglas) : Free Download, Borrow, and Streaming : Internet Archive
464 p., [16] p. of plates : 24 cmarchive.org
I have the book. On what page does Zimm state that any underground tanks were operational at the time of the attack?
16-inch/50-caliber M1919 gun - Wikipedia
This links shows what the open air 16" emplacements looked like. Easily seen from the air, not at all resistant to dive bomber attack.
I think there were only 2 of these, battery Randolf.
There were only a limited number of the 1760 lb Type 99 No. 80 Mark 5 AP bombs ever manufactured. Only a relative few were transported in the magazines of the Kido Butai, and they weren't particularly effective when they hit, with the one notable exception, the Arizona. This special, not mass produced, bomb only had an explosive filler weight of 50 pounds of Type 91 trinitroanisol that is less powerful than TNT. in contrast to this is the AN Mark 1 US 1600 pound AP bomb that had 215 pounds of Explosive D or TNT.
Of 48 bombs dropped, there were 10 hits, but "6 of the 10 were either duds or low order detonations. When the lower body of the bomb was shaved down to lighten the weapon, it weakened the bomb such that impact at an angle could crack open or deform the projectile." -
[B]Attack on Pearl Harbor,[/B] Zimm, p. 234