Dec 7, 1941. The USN is at sea. What does IJN do now?

[GrauGeist]

Pretty sure that a bomb hitting a storage tank would compromise it's ability to hold liquid, even if the liquid was water.

The third strike, which Nagumo called off, was planned to strike the Navy yard, storage facilities and the shop areas near the drydocks.

Even though Yamamoto agreed with Nagumo's decision at the time, he later admitted it was a mistake.

The Japanese had very detailed maps of the base and knew the locations of the tank farms, the attached image was found in a captured midget sub:

 

[Thumpalumpacus]

They lacked the training and armament to create any significant destruction of the naval fuel farms that contained heavy viscous and nearly inflammable bunker fuel. Aircraft 7.7mm and 20mm rounds could not ignite the fuel even if they managed to hit and penetrate the tanks. If a few GP bombs managed to hit, a gooey mess would ensue, not a firestorm. Naval bunker fuel needed to be preheated to get it to burn properly in ship powerplants, and it wasn't going to explode and burn in a chain conflagration, particularly given tank farm spacing and containment walls. The Kido Butai would need special training and specially developed incendiary munitions to attack the fuel farm. Heavy fuel oil - Wikipedia

More effective too would be cluster-bombs deploying submunitions to wreck the pumps and piping moving all that oil around the farms, but again, to your point about Japanese ammo, they had none available for the task aboard KdB.

 

[33k in the air]

More effective too would be cluster-bombs deploying submunitions to wreck the pumps and piping moving all that oil around the farms, but again, to your point about Japanese ammo, they had none available for the task aboard KdB.

Arguably, going after the important support vessels at Pearl such as the repair ships, oilers, and the destroyer and seaplane tenders, would pay a bigger dividend. Wrecking the drydocks, cranes, and similar infrastructure would have made the salvage and repair efforts in the aftermath of the attack much more lengthy and difficult.

 

[muskeg13]

Historically, air attacks intending to destroy fuel tank farms didn't produce the predicted easy results. Individual tanks, while some offered quite large targets, proved hard to hit and set alight. The fuel stocks didn't just spontaneously combust. Examples are the Kido Butai's raid on Trincomalee, Sri Lanka in April, 1942, where only one of 101 12,000 ton fuel tanks was destroyed, and that was by what may have been a suicide attack when one aircraft crashed into Tank #91. There's also the allied "Oil Campaign" of which Operation Tidal Wave (Ploiești oilfields) was a part of. There are many reasons why the anti-oil campaign only achieved success after a multi-year series of prolonged and very costly missions (for the attackers), but oil wasn't ever an easy target.

 

[Thumpalumpacus]

Arguably, going after the important support vessels at Pearl such as the repair ships, oilers, and the destroyer and seaplane tenders, would pay a bigger dividend. Wrecking the drydocks, cranes, and similar infrastructure would have made the salvage and repair efforts in the aftermath of the attack much more lengthy and difficult.

No argument here. The KdB carriers already had torpedoes for shallow waters. Hitting the doors for the drydocks would have added thousands of miles (round-trip) for any potential battle-damaged ships as they would have had to go to Bremerton or San Diego. And as noted above, the presence of repair ships in PH also meant that the base itself was able to reconstitute quicker, perhaps. I hadn't given much thought to cranes, but that's a good point as well. they're needed to lift and remove armor-plate, turrets, etc, and without them -- especially with drydocks that must themselves be repaired -- it further turns PH less effective and would slow down things like repairing Yorktown for Midway and so on.

Lots of knock-on effects from your point here.

Neosho, near California on the morning of the attack, was a mighty valuable target as one of the few fast fleet oilers in PacFleet. A lucky, random hit on her here could have compromised the American response to Operation MO, to present another example.

So yeah, the hypothetical about attacking the tank-farms seems interesting, but other infrastructure or targets as well presented bottlenecks that might have hamstrung the Americans for a while.

 

[Thumpalumpacus]

Historically, air attacks intending to destroy fuel tank farms didn't produce the predicted easy results. Individual tanks, while some offered quite large targets, proved hard to hit and set alight. The fuel stocks didn't just spontaneously combust. Examples are the Kido Butai's raid on Trincomalee, Sri Lanka in April, 1942, where only one of 101 12,000 ton fuel tanks was destroyed, and that was by what may have been a suicide attack when one aircraft crashed into Tank #91. There's also the allied "Oil Campaign" of which Operation Tidal Wave (Ploiești oilfields) was a part of. There are many reasons why the anti-oil campaign only achieved success after a multi-year series of prolonged and very costly missions (for the attackers), but oil wasn't ever an easy target.

For the ETO oil campaign, it was about refineries rather than storage, as with the hypothetical here, and again there's a mismatch between ammo and target. Your comparison to Op C is more useful, I think, in underlining the difficulties of attacking storage units.

 

[GrauGeist]

The Japanese had the bombs needed to destroy the storage tanks.

They don't need to be a glorious fireball to be taken out, the tank structure only needs to be compromised and the weight of the contents will do the rest.

Pretty sure the Japanese Navy used similar fuel for their ships, so would be very well aware of it's composition.

 

[EwenS]

No argument here. The KdB carriers already had torpedoes for shallow waters. Hitting the doors for the drydocks would have added thousands of miles (round-trip) for any potential battle-damaged ships as they would have had to go to Bremerton or San Diego. And as noted above, the presence of repair ships in PH also meant that the base itself was able to reconstitute quicker, perhaps. I hadn't given much thought to cranes, but that's a good point as well. they're needed to lift and remove armor-plate, turrets, etc, and without them -- especially with drydocks that must themselves be repaired -- it further turns PH less effective and would slow down things like repairing Yorktown for Midway and so on.

Lots of knock-on effects from your point here.

Neosho, near California on the morning of the attack, was a mighty valuable target as one of the few fast fleet oilers in PacFleet. A lucky, random hit on her here could have compromised the American response to Operation MO, to present another example.

So yeah, the hypothetical about attacking the tank-farms seems interesting, but other infrastructure or targets as well presented bottlenecks that might have hamstrung the Americans for a while.

I think the idea of putting the docks out of action with bombs and torpedoes hugely underestimates the problem.

In Dec 1941 PH had two operational dry docks, with another two under construction (a small destroyer sized dock completed in 1942 and a huge one in 1943. Putting dry docks out of action for any length of time isn't easy.

The dock doors were large hollow floating steel caissons, which were towed out of the way to open the dock entrance. They were fairly deep and strongly constructed to withstand the pressure of the water they were required to hold back. Think about how a Battleship TDS would operate to absorb the explosion of a torpedo warhead. Relatively easy to repair if torpedoed or to have new ones built with the Dockyard facilities available.

Look at what it took to destroy the similarly constructed dock gate at St Nazaire in 1942 (a target about 160' wide). Rammed by the 1,200 ton destroyer HMS Campbeltown travelling at 19 knots, the gate held until the 4 ton Amatol charge exploded. Commandos were needed to ensure the destruction of the dock machinery.

DD No 1 contained Pennsylvania, Cassin & Downes. The dock gate itself presented a target about 130' wide, a lot less than the c600' of one of the old Battleships targeted historically. On top of that there would have been no clear run in to it as Helena and Oglala were double berthed further along the quayside, as was the submarine Cachalot. Pennsylvania vacated the DD on 12 Dec.

DD No 2 was empty but would represent a target only c150' wide. On top of that it had provision for an intermediate caisson to divide it in half, which would have allowed at least partial use.

If you really want to disable a dry dock then the pump houses represent a better target. They control the inflow and outflow of water. Problem is they represent an even smaller target for a bomber, and often much of the machinery is buried under concrete in the dock walls themselves. Hence the Commandos at St Nazaire.

There was also at least one floating dry dock present, itself seemingly well sheltered from torpedo attack. YFD-2 contained the destroyer Shaw on 7 Dec 1941. Shaw was bombed and had her forward magazine exploded, damaging the dock itself. However, after being patched up, it was pumped out again on 9 Jan 1942 and was back in service again by May.

 

[EwenS]

Here is a video from the recent past showing the process of docking / undocking a sub in DD#1 at PH with the caisson being moved aside

View: https://www.youtube.com/watch?v=xBueqiOw0zA

And a photo of the DD at PH in July 1942 by which time No.3 was operational. NUmbered from right to left with the floating dock furtherest to the left.

 

[DrumBob]

If the Japanese had been smart, they would have called the whole thing off and never attacked us in the first place. We all know what the outcome was in 1945.

 

[GreenKnight121]

I think CinCPac would have had to pivot to carriers anyway. There weren't enough escorts for both the carriers and the battleships unless you grouped them together and robbed the carriers of their speed asset. Further, iirc USN only had eight fleet oilers (i.e. capable of keeping up with fleet at the latter's cruise speed), so fueling those gashogs is going to be a challenge.

When Nimitz did have the opportunity to use them in battle, at Midway in Jun 42, he instead kept TF 1 on the West Coast.

The New Mexico class BBs (which were the most updated of the old battleships still in active service in mid-1942) were also left behind for the Guadalcanal landings... only the new fast battleships, with their modern heavy & light AA suites, were there... and only as carrier protection, not as fire support/protection for the landing force.

 

[Thumpalumpacus]

... and only as carrier protection, not as fire support/protection for the landing force.

... until Scott's cruisers got shot to Hell and gone, forcing Halsey to deploy Washington and South Dakota into Ironbottom Sound.

 

[Peter Gunn]

... until Scott's cruisers got shot to Hell and gone, forcing Halsey to deploy Washington and South Dakota into Ironbottom Sound.

In all fairness, Scott was riding in Atlanta and Callaghan was put in charge almost at the last moment.

Don't get me started on the idiocy of that change of command move.

Had Scott been commanding, I have no doubt the November 12 knife fight would have not only been totally different, I think Scott would have handed Abe his ass.

 

[Peter Gunn]

The New Mexico class BBs (which were the most updated of the old battleships still in active service in mid-1942) were also left behind for the Guadalcanal landings... only the new fast battleships, with their modern heavy & light AA suites, were there... and only as carrier protection, not as fire support/protection for the landing force.

And to add to that, if I'm not mistaken, the old standards were fuel hogs, couple that with the shortage of both fuel and fleet tankers and it's no surprise the old BB's were kept at home, so to speak.

 

[Thumpalumpacus]

In all fairness, Scott was riding in Atlanta and Callaghan was put in charge almost at the last moment.

Oh, I wasn't criticizing Admiral Scott at all.

Callaghan certainly screwed the pooch in that battle with his delayed torpedo launch and early salvos. Even without those errors, we were up against two battlecruisers and numerous Long Lance-armed escorts. So the American cruisers were going to get shot up no matter what, and Halsey still would have been forced to put BBs in close waters, in my opinion.

Don't get me started on the idiocy of that change of command move.

Had Scott been commanding, I have no doubt the November 12 knife fight would have not only been totally different, I think Scott would have handed Abe his ass.

Agreed. When the USN lost Scott, we lost a great officer who had both brains and courage.

 

[GrauGeist]

What I found ironic, is that history's last great battleship versus battleship brawl was conducted by not only older U.S. battlewagons, but by five Pearl Harbor ghosts (out of six present) at Surigao.

 

[Thumpalumpacus]

What I found ironic, is that history's last great battleship versus battleship brawl was conducted by not only older U.S. battlewagons, but by five Pearl Harbor ghosts (out of six present) at Surigao.

The old ladies were not going to go gently into that good night.

 

[Peter Gunn]

Oh, I wasn't criticizing Admiral Scott at all.

Callaghan certainly screwed the pooch in that battle with his delayed torpedo launch and early salvos. Even without those errors, we were up against two battlecruisers and numerous Long Lance-armed escorts. So the American cruisers were going to get shot up no matter what, and Halsey still would have been forced to put BBs in close waters, in my opinion.



Agreed. When the USN lost Scott, we lost a great officer who had both brains and courage.

Agreed, I didn't think you were critical of Norman Scott.

My "What if" for November 12 is what if Scott had retained command and was riding in Helena, which, as memory serves had excellent radar as well as those 15 six inchers. However I doubt he would have chosen her as he was more familiar with Atlanta and her personnel and may have chosen her. However (again), there was a certain thought that the "big" cruisers were supposed to be flagships so he may well have ridden in San Francisco like Callaghan did.

Again, we'll never know for sure but I don't see him closing in to near collision distance before opening fire, hell, Hoover on Helena was begging to unleash the 15 gun firestorm when the IJN was still 20,000+ yards out.

I digress, back to December 7 and the USN not being at Pearl Harbor.

 

[Thumpalumpacus]

Agreed, I didn't think you were critical of Norman Scott.

My "What if" for November 12 is what if Scott had retained command and was riding in Helena, which, as memory serves had excellent radar as well as those 15 six inchers. However I doubt he would have chosen her as he was more familiar with Atlanta and her personnel and may have chosen her. However (again), there was a certain thought that the "big" cruisers were supposed to be flagships so he may well have ridden in San Francisco like Callaghan did.

Again, we'll never know for sure but I don't see him closing in to near collision distance before opening fire, hell, Hoover on Helena was begging to unleash the 15 gun firestorm when the IJN was still 20,000+ yards out.

I digress, back to December 7 and the USN not being at Pearl Harbor.

A last note on my opinion -- I think Adm Scott would have paid much more attention to his radar, and that may have swung him to favor hoisting aboard Helena after all.

 

[SaparotRob]

I would guess that after his previous battle he probably would've switched ships. He was no dummy.
Good call, Thump.