What if japan hit the fuel stores at pearl harbour?

stripping out 50 or so MORE US tankers to store replacement fuel within PH could only advance that schedule GREATLY. Which quickly results in catastrophic U-boat Atlantic kill numbers against Allied Lend/Lease convoys bound for Britian, Russia and the Mediterranean area ... Malta falls ? ... the Suez Canal falls ? ... Britain falls ? Russia drops out of the war ?

Its a staggering list of potential failures.

No, all I can see would be a USN Pacific Fleet retirement back to the US West Coast ...
The odds of destroying enough tanks you need to strip 50 tankers out to supplement Pearl storage are incredibly low, you might as well start talking about the odds and effects of a every tank in Pearl simultaneously exploding, setting off every volcano in the Hawai'ian islands, and then setting off a sympathetic eruption of the Yellowstone megavolcano.
 
Actually, the majority of the PH fuel storage tanks were built as cheaply as possible for the 1923/4 era by oil companies involved in the "Great Teapot Dome Scandal" so they had NO such expensive and hard to maintain floating inner roofs ... while most modern fuel storage tanks certainly do ... thought they still burn out on occasion too ... Zimm claims that they had floating roofs but his widely read PH Myths book also claims (assumes) that those PH fuel storage tanks had steel wall thicknesses of between 1.5" and 3" when a bit of www research would have provided him with the only 1/2" mild rolled steel plate truth ... as a result of his faulty assumptions wrt the PH fuel storage tanks, his computer modelling included storage tanks many times more difficult to puncture / ignite than would have been the actual case at Pearl Harbor.



Possibly but my understanding of Japanese divebombing tactics of the time was that the 2 "wingmen" were supposed to watch the fall of their shotaI leaders's bomb before adjusting their own aim ... with the PH fuel storage tanks clustered so closely together, I think it reasonable that those "wingmen" could aim at 2 adjacent tanks after their leader's bomb actually hit a storage tank ...

I suspect that the more difficult problem would have been the smoke screens produced by burning fuel storage tanks obscuring the aim of follow on IJN Val divebombers ... a problem solved easily enough by starting with bombing downwind fuel storage tanks ... with the huge smoke pyres generated by the IJN's first wave air attacks on the USN warships within PH providing hard to miss seeing wind direction indicators ...

in any case, the 18 day Pembroke Docks fuel oil fire certainly points out the ability of adjacent oil storage tank fires to radiantly heat up other fuel storage tanks close to them, to the point of those venting highly combustible fumes into an area full of active fires ...
I believe the Pembroke dock tanks were not separated by the distances at PH. and did not have the berms around them capable of holding each tank's full capacity.
Here is a link to an Official USN document about the facilities.http://lcweb2.loc.gov/master/pnp/habshaer/hi/hi0600/hi0642/data/hi0642data.pdf
 
The oilers rendezvouzed with the strike force on December 9th and performed refuelling tasks at that time. KB then hit bad weather and refueling became impossible for several days.
As I said the IJN was prepared to tow or scuttle, not planned to do that. tow or scuttle was a last chance resort.
 

rascal1225

Banned
Here is a link to an Official USN document about the facilities.http://lcweb2.loc.gov/master/pnp/habshaer/hi/hi0600/hi0642/data/hi0642data.pdf

Many thanks for that, though I believe that I posted that very same link myself earlier today in my posting #63 here - sigh.
 
Found it by asking some friends of mine, I know the book but it is in my storage but I was able to find an archive copy online to look at.

Alan Zimm's "Attack on Pearl Harbor"?

On pages 315-321 he deals with a potential attack on the fuel depots. 54 tanks in two complexes, each tank surrounded by its own earth berm and with its own fire suppression system. Plus separate avgas storage on Ford Island. Total 563k tons. On top of that underground storage at Red Hill was being developed and although officially opened in Sept 1942, tour guides state that in Dec 1941, 3 tanks were complete with 1 filled.

He states the tanks were of the type that had a steel conical top to keep the water off of them and a floating steel top so there was no air gap to have fumes accumulate in the tank, especially the in the AVGAS tanks. Individual tanks with steel sides that tapered from 0.75-1.5 inches thick. So MG & cannon fire from Japanese weapons won't do the job.

And the difficulty of producing enough radiant heat from one tank set alight triggering destruction of another. He ran computer simulations (1,000+ runs) estimated hits on only 22-35 of the tanks from the 280x250kg bombs the Japanese could have deployed. He estimates 1 hour plus for a fire in one tank to raise the radiant temp enough to trigger a fire in an adjoining one. He also stated that there was a system of water pipes and spray system to cool the tanks in normal use as a safety measure in case one caught on fire in an accident in addition to having its own dedicated fire department.

He also states there was transfer pumps available to pump the fuel out of the berms and into the fuel lines or directly to the adjacent tanks.

He also assesses how many tankers, continuously employed, would be required to replenish stocks. 1 month - 13-20. 2 months- 7-10. 3 months-5-7. After that it is only steel for the tanks to be shipped estimated at around 5.,000 tons that was more than available on the west coast at the time. Plenty of fabrication equipment available in the shipyard.

He also states that 3 of the chambers at Red Hill were open with one actually being filled but it was considered a secret at the time which was the basis of Nimitz's statements about the fuel tank farm.
 
If Neosho was full of avgas fumes, I would think even the sparks caused by being hit by an AP bomb would set everything off.
It depends, if the fumes are too ri ch, you many not get the right fuel vapor oxygen mix. Those fumes will be confined to each tank on the Nesho. There are many variables based on fuel air mix, air temp and explosion. A powerful enough explosion can snuff itself out.
 
OK folks; Here are the Japanese Oilers assigned to 1st Air Fleet(AKA Kido Butai)
Research IJN Oilers of 1st Air Fleet

Tonnage Speed Cargo

Nippon Maru 9.9k 18-20kts 14590m3

Toho Maru 9.9k “ “

Kyokuto Maru 10k “ 16100m3

Toei Maru 10k “ “

Kokuyo Maru 10k “ “

Ken’yo Maru 10k “ “

Shinkoku Maru10k “ 16100m3

This link will take you to a specific Oiler, but scroll down the page you get all the IJN Oilers and Fleet assignments. https://en.wikipedia.org/wiki/Japanese_fleet_oiler_Kazahaya
Looking up these ships on Combined Fleet, they are faster than this list says. All were in the 18.5-19.5 knot range.
Etc. These were all civilian tankers requisitioned by the IJN just before the war.

The Actual IJN Fleet Oilers at the start of the war were all slower at 14 knots.

 
Looking up these ships on Combined Fleet, they are faster than this list says. All were in the 18.5-19.5 knot range.
This is the list I'd compiled of available tankers and oilers - type, oil carried, name, displacement, assignment.

oiler
12500​
Kiroshio
10519​
Oiler
12687​
Kyokuto
10051​
1st air fleet
Oiler
12031​
Toei
10022​
1st air fleet
Oiler
12031​
Kokuyo
10027​
1st air fleet
Oiler. Refuelled Akagi with 435 and 607 tons
12031​
Kenyo
10024​
1st air fleet
Oiler
13324​
Nippon
10009​
1st air fleet
Oiler
12687​
Toho
9997​
1st air fleet
Oiler
12728​
Shinkoko
10020​
1st air fleet
did not participate in mission due to wrong hoses. Oiler from 7 Jan. 42
15007​
Akebono
10182​
1st air fleet
Oiler
12687​
Toa
10051​
4th Fleet
converted to oiler. Did port refueling
12960​
Hoyo
8691​
4th Fleet
tanker, conversion completed Dec 20th
12960​
Kaijo no2
8632​
4th Fleet
oiler
8000​
Shiretoko
15450​
4th fleet
oiler
8000​
Iro
15540​
4th fleet
oiler
8000​
Naruto
15540​
4th fleet and southern drive
German. Tanker 1942
6341.25​
Teikon
5073​
German
tanker
11905​
Fujisan
9527​
Hawaii, sub support
tanker
12000​
San Ramon
7309​
home
tanker
12000​
San Pedro
7268​
Home
tanker
12000​
San Luis
7268​
Home
tanker
9139​
Ogura 2
7311​
Home
tanker
9188​
Ogura 3
7350​
home
tanker
11506​
Nissho
10526​
home
tanker in nov 41
21000​
Kyokuyo
17549​
home
tanker as of nov 41
21001​
Nisshin
16764​
home
tanker
397.5​
Moji
318​
home
tanker
758.75​
Kyoei
607​
home
tanker
1486.25​
Kyoei 2
1189​
home
tanker
1486.25​
Kyoei 3
1189​
home
tanker
1083.75​
Kinrei
867​
home
tanker
598​
Juko
478​
home
tanker
9550​
Kiyo
7251​
home
tanker
10843​
Eiyo
8673​
home
oiler
8000​
Sata
15540​
home
oiler
8000​
Ondo
15540​
home
tanker
11839​
Tonan
9866​
Home
Oiler
12031​
Itsukushima
10018​
Home Islands
tanker
12687​
Takekawa
10009​
Home Islands
oiler
15007​
Akatsuki
10216​
Home Islands
oiler
8000​
Tsurumi
15540​
home then java
tanker
9741​
manju
6515​
home, 4th fleet
Oiler
12312​
Teiyo
9849​
home, then Java
tanker
11506​
Owatasan
9204​
IJA
tanker
9741​
Tachibana
6515​
IJA
tanker
11506​
Omurosan
9204​
IJA
tanker
1407.5​
Kaisoku
1126​
IJA
tanker
9000​
Ogura 1
7270​
IJA
tanker
11476.25​
Rikko
9181​
IJA
tanker
7001​
Hokki
5601​
ija
tanker
1362.5​
Kyodo
1090​
ija
oiler
8000​
Shiriya
15540​
midway then home. 8kt
Double counted tanker/seaplane tender
10000​
Kamoi
17000​
seaplane tender
Oiler
12031​
Genyo
10018​
Southern Drive
Oiler
12031​
Nichiei
10018​
Southern Drive
oiler
12000​
San Clemente
7309​
Southern Drive
tanker
12000​
San Diego
7268​
Southern Drive
oiler as of 6 December
6540​
Toen
5125​
Southern Drive
tanker, supply oil dec 41
23114​
tonan 2
19262​
Southern Drive
oiler
1070​
Hishi 2
856​
Southern Drive
tanker
1486.25​
Hishi
856​
southern drive
oiler
8000​
Notoro
14050​
Southern drive
oiler
8000​
Erimo
15540​
Southern drive
oiler
8000​
Hayatomo
15540​
Southern drive
tanker
10300​
Shoyo
7499​
Southern Drive, 4th fleet
tanker as of March 42
23114​
tonan 3
19209​
tranport, southern drive
tanker, fresh water and oil
1486.25​
Koryu
974​
Kuroshiois Kiroshio
 

rascal1225

Banned
Looking up these ships on Combined Fleet, they are faster than this list says. All were in the 18.5-19.5 knot range.
Etc. These were all civilian tankers requisitioned by the IJN just before the war.

The Actual IJN Fleet Oilers at the start of the war were all slower at 14 knots.


Just a quick terminology clarification request if I might ?

I have long understood "fleet oiler" to mean a modified tanker capable of carrying and pumping via underway refueling, a wide variety of fuels to include naval fuel oil, diesel, avgas and possibly gasoline etc.

Since the Kido Butai first trained itself in underway refueling techniques while on its way to Hawaiian waters, how can the Japanese Combined Fleet also have had some 14 slow fleet oilers prior to that secret mission ?

Or are my definitions just wrong ?
 
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Just a quick terminology clarification quest if I might ?

I have long understood "fleet oiler" to mean a modified tanker capable of carrying and pumping via underway refueling, a wide variety of fuels to include naval fuel oil, diesel, avgas and possibly gasoline etc.

Since the Kido Butai first trained itself in underway refueling techniques while on its way to Hawaiian waters, how can the Japanese Combined Fleet also have had some 14 slow fleet oilers prior to that secret mission ?

Or are my definitions just wrong ?
My sense is fleet oiler designation is about the origins of the ships, not their function. They were purpose built as navy ships. The ship names do not contain Maru, signifying they are military ships, not merchants. The IJN noticed they had a shortage of tankers, and made that up by requisitioning civilian tankers, and converting civilian merchants to tankers, and building new, but the naval fleet oilers are the only ones on the list that do not have Maru in their names.

I think.
 
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rascal1225

Banned
Some US Government sources in confirmation of my belief that the PH fuel storage tanks had NO floating internal roofs on Dec.7'41.

This one confirms that a floating roof was not installed until 1944

Yes, I realize that these few sources do not confirm that ALL of the 80 odd big PH fuel storage tanks that I previously identified had fixed conical roofs rather than internal floating ones but, its a start ... and https://docslib.org/doc/8911185/us-naval-base-pearl-harbor-fuel-facilities-before-1938 states that all of the PAPTC 1923/4 built fuel storage tanks in the Upper, Middle, Lower, Ford Island and Merry Point tankfarms had low pitched conical roofs, certainly confirming that the majority on Oahu were built that way.

That same source also provides "In the immediate aftermath of the attack, some minor improvements and repairs were made to the tank farms.
An ensign in the Civil Engineer Corps reported that they changed all pipe-line fittings from cast iron to wrought iron, installed portable foam systems, stopped leaks caused by penetration of machine-gun bullets with wooden plugs, and placed a six-inch clay layer throughout the berms in order to prevent oil leakage into the harbor and the resulting fire hazard" ... thus confirming that machine gun bullets COULD indeed penetrate those fuel storage tanks AND that the berms surrounding those same fuel storage tanks were indeed LEAKY on Dec.7'41.
 
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