Operation C 1942

[Carl Schwamberger]

Has anyone got aviation fuel requirements for Nagumo's 500 odd aircraft deployed on his carriers?

In 1944 an ersatz type aviation fuel,dubbed Marianas fuel was introduced.

For some reason the number 900,000 gallons for a carrier with 60 aircraft pops to the surface here. Cant recall if that is the ships storage capacity or some sort of planning base number. The A6M2 Zero topped off at 182 gallons. The dive and torpedo bombers were a lot more.

[Mostlyharmless]

Has anyone got aviation fuel requirements for Nagumo's 500 odd aircraft deployed on his carriers?

In 1944 an ersatz type aviation fuel,dubbed Marianas fuel was introduced.

For some reason the number 900,000 gallons for a carrier with 60 aircraft pops to the surface here. Cant recall if that is the ships storage capacity or some sort of planning base number. The A6M2 Zero topped off at 182 gallons. The dive and torpedo bombers were a lot more.

According to "Shattered Sword", Akagi carried 225,000 gallons of Avgas while Hiryu and Soryu carried 150,000 gallons each. Kaga is given as 600 tons. Shokaku is given as 496 tons in a translation of Kojinsha "Warships of the Imperial Japanese Navy, Volume 6" at http://www.combinedfleet.com/kojinshavolume6.pdf

ps. I am not sure of the density of avgas but assuming about 0.80 - 0.85, 496 tons is roughly 150,000 - 165,000 US gallons.

[Peter H]

Thanks gents.

Peattie relates in Sunburst:The Rise of Japanese Naval Air Power,1909-1941,p 133, that aircraft carrier were fuel guzzlers as it was:

..Carriers steamed at high speeds to provide the wind-over-deck needed to to get aircraft aloft,and in the process they consumed huge amounts of oil..

Hence sengi,"combat skills"training,was limited even prewar:

The First Carrier Division,long the core of the navy's carrier forces,always exceeded its fuel allotment in training and was thus resented by other fleet elements.For this reason,aircraft were generally sent ashore for general flight training and for both bombing and torpedo practice...

[Carl Schwamberger]

ps. I am not sure of the density of avgas but assuming about 0.80 - 0.85, 496 tons is roughly 150,000 - 165,000 US gallons.

I know the gallons per weight vary widely according to temperature. Pilots are susposed to think of fuel reserve in terms of weight not volume. The warmer the fuel the less dense hence the less energy per gallon or liter of volume. The energy of operating range of a fuel tank at 80 degress Fahrenheit is significantly different from a fuel tank with a temperature of 10 degrees Fahrenheit. Dont recall the formula tho. Probablly a aviation website that has it.

[Carl Schwamberger]

Thanks gents.

Peattie relates in Sunburst:The Rise of Japanese Naval Air Power,1909-1941,p 133, that aircraft carrier were fuel guzzlers as it was:

..Carriers steamed at high speeds to provide the wind-over-deck needed to to get aircraft aloft,and in the process they consumed huge amounts of oil..

Hence sengi,"combat skills"training,was limited even prewar:

The First Carrier Division,long the core of the navy's carrier forces,always exceeded its fuel allotment in training and was thus resented by other fleet elements.For this reason,aircraft were generally sent ashore for general flight training and for both bombing and torpedo practice...

This maybe one of several reasons why the naval pilots and air crew were extremly skilled compared to USN aircrew of December 1941, but the deck operations were less effcient. The IJN carrier officers had not yet accumulated the critical mass of information needed to take things to the next level of effciency. The aircrew from combat operations in China and land based training operations could accumulate the knowledge.

[glenn239]

Japanese oil statistics -

Date…Import…..Import…....Home…....Total…..Imported…...NEI
……….Crude…...Refined...Production...Stock….from NEI….Production
42…….1.09……....0.32……....0.23……....5.1………1.4…....…….3.46
43…….1.31……....0.62……....0.24……...3.38…….1.93………....6.62
44…….0.22……....0.44……....0.21….…..1.84…….0.66……....…4.92
45………0……....….…0....……..0.11…..….0.66………0…….....…..0.87

(Total stock = in Japan, imported from NEI means imported to Japan)

(Oxford companion to WW2, pg 1061 using 1 ton = 7.5 barrels)

The difference between the NEI production and imports from the NEI (11.87 million tons) represents oil that was shipped directly from the NEI to the front. So, in 1942, about 2.06 million tons of NEI production was available and not shipped to Japan.

Theoretical calculations based upon "cruising" or "standard" speeds are basically meaningless. They are the equivalent of theoretical operational range/radius for planes...

“Back of the envelope” means a rough ballpark that establishes a general parameter. Such twiddlings can be misleading or inaccurate in specific application, but they are rarely “meaningless”. That same fleet of 10 battleships, 6 carriers, 20 cruisers and 30 destroyers could steam about 12.6 days at 24kt using 305,000 tons of fuel

Other than a 'optimal crusing consumption' does anyone have any numbers for actual consuption?

14kt was roughly 15% of full power, and 24kt is roughly 50% of maximum. If the carrier spends 12 hours on average at 14kt (15%), 6 hours at 18kt (28%) and 6 hours at 24kt (50%), then its fuel consumption would be (12*12)+(6*28/15*12)+(6*50/15*12) = 518 tons. (In comparison, the ship burns 288 tons if cruising at 14kt for 24 hours). If you want to estimate the fuel usage of a raid force, you have to break up the TF’s speed into daily increments (say, 6 periods of 4 hours each), calculate the burn for each increment, then add it all up.

[Carl Schwamberger]

Japanese oil statistics -

Date…Import…..Import…....Home…....Total…..Imported…...NEI
……….Crude…...Refined...Production...Stock….from NEI….Production
42…….1.09……....0.32……....0.23……....5.1………1.4…....…….3.46
43…….1.31……....0.62……....0.24……...3.38…….1.93………....6.62
44…….0.22……....0.44……....0.21….…..1.84…….0.66……....…4.92
45………0……....….…0....……..0.11…..….0.66………0…….....…..0.87

(Total stock = in Japan, imported from NEI means imported to Japan)

(Oxford companion to WW2, pg 1061 using 1 ton = 7.5 barrels)

Those number are close enough to Ellis for our purposes. I have no idea who this "Kirby" is who Ellis cites as his source for this.

The difference between the NEI production and imports from the NEI (11.87 million tons) represents oil that was shipped directly from the NEI to the front. So, in 1942, about 2.06 million tons of NEI production was available and not shipped to Japan.

2.06 million tons or 15+ million barrels does not sound like nearly enough. I vaguely recall that is a quarter of what the USN used in the Pacific in the same period. Unfortunatly neither Ellis or Costello refer to USN or Allied fuel consuption for naval operations.

Theoretical calculations based upon "cruising" or "standard" speeds are basically meaningless. They are the equivalent of theoretical operational range/radius for planes...

14kt was roughly 15% of full power, and 24kt is roughly 50% of maximum. If the carrier spends 12 hours on average at 14kt (15%), 6 hours at 18kt (28%) and 6 hours at 24kt (50%), then its fuel consumption would be (12*12)+(6*28/15*12)+(6*50/15*12) = 518 tons. (In comparison, the ship burns 288 tons if cruising at 14kt for 24 hours). If you want to estimate the fuel usage of a raid force, you have to break up the TF’s speed into daily increments (say, 6 periods of 4 hours each), calculate the burn for each increment, then add it all up.

Ow! Arithmitic, too hard

[Mostlyharmless]

Firstly a mea culpa, the density of avgas at 15 deg. C is about 0.72 kg/l. Thus Shokaku's 496 tons is about 182,000 US gallons and Kaga's 600 tons is about 220,000 US gallons.

Secondly, as well as discussing Japanese avgas, do we know how much avgas was stored in India? How soon will all air operations of British aircraft from India and Ceylon (and the AVG in China) end if tankers stop arriving in India? If aircraft from India are grounded, Japanese ships in the Indian Ocean south of India are unlikely to be found by any hostile forces (unless submarines can use broken Japanese codes). This reduces the escorts needed for tankers and also fuel consumption.

[john whitman]

Who is source Kirby? Most likely Stanley Woodburn Kirby, The War Against Japan. Volume I. The Loss of Singapore (London: Her Majesty’s Stationary Office, 1957).

John

[Carl Schwamberger]

Who is source Kirby? Most likely Stanley Woodburn Kirby, The War Against Japan. Volume I. The Loss of Singapore (London: Her Majesty’s Stationary Office, 1957).

John

Sounds reliable. Is he? One of course hopes Ellis is passing this info along with minimum distortion, and had checked it.

[glenn239]

2.06 million tons or 15+ million barrels does not sound like nearly enough.

2 million tons is enough fuel to keep a fleet of 10 battleships, 6 carriers, 20 cruisers and 30 destroyers at sea for 151 days, assuming that on each day the ships will spend 12 hours at 14kt, 6 hours at 18kt and 6 hours at 24kt.

[Carl Schwamberger]

This naval oil thing is getting interesting. If we keep this up for a couple months meaningless disconneccted numbers may actual gel into something usefull... imagine that.

2 million tons is enough fuel to keep a fleet of 10 battleships, 6 carriers, 20 cruisers and 30 destroyers at sea for 151 days, assuming that on each day the ships will spend 12 hours at 14kt, 6 hours at 18kt and 6 hours at 24kt.

Ok, 151 days = 5 months. Roughly the lenght of the Guadacannal campaign. Of course the actual days at sea and underway speeds varied a lot. The largest fuel hogs, the Yamamoto & Musahi sat in Truk & ran a hotel serivice for senior admirals, the others went hither & yon occasionaly from August to December, but less than ten actually went on combat sorties into the Solomons in those months. Aircraft carriers may have accumulated more sorties or days at sea than the BB, but it was probablly not close to 6 for 151 days even when administrative moments, traning ops, and other reasons are counted. Conversely the IJN did utilize its crusiers and destroyers to the maximum in the Solomons/New Guinea campaigns. Reading my way through Franks "Guadacannal' leaves me with the impression the destroyer days at sea ammounted to more than 30 per day when escourts in & out of the area are counted. And, in the combat operations the high speed portion of the day may have been more than six hours per. The loss when a fair number of the ships went to negative bouyancy may not have been trivial.

The thing is, this...

Japanese oil statistics -

Date…Import…..Import…....Home…....Total…..Imported…...NEI
……….Crude…...Refined...Production...Stock….from NEI….Production
42…….1.09……....0.32……....0.23……....5.1………1.4…....…….3.46
43…….1.31……....0.62……....0.24……...3.38…….1.93………....6.62
44…….0.22……....0.44……....0.21….…..1.84…….0.66……....…4.92
45………0……....….…0....……..0.11…..….0.66………0…….....…..0.87

(Total stock = in Japan, imported from NEI means imported to Japan)

(Oxford companion to WW2, pg 1061 using 1 ton = 7.5 barrels)

The difference between the NEI production and imports from the NEI (11.87 million tons) represents oil that was shipped directly from the NEI to the front. So, in 1942, about 2.06 million tons of NEI production was available and not shipped to Japan.

... the 2.06 million tons oil is the ammount for a year not 151 days, and it also is needed for other purposes outside Japan. The cargo fleet was busy doing its thing. I have no clue what the six or seven million tons of merchant ships would have burned off as fuel. Presumably a lot less per ship than the warships, and at least some were coal burners. Also one can guess that cargo ships departing Japan refueled there & were drawing from the considerable surpluss there in 1942. Industrial use in Indonesia, Phillpines, Indochina, Burma, and China must have drawn from some of this 2,06 mil. tons. Then there were whatever the Japanese Army requirements might have been for its campaigns. Whatever these other uses consumption was, two million tons does not look like enough for a year or even the last five months of 1942. Maybe there was some other oil not accounted for here?

Damm this logistics stuff is cool

[cstunts]

Hello,

Yes, really cool...like the math geniuses who gave us the banking mess we're in today....

But, back to reality: You will be hard pressed to find ANY Japanese naval veteran who will tell you they had more than enough oil in this time frame, let alone later. Far from it. But, you can find many who will state that fuel concerns, regardless of their conquests in the Nam'po, were constant & chronic, and did indeed shape their thinking and actions. Not that that matters here, since these AH musings--numbers and all--operate entirely within the realm of fantasy...

[glenn239]

Ok, 151 days = 5 months. Roughly the length of the Guadacannal campaign.

The 2 million tons of oil in the NEI in 1942 represented at total equal to 33% of Japan’s entire pre-war strategic oil reserve, and enough to fill 200 tankers (ie the entire Japanese tanker fleet about 3-4 times over). It is not a trivial amount.

Yes, really cool...like the math geniuses who gave us the banking mess we're in today....

Every drop of oil used by the Japanese navy in the Solomons campaign had to be hauled there from the Netherlands East Indies by tanker, a round trip of perhaps 9,000 NM, assuming a direct haul. That is a very, very long supply chain. If the IJN instead is operating from its oil sources, then its fleet of tankers do not have to make a 9,000NM mile journey to deliver their load. Are we clear on the operational significance of that point, or does it require further explanation?

[CharlesRollinsWare]

Peter H wrote:

Has anyone got aviation fuel requirements for Nagumo's 500 odd aircraft deployed on his carriers?

Just a quick comment. At no time did Nagumo's Kido Butai ever carry near 500 aircraft. At its maximum (for the Hawaiian Operation) the six carriers having embarked numerous spares, carried 399:

Akagi:.....21 VF, 18 VB, 27 VT = 66
Kaga:......21 VF, 27 VB, 27 VT = 75
Soryu:.....21 VF, 18 VB, 18 VT = 57
Hiryu:......21 VF, 18 VB, 18 VT = 57
Shokaku:..18 VF, 27 VB, 27 VT = 72
Zuikaku:...18 VF, 27 VB, 27 VT = 72

Thereafter, having lost a a considerable number in action, the numbers steadily fell for all subsequent operations. After returning to home base, only Kaga and the two Shokakus ever embarked more than 18 of any one type and the later never reached full units of 27 again until after Midway. For the C Operation, the numbers were 273:

Akagi:.....18 VF, 18 VB, 18 VT = 54
Soryu:.....18 VF, 18 VB, 18 VT = 54
Hiryu:......18 VF, 18 VB, 18 VT = 54
Shokaku:..18 VF, 19 VB, 19 VT = 56
Zuikaku:...18 VF, 19 VB, 18 VT = 55

Ryujo had 12 A5M4 Type 96 fighters and 15 B5N Type 97 attack planes (of the later's three Chutai, only one was was equipped with the B5N2, the two other having the earlier underpowered B5N1 model).

Hope this is of interest.

Mark E. Horan