JApanese logistic weakness and carrier operations

[steverodgers801]

Just had a thought since the Japanese had not developed a means to sustain carrier operations at sea, would that be one reason Yamamoto had relied on his BB's so much. It wasn't until 1944 that the US had fully developed the logistic support that enabled their carrier groups to stay at sea. I wonder if Yamamoto had reasoned that the US carriers would be good for one battle so even if they had hit some Japanese carriers they probably wouldn't be able to stay for a second,this assumes that not all four would be sunk. Look at how effective the Hiryu was alone, imagine if two or three had survived. Once the American carriers would have to withdraw then BB's would be king.

[Kingfish]

Just had a thought since the Japanese had not developed a means to sustain carrier operations at sea, would that be one reason Yamamoto had relied on his BB's so much.

If so then he did a piss poor job of allocating that resource properly. Of the 11 BBs available, 4 went to the Aleutians, 2 more escorted the invasion force, and 3 were following far behind the 1st air fleet. This left only two at the tip of the sword.

[steverodgers801]

Its the other three that would be the main. Remember the US had none at the time so even those few would be more then a match

[glenn239]

Just had a thought since the Japanese had not developed a means to sustain carrier operations at sea, would that be one reason Yamamoto had relied on his BB's so much. It wasn't until 1944 that the US had fully developed the logistic support that enabled their carrier groups to stay at sea.

It was not until 1944 that the USN needed to sustain its carriers at sea, at which point they whipped up a workable system in no time. That suggests it wasn't the date that drove the solution, it was the operational requirement. (ie, had the USN decided it required this capacity in 1935, they'd have done it in 1935).

On the Japanese side, carrier logistics were in four groups - general upkeep, ship fuel and victuals, avgas and munitions, and aircraft.

Aircraft - capacity for some spares, but generally return to port upon depletion of air wing.
General upkeep - major port every 6 months or so.
Ship fuel and victuals - Underway sea replenishment capacity for each existed.
Avgas - underway sea replenishment capacity existed, (same systems as oil transfer)
Aircraft Munitions - never done at sea (AFAIK), but basic capacity existed to do so if doctrine was desired.

[Takao]

Its the other three that would be the main. Remember the US had none at the time so even those few would be more then a match

None what? Battleships?
New Mexico, Idaho, Mississippi, Tennessee , Maryland, Colorado, and Pennsylvania composed Task Force 1 some 1,200 miles west of San Francisco. They were playing backstop to the carriers should the Japanese Fleet head for the West Coast. Still, they were several days steaming(at about 18 knots) from Midway.

[steverodgers801]

I had thought that they were all still on the coast.

[steverodgers801]

Regardless, of why it was still 1944 before the US had the means to sustain carrier operations at sea for a long time. Sure they had fueling, but it was also the other kinds of supply that had to catch up.

[Takao]

I had thought that they were all still on the coast.

Essentially they were, given that Nimitz did not have the fleet train to support both them and the carriers out of Pearl. However, if the battle had gone badly, with some of the carriers lost, the battleships could have been brought up and the fleet train supporting the lost carriers could be used to support the battleships.

Regardless, of why it was still 1944 before the US had the means to sustain carrier operations at sea for a long time. Sure they had fueling, but it was also the other kinds of supply that had to catch up.

Because the US did not need or want to conduct extended carrier operations at sea for a long time. Until late 1943-early 1944, the US had few fleet carriers, and not the numbers needed for conducting extended operations. If the few US carriers had conducted extended operations, there was a fair chance that the Japanese could mass land-based and/or carrier-based aircraft to defeat them. Once the Essex class CVs and Independence Class CVLs began joining the fleet in significant numbers, the US now had the capability for their aircraft carriers to stay in one place, while still being able to retain air superiority against whatever the Japanese could throw at them.

[glenn239]

Regardless, of why it was still 1944 before the US had the means to sustain carrier operations at sea for a long time. Sure they had fueling, but it was also the other kinds of supply that had to catch up.

There was nothing magic about loading a barge with a skid bombs and then hauling the load by crane up onto the deck of a carrier in calm seas. The Germans even on occasion transferred torpedoes onto warship at sea in calm weather. And seaplane carriers such as Tone or Chikuma did it all the time with their seaplanes which weighed over 6,000 lbs, and these were one heck of a lot more delicate than a pallet of bombs. A Diahatsu could carry ten tons and a crane that can lift an E13A1 Jake must be good for 3 tons. So that would be three lifts of three tons each, which would anywhere from 36 x 500lbs bombs to 10 x 1,800lbs torpedoes, per barge run.

[steverodgers801]

The Japanese did not have a fleet of ships dedicated to resupplying a task force, so your point is mute.

[glenn239]

The Japanese did not have a fleet of ships dedicated to resupplying a task force, so your point is moot.

There’s three forms of logistic support in question. Advanced base maintenance, (floating drydocks, etc) of which the IJN had few resources – we can dismiss outside-Japan-capacity for that pretty quick, except for special cases like Singapore. Underway refuelling, (oil and avgas) for which the IJN had plenty of ships already – KB itself had a dedicated capacity of about 50,000 tons, beefed to 80,000 tons on special occassion. The third category was the one that didn’t exist historically, the underway at sea ordinance capacity. You indicate that the IJN didn’t have the “ships” for that. The entire magazine of an aircraft carrier was something like –
300 x 500lbs bomb
100 x 1600lbs bomb
45 x torpedo.
Total weight = 350,000 lbs (175 tons = 20 barge runs)
The shipping requirement might be two ships of 5,000 tons with say, six barges each plus a pair of cranes able to operate them. (In fact, an entire reload of ammunition for all of the KB could obviously be carried on just one supply ship, since 175 tons * 6 = 1,050 tons, about 15% of the weight an average freighter could carry). However, you’d have to figure that KB would want to replenish one division of carriers at a time, so two supply ships with about 6 barges each might be more appropriate. That way one supply ship each services one carrier. But clearly (1) the number of supply ships isn’t exceptional and (2) the logistic consideration is the transfer of the material, not the shipping weight of it. (For example, I think a carrier could have 170 tons of ordinance sitting in its hanger awaiting lift below to the magazine, but I’m not 100% sure of it).

[ChristopherPerrien]

Just had a thought since the Japanese had not developed a means to sustain carrier operations at sea, would that be one reason Yamamoto had relied on his BB's so much. It wasn't until 1944 that the US had fully developed the logistic support that enabled their carrier groups to stay at sea. I wonder if Yamamoto had reasoned that the US carriers would be good for one battle so even if they had hit some Japanese carriers they probably wouldn't be able to stay for a second,this assumes that not all four would be sunk. Look at how effective the Hiryu was alone, imagine if two or three had survived. Once the American carriers would have to withdraw then BB's would be king.

I am a little puzzled by this. The Japanese BB line was not that impressive. 2 new BB's(including later Musashi) 2 older good BB's , 4 BC's and 4 old "Dreadnoughts". Not something to rely on. At Midway, he had 3 BB's and 4 BC'c at best, but divided these into 3 groups(IIRC). US had 7 BB's(all "standards" more or less). He sent the 4 old dreadnought off on Op. AL.

As to "staying power" of US Carriers , the "fleet train" need is beside the point. The example of the USS Yorktown , surviving Coral Sea knocking out 2 Jap. CV's and sinking 1 CVL, then fighting at Midway, assisting in the sinking of 4 CV's , before going down , dwarfs the staying power of the lone Hiryu. And then there is USS Enterprise, which as a warship, was and still does represent the zenith of "staying power" for all time except for maybe the USS Constitution , maybe the HMS Q.E. . Japanese fleet CV's were basically equivalent to US CVL's in staying power IMO. US Yorktown class and their larger bother Essex class had no true equals. On a side note , the Lexington class held up fairly well too, the Lex sunk after 4 hits at Coral Sea, but the Saratoga took so many in her career I lost count, and it took TWO Atom Bombs, to sink her

As has been noted, the early US carrier groups/task forces were so small (1-2 CV's) by doctrine, they needed little support. When US carrier groups grew to 10-20 CV's-CVL's, they had all the support they needed.

There seems to be little of Yamamoto's thought's on this , or I simply do not know of any.
It seems he wore one black shoe and one brown shoe and really never made up his mind of either.

[Rob Stuart]

Regardless, of why it was still 1944 before the US had the means to sustain carrier operations at sea for a long time. Sure they had fueling, but it was also the other kinds of supply that had to catch up.

There was nothing magic about loading a barge with a skid bombs and then hauling the load by crane up onto the deck of a carrier in calm seas. The Germans even on occasion transferred torpedoes onto warship at sea in calm weather. And seaplane carriers such as Tone or Chikuma did it all the time with their seaplanes which weighed over 6,000 lbs, and these were one heck of a lot more delicate than a pallet of bombs. A Diahatsu could carry ten tons and a crane that can lift an E13A1 Jake must be good for 3 tons. So that would be three lifts of three tons each, which would anywhere from 36 x 500lbs bombs to 10 x 1,800lbs torpedoes, per barge run.

Glenn,

What Tone and Chikuma did was not the same at all as transferring ammo between underway ships. Tone and Chikuma launched their aircraft by catapult, and to be recovered the aircraft taxied up to its mother ship and was hoisted aboard. At no point was any floatplane ever swayed over from one moving ship to another using lines strung between them.

[glenn239]

The example of the USS Yorktown , surviving Coral Sea knocking out 2 Jap. CV's and sinking 1 CVL, then fighting at Midway, assisting in the sinking of 4 CV's , before going down , dwarfs the staying power of the lone Hiryu,.

Yorktown stopped at Pearl Harbor for 72 hours of repair and replenishment between Coral Sea and Midway, including drydock time and switching in new air units.

What Tone and Chikuma did was not the same at all as transferring ammo between underway ships. Tone and Chikuma launched their aircraft by catapult, and to be recovered the aircraft taxied up to its mother ship and was hoisted aboard. At no point was any floatplane ever swayed over from one moving ship to another using lines strung between them.

I didn't picture anything like that. The ‘off the shelf’ method I thought the IJN might be able to adapt would be a Diahatsu carrier supply ship with 2 cranes and maybe 6 barges. In good weather, the supply ship lowers the barges into the water and then loads the ordinance into the barge. The barge then moves from the supply ship to beside the carrier, where the carrier’s crane lifts the crate onto the flight deck with the barge alongside, repeating as necessary. The disadvantage to this method is that the carrier would have to remain at low speed (4kt?) for several hours during the operation.

[ChristopherPerrien]

Yorktown stopped at Pearl Harbor for 72 hours of repair and replenishment between Coral Sea and Midway, including drydock time and switching in new air units.

Yes but that is the amazing thing and really high-lights the topic header "Japanese logistic weakness and carrier operations"

The Skokaku was similarly damaged in the same "Sea" and it took the Japanese 6 weeks to fix her. And also they could not manage to form one air-group from the Shokuku/Zuikaku/ and "JAPAN/all the IJN" to sail on the Zuikaku for Midway.

That really showed their weaknesses in this respect; And a serious oversight on Yamamoto's part, not getting those 2 carriers fixed , or at least one for Midway.

Remember all the discussions we had on replacement pilots/aircrew after Pearl Harbor/for the 1st Airfleet/IJN in general. It seems they had hundreds yet they could not fill out one replacement carrier air group, after Coral Sea.