Amphibious invasion of Pearl Harbor - results

[Mynok]

Right...well, the Daihatsu's were 14m boats, so I'm guessing not alot could be stored on deck on an AK. Looking at the 2 AKs in the game's Khota Baru TF, they had a capacity of 2180. 18 barges unloads it all, but I'm guessing more like 6 barges in 3 trips.

[WITPPL]

it looks like it is relatively easy to hit a transport.
but to hit hard a transport with troops still there is not.

I got an idea:

River crossing vs heavy defended and fortified fronts.

Russians done it at least twice with closest to our subject would be a river ODER crossing in 1945.
In a place called Seelowe Hights.

This can answer the reall effect of heavy prepared artillery vs small fast moving targets. If we got the right numbers [:D]

[Mynok]

The Lingayen landings for comparison unloaded 43000+ troops of the 48th division plus some other troops, so I'm suspecting a LOT more ships and barges. 370 barges for one wave to be exact. That's probably more realistically 120 barges in 3 trips, meaning 20 ships with six barges each. And then there's support units and artillery to take into account.

[WITPPL]

CDs "in being" policy

I tell you

Loks to me that a defence of a large target (not just a sector of it) by CDs alone is a myth and that they knew it.

[Mynok]

That they were feared is beyond question. That they should have been....well, that's open to debate.

[WITPPL]

This Oder crossing is a nice example.
Germans had hundreds of heavies well aimed and prepared but loses during an actuall crossing were very low comparing to later fighting.

Ah, You know, i think that its just a matter of calculations. If we can avoid them, we should just to minimini our loses. This approach do not mean that they were considered unpenetrable.

Corregidor anyone?
Singapore landing by Brits? Yes there were one.

ORIGINAL: Mynok


That they were feared is beyond question. That they should have been....well, that's open to debate.

[Mynok]

I really don't see the comparison between river crossings and invasions. The time factor you brought up is the issue. Rivers are narrower than any landing approach....by far.

The real issue is: CD's can target stationary, off-loading transport fine. But they can't deal with landing craft. So how many transports can they engage and kill before they offload? That's the question.

[John Lansford]

The Soviets had overwhelming strength in airpower and artillery in 1945; comparing any river crossing with an amphibious landing is pointless; they aren't anything like each other.

At Tarawa, the Marines found that the first wave of amtracks were unable to bring in the second wave due to damage and loss to the first wave's vehicles.  Fewer and fewer vehicles were available for successive waves, making each one take longer to get to shore.  The same would have happened with any forced assault against a heavily defended beach for the Japanese.

[WITPPL]

i brought it up, because its not only about shooting transports but also LCs.
PLUS

there were no invasions "vs" large quantity of prepared CDs. There were river crossings vs large prepared heavies.

Over. Do not look into abyss for to long....

ORIGINAL: Mynok


I really don't see the comparison between river crossings and invasions. The time factor you brought up is the issue. Rivers are narrower than any landing approach....by far.

The real issue is: CD's can target stationary, off-loading transport fine. But they can't deal with landing craft. So how many transports can they engage and kill before they offload? That's the question.

[Alfred]

Back in post #437 on page 15, I made certain observations regarding tonnage.  It seems to me that perhaps I did not express myself clearly enough.  So here we go again, succinctly this time.

(1)  I see absolutely nothing gamey about how WITPPL conducted his invasion of Pearl Harbor.  He should be applauded for his vision and skill in implementation.  It was not his fault that the CD defenses generated an outcome which most posters on this thread consider to be unsatisfactory.

(2)  Many posters have made interesting suggestions to address the perceived deficiencies.  To me they all suffer from the same problems - (a) they risk creating far worse unintended outcomes down the track, (b) probably involve tricky coding issues (as evidenced by a recent developer post that no changes to CD routines are being considered), and (c) open up new arbitrary limits which will be exploited by players and in turn will lead to cries of gameyness.

Personally I am not convinced that a problem exists, certainly not to the extent that coding changes are required.  However, having said that, if there is a consensus view that some coding changes are appropriate, I vote, on the basis that it is probably less taxing on the developers and less likely to be gamey, to limit the total aggregate tonnage in a task force/s which may unload on an enemy hex each day, to that which exists pierside at a level 10 port.  Whether you are unloading at a level 0 or level 9 port would be immaterial, the aggregate would be a maximum of 176,000 tons whether it is concentrated in one or twelve separate task forces, whether they be amphibious/landing craft/surface combat/bombardment/mine sweeper etc.

Alfred

[TheElf]

A couple facts....points.

1) Fact: Players rarely play like losing Hawaii is an option. Any wonder why PH was surprised here?
2) Point: Given #1 above, the likliehood that Naval search was given a priority is low. I say this based on my assumption from above.
3) Fact: This is a game. Many of the arguments for or against the plausibility of a PF invasion are based on assumptions derived from RL. How many players truly behave as the commanders would have in RL?
4) Fact: For weeks, even months after the RL raid on PH the residents and military leaders in Hawaii lived in shear terror of an actual invasion by the IJ combined forces. Why do you suppose that is?
5) Point: Just because CD batteries were in place, whose to say the IJN would assault the most well defended beaches on Oahu? Given the exact nature of the intel they had for the RL PH raid, whose to say they wouldn't have the same intel on the most favorable landing spot? Furthermore, whose to say that the defenders would have all the ammo and supplies in place and said landing spot to put up a first rate defense in sight of KB and and the main battle line?
6) Fact: in the history of Amphibious warfare, no invasion was ever turned back by CD defenses.

[Mike Scholl]

ORIGINAL: TheElf

A couple facts....points.

6) Fact: in the history of Amphibious warfare, not invasion was ever turned back by CD defenses.

Fact: That's because no one was ever stupid enough to try one. The Normandy Landings were made BETWEEN the CD installations at Le Havre and Cherbourg.

[TheElf]

ORIGINAL: Mike Scholl

ORIGINAL: TheElf

A couple facts....points.

6) Fact: in the history of Amphibious warfare, not invasion was ever turned back by CD defenses.

Fact: That's because no one was ever stupid enough to try one. The Normandy Landings were made BETWEEN the CD installations at Le Havre and Cherbourg.

No one Mike? REALLY?!?! So then you must admit that the possibility that the CD routine is "flawed" is typical-Scholl-Alarmist "BS" (to use a Schollism). Unless, of course, you deny that the IJ combined forces would be smart enough to do the same...

Mike, your argument is semantics...my factual statement remains true, and your statement that "Nothing bigger than a 5" gun should be engaging PB's and such..., the rest should be blowing transports out of the water 10-20 miles out"...or..."if the game allows it to occur successfully any time after the morning of the 8th of December, 1941, then the game itself (specifically the CD vs. Invasion portion) is badly flawed"...or..."Those PB's and AK's should never have survived to get close enough to land anything but flotsom and jetsom from their sinkings, let alone "dueling" with the CD batteries"...or...."Nevertheless, you should have been butchered if the game's programming had been up to the task. Not your fault..., and you may have uncovered a loophole big enough to drive a tank through. So thanks for your efforts..., and the ball is now in the designer's court for correction...."------ That would all be predicated on the idea that the Japanese would attack NOT in between the CD defenses????

Which CLEARLY no one would be "Stupid enough to try". Right?

So which is it Mikey? Can't have is BOTH ways...[8|][:'(][:D][:D][:D][:D]

[Mike Scholl]

ORIGINAL: TheElf

ORIGINAL: Mike Scholl

ORIGINAL: TheElf

A couple facts....points.

6) Fact: in the history of Amphibious warfare, not invasion was ever turned back by CD defenses.

Fact: That's because no one was ever stupid enough to try one. The Normandy Landings were made BETWEEN the CD installations at Le Havre and Cherbourg.

No one Mike? REALLY?!?! So then you must admit that the possibility that the CD routine is "flawed" is typical-Scholl-Alarmist "BS" (to use a Schollism). Unless, of course, you deny that the IJ combined forces would be smart enough to do the same...

Mike, your argument is semantics...my factual statement remains true, and your statement that "Nothing bigger than a 5" gun should be engaging PB's and such..., the rest should be blowing transports out of the water 10-20 miles out"...or..."if the game allows it to occur successfully any time after the morning of the 8th of December, 1941, then the game itself (specifically the CD vs. Invasion portion) is badly flawed"...or..."Those PB's and AK's should never have survived to get close enough to land anything but flotsom and jetsom from their sinkings, let alone "dueling" with the CD batteries"...or...."Nevertheless, you should have been butchered if the game's programming had been up to the task. Not your fault..., and you may have uncovered a loophole big enough to drive a tank through. So thanks for your efforts..., and the ball is now in the designer's court for correction...."------ That would all be predicated on the idea that the Japanese would attack NOT in between the CD defenses?

Exactly true. Because they could not attack "between" the defenses on the island of Oahu because the whole island is part of the CD installation and covered accordingly. Yes, some areas weren't covered as well as others..., but that was because the reefs, beaches, and normal surf conditions made landings there extremely difficult most of the time. The areas where an invader could reliably plan an invasion were the areas covered most strongly.

Which CLEARLY no one would be "Stupid enough to try". Right? Absolutely right! Please name me the landings which prove otherwise if you disagree. One single landing against a major pre-war Coast Defense Installation like Oahu or Manila Bay or Singapore or Toulon or Tokyo Bay or San Francisco or Cherbourg or Vladivostok. Some were taken..., but always by an army landing a long way off and marching overland. That was true as far back as 1854 in the Crimea.

[aspqrz02]

ORIGINAL: Mynok

It appears that the Japanese used their barges as landing craft. Using the Daihatsu as a baseline, which has a capacity of 120 that's 120 men per craft.

According to Wikipedia, the Daihatsu 14m class could carry -

1 Type 95 7.4 ton tank or 70 men or 10 tons cargo

And had a range of 50 nm @ 8.5 kts (top speed) or 100 nm @ 7.5 kts.

(The Moku Daihatsu or 15m landing craft resembled the Allied LCVP, with a bow ramp that was lowered on hitting the beach. Unlike other Japanese landing craft, the Moku Daihatsu had a wooden hull, constructed of 0.4" (10mm) 5-ply plywood on oak frames and floors, thereby economizing on scarce steel. The hulls were weak and the wood quickly decomposed in the tropics, so that the craft were relegated to logistical support in calm waters.

The Navy ordered 1140 of these craft, but it is not known how many were actually completed.) -- from http://pwencycl.kgbudge.com/M/o/Moku_Daihatsu_class.htm

Unless you are referring to the Daihatsu 17m class which could carry -

1 Type 97 15.6 ton tank or 100 men or 16 tons cargo

Over the same range (again, according to Wikipedia)

(The Toku Daihatsu or 17m landing craft (Army Type N-L-BD) resembled the Allied LCVP, with a bow ramp that was lowered on hitting the beach. It was essentially a larger version of the Daihatsu and was built of welded steel. The Navy ordered 163 of these craft, but it is not known how many were actually completed (though at least 35 were built in 1943-44).

These craft were used extensively to run troops and supplies to isolated garrisons in the Solomons and elsewhere. The Japanese referred to these operations as "ant runs." As the war progressed, Allied air forces and PT boats became adept at intercepting and destroying these craft.) -- http://pwencycl.kgbudge.com/T/o/Toku_Daihatsu_class.htm

But the 17m model doesn't seem to have been available in any numbers, certainly not in early 1942!

Then there's the ...

The Chuhatsu or 13m landing craft was a smaller version of the Daihatsu used by the Japanese Navy. It resembled the Allied LCVP, with a bow ramp that was lowered on hitting the beach. It was used as a ship's boat for cruisers and for transporting aircraft. -- http://pwencycl.kgbudge.com/C/h/Chuhatsu_class.htm

With a capacity of 60 men or 10 tons.

Or the Daihatsu Class ...

The Daihatsu or 14m landing craft (Army Type LB-D) resembled the Allied LCVP, with a bow ramp that was lowered on hitting the beach. However, the Daihatsu was less boxy than an LCVP, giving it better seakeeping. It had a welded steel hull and was powered by a diesel engine. It was often field-modified to carry addition weapons of up to 37mm caliber, and the crew compartment was often protected with improvised armor.

The Navy ordered 3229 of these craft, but it is not known how many were actually completed (though at least 40 were built in 1942). The craft were so frequently encountered by Allied forces in the South Pacific, where they played an important logistical role, that actual construction must have been closer to the figure of 3229 than 40. Postwar the U.S. Navy Technical Mission determined that 85% of all Japanese landing craft were of this type.

Allied destroyers had a difficult time intercepting Daihatsu traffic in the Solomons. The improvised armor kept 40mm fire from being fully effective, and the landing craft were difficult targets for 5" guns because of their small size and high maneuverability. -- http://pwencycl.kgbudge.com/D/a/Daihatsu_class.htm

Which had a capacity of 1 Type 95 7.4 ton tank or 70 men or 10 tons cargo

So it would seem likely that the Japanese landing craft available for the PH operation in early 42 would have overwhelmingly been rated at only slightly over half of the troop capacity you are assuming.

Slows things down considerably, eh? [;)]

Phil McGregor

[Brady]

Excerpts from the linked threads below concerning Kota Baru:


Time table of Kata Baru landing

23:55 Tansports Anchored. Started launching landing crafts.
00:55 Finished launching. Moved troops to crafts.
01:14 Ready to go
01:35 Started to go to beach
02:15 Landing

Taki


So the total time for the operation was?

The landing after the first wave was postponed to the next day. So, the total time is meaningless.

> and their were 5,000 troops in all?

The most of 2,900 troops of the infantry regiment landed at the first wave.

Taki

...............

Six shipping engineer regiments participated In the early Paicific campaigns of the Malaya and Philippines and they and other shipping units had 315 Shohatsus and 312 Daihatsus. Besides them, IJN and SNLF had landing crafts.

As the war expanded to the Pacific Islands, more shipping units and landing crafts were required. Until the war ended, fifty and a few shipping engineer regiments were formed and approx. 6,000 Daihatsus were produced.

Taki

.................
Everything you ever wanted to know about Japanese Shiping Engenar Units:

http://forum.axishistory.com/viewtopic. ... it=Dihatsu

Notes on Japanese landing operations:

http://forum.axishistory.com/viewtopic. ... it=Dihatsu

The three craft below were the pimary IJA Landing Craft of the war, at wars start nobody was as well versed in Amphibious warfare or as well equiped or trained as the Japanese were untill 1943 when the US Begane to overtake Japan in terms of capacity and equipment.







..........

Comparasion:

[aspqrz02]

The "Type A" wasn't available until 1943-44 or later, as the sources cited elsewhere note ... the Handbook on Imperial Japanese Army produced by the War Department and similar pubs (where the illos are from, I presume) are very late war, and refer to the period 1943-44, not 41-early 42.

Phil McGregor

[Brady]

Selected Images of IJA Landing Crraft:

Dihatsu:



Toku Dihatsu:



Shohatsu



Unknown:



Beleaved to be during the Malaya operations:





Elements of the 48th IJA Divishion landing on Java:

[Brady]

ORIGINAL: aspqrz

The "Type A" wasn't available until 1943-44 or later, as the sources cited elsewhere note ... the Handbook on Imperial Japanese Army produced by the War Department and similar pubs (where the illos are from, I presume) are very late war, and refer to the period 1943-44, not 41-early 42.

Phil McGregor

Thats incorect they were used in all the initial operations in some numbers, the links above sight thier presence at various landings.

See:

http://www3.plala.or.jp/takihome/toku-daihatsu.html

Example from Linked Thread above:

> How Many Landing craft were part of this operation?

30 Toku-Daihatsus, 175 Daihatsus, 175 Shohatsus, 30 motor-barges(‹@•täx?M) were used in the Java Campaign.


Taki

[1275psi]

I don't really care about the argument -but Brady -fab photos and links -thanks!