Amphibious invasion of Pearl Harbor - results

[Nikademus]

ORIGINAL: Blackhorse


If you beat the facts with a stick long enough, they'll confess anything. - Mark Twain

Truer words were never spoken. One reason why over use of the buzz word "Facts" on the Internet never fails to amuse me. My other favorite quote is "Statistics never lie.......people lie using statistics"

Using 290-380 invasion craft to put 100,000 men ashore in one day may pencil out on paper, but not IRL. By comparison, in 1944, with larger, purpose-built ships and craft, far better command and control, and the benefit of past experience, it took the Allies 3,500 landing craft to bring 175,000 men ashore in 24 hours at Normandy.

So, *if* the Japanese in early 1942 could operate with the same efficiency as the allies did in mid-1944, with a fleet of landing craft about 1/10th the size of what was used in Normandy, they might reasonable expect to unload about 17,500 men in a day, if losses to the landing craft are light.

Therin lies the rub....and its SAIEW from stock days. WitP represents mainly a paper/pencil estimate on lift capacity for amphibious invasion but with no real life govoner in place on the exponential increase in administrative and logistical difficulty of executing an amphibious assault or landing as you increase the troopage being landed. Its one thing to land a BN, its quite another to land a division....and still further to land 2+ divisions. The other issue is that landing craft are not specifically represented (either on map (impractical)) or in a pool (practical). Ultimately availability of landing craft was the biggest bottleneck of the war for the Allies in terms of size and number of Amphibious assaults that could be conducted. Overlord was originally to be 3 division landing, Monty expanded it to 5 which required further months of organization and planning and buildup. Morale of story. Protect your rear bases. This is one reason i never denude Pearl Harbor and in fact, reinforce it. Many players are determined to start Mac's drive on Japan as early as 1/42 with development and investment of bases on theoretical front lines that history has already revealed will be future points of contention. Not saying that happened here but it often occurs. Interesting that even in this example the base is not yet taken nor might not be.

[Feinder]

Certainly agree Hop. To be clear, I do NOT think that an invasion of PH ~shouldn't~ be possible (double negative such as it is). I'm just staying that the current model isn't reflecting accurately the losses that would be sustained in such an endeavor.

For one thing, true in WitP and appearently so in AE, CD guns only fire at the first 20 ships in the invasion TF. If you put 100 ships in the TF. The first 20 are going to get the crap blown out of them. But the other 80 usually get thru (altho they may be subject to mines, I haven't actually tested that yet). Probably something similar in AE (by observation). It appears that it's probably picking the sort order of the targets, simply by their sort order in the DB. So it might warrent a quick check to see if those PBs sort higher in the DB than the tranports, and you have test case for the target fixation on the PBs. Granted, the lack of fire against ~all~ ships in the TF (or at least more than 20), should also be addressed (so you're really looking at two issues or more).

As I said, I don't mind waiting for some "refinement" or mods to AE before taking the full swing of PBEM. My own perspective on WitP is that, combined with the engine patches, the CHS mod provided the best representation available. It wasn't without it's flaws. But over-all, it played the best of the various stock and mod scenarios. So in the case of AE, there ~will~ be mods. And I've some time to finish my current WitP PBEM game(s). So I'm in no rush.

-F-

[witpqs]

ORIGINAL: Feinder

Actually, Disabled is NOT dead (at least appearent in game terms). Destroyed is dead, and drains your pools. Disabled does NOT drain your pools, ie you are NOT drawing replacements. Disabled may mean anything from non-critical wound to loss of cohesion to scattered to unaccounted for. But if you put that unit same unit in a non-malaria base with an HQ, it actually regains fairly rapidly (at least in my experience). It might take 3 weeks, which in my opinion is a reasonable time.

I will say that while I do think the model is borked (by observation of these threads, that I am in no rush to begin PBEM in AE), if you do increase the destroyed squads results to be more realistic, you'd also have to adjust the replacement squad availability (which I have been reviewing to OBs, and replacement squads are certainly too anemic to begin with, much able to withstand an accurate combat model).

-F-

F - I want to expand on one aspect of what you wrote. Going by prior documentation and forum explanations, disabled squads can represent squads with wounded and dead, and the replacement people are abstracted by supply. So no, the entire squad is not "dead", but disabled squads can and often do represent dead individuals. I only mention it because there seems to be some interpretation of disabled squads as "no deaths", and in some actions that's difficult for people to accept. (Just to be clear, I think the landing this thread is about had way too few casualties, I just want to clear up a point of understanding.)

[bradfordkay]

Feinder wrote:

"For one thing, true in WitP and appearently so in AE, CD guns only fire at the first 20 ships in the invasion TF. If you put 100 ships in the TF. The first 20 are going to get the crap blown out of them. But the other 80 usually get thru (altho they may be subject to mines, I haven't actually tested that yet)."

Interesting point. It seems that in WITP people were calling the use of multiple TFs to invade a single location "gamey" whereas your observation lends credence to the thought that this would be more realistic. I suppose the attitude differs in whether the defender is relying upon air attacks or CDs to defeat the invading forces... just another of the trade-offs we have to deal with in creating/playing a game of this magnitude...

[Feinder]

Thank you for the clarification witpqs.
Brad - Multiple TFs to invade: It one of those things where, if you have 3x 100-ship TFs, the first 100-shipt TF lands. The first 20-ships of that TF are going to have a very bad day. The other 80 land whatever. The 2nd 100-ship TF lands. The CDs are somewhat disrupted, so the effect on the first 20-ships of the 2nd TF will be less than the damage of the 1st TF. Either way those 20-ships are the primary target, and the 80-ships of the 2nd TF make their landing. Then same routine, vs. more disrupted CD guns on the 3rd TF.

I will put the caveat (sp?) - before everybody put the kaibosh on 100-ship TFs, you have to consider what is needed for the barges/LCTs etc. YOu need scads of those things, limiting a TF to 20-25 ships would necessitate a bunch more TFs when using barges (even more unwieldy). The solution would be to actually make CD guns fire at all (or most) of the ships in the TF.

My 2-pfennigs.
-F-

[bklooste]

ORIGINAL: Mike Scholl

ORIGINAL: TheElf

ORIGINAL: Mike Scholl





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.

This is clearly incorrect most of the northern beaches were almost unguarded early in the war and their are few reefs there in fact most of the reefs are in the SOuth right under the guns , how many times does it have to be said the guns were their to protected PH from shelling from a battle fleet and not an invasion of Oahu. Ok maybe 1 heavy battery at Maximum range firing at the beach indirect over the mountain range ( not the ships but the landing ) so that aint going to do much good and i doubt they will have spotters for long ( except for spotting planes).

You would have to be an idiot to land on the south when you can land on the nice beaches of the NE , the mountain helps secure your flank and covers your landing (with a small amount of troops ) , follow the beaches a bit SE and then a short trip West to PH. This is just like D-Day the only issue is landing suplies ( in the game rules this is easy ) though historically they could have run barges ( ie siezed ships ) from Lahaina.

I still dispute the effectiveness of most of these CD guns especially at night, the ones at the english Channel ( on both sides) couldnt hit a barn and ships conitnued to use the channel ( from both sides) despite the guns hitting the other side. Considerign a Japanese night landing on the North side of Oahu ( ie at maximum range) , how well will they target the star shells ? Do they have 16" star shells ? I doubt the star shells will even get close. Once the Japanese are ashore your not going to have many spotters due to the terrain ( except for aircraft) ... You cant see it you cant fire on it. Even in daylight i doubt the range finders were facing North of the (Kolau?) mountains or were setup for indirect sighted fire .

Anyway the point is moot the game engine does not Model Oahu but a typical coastal hex.

[herwin]

ORIGINAL: bklooste
...

This is clearly incorrect most of the northern beaches were almost unguarded early in the war .. And certainly not covered by the heavy CD guns. You would have to be an idiot to land on the south when you can land on the nice beaches , the mountain helps secure your flank and covers your landing (with a small amount of troops ) , follow the beaches a bit SE and then a short trip West to PH. This is just like D-Day the only issue is landing suplies ( in the game rules this is easy ) though historically they could have run barges ( ie siezed ships ) from Lahaina.

See this site for why the North Shore was not at risk until April, 1942. The Japanese lacked the capability of landing supplies on an undeveloped beach, and the waves on those beaches were enormous.

[herwin]

ORIGINAL: Nikademus


Therin lies the rub....and its SAIEW from stock days. WitP represents mainly a paper/pencil estimate on lift capacity for amphibious invasion but with no real life govoner in place on the exponential increase in administrative and logistical difficulty of executing an amphibious assault or landing as you increase the troopage being landed. Its one thing to land a BN, its quite another to land a division....and still further to land 2+ divisions. The other issue is that landing craft are not specifically represented (either on map (impractical)) or in a pool (practical). Ultimately availability of landing craft was the biggest bottleneck of the war for the Allies in terms of size and number of Amphibious assaults that could be conducted. Overlord was originally to be 3 division landing, Monty expanded it to 5 which required further months of organization and planning and buildup. Morale of story. Protect your rear bases. This is one reason i never denude Pearl Harbor and in fact, reinforce it. Many players are determined to start Mac's drive on Japan as early as 1/42 with development and investment of bases on theoretical front lines that history has already revealed will be future points of contention. Not saying that happened here but it often occurs. Interesting that even in this example the base is not yet taken nor might not be.

For the MIFASS and TCO systems (which were designed for USMC MAGTFs ranging from battalion--MEU--to corps--MEF), we simply scaled up.

[Mike Scholl]

ORIGINAL: bklooste

This is clearly incorrect most of the northern beaches were almost unguarded early in the war and their are few reefs there in fact most of the reefs are in the SOuth right under the guns , how many times does it have to be said the guns were their to protected PH from shelling from a battle fleet and not an invasion of Oahu. Ok maybe 1 heavy battery at Maximum range firing at the beach indirect over the mountain range ( not the ships but the landing ) so that aint going to do much good and i doubt they will have spotters for long ( except for spotting planes).

Actually, if you would bother to check, you would find that the beaches outside of the South Shore area were covered by approximately sixty 8", 6.1", 6" and 5" CD guns in 1942 as well as the winter surf conditions. More than enough to make life exciting and short for any wandering Japanese AK or AP.

[John Lansford]

The North Shore of Oahu was protected by something more formidable than CD installations.  Got to Google Maps and look at that shore of modern day Oahu; see any piers or port facilities?  See those big white lines of surf just off shore?  Those are 15'-30' waves, and from December to April the Pacific storms kick them up constantly.  Even the rest of the year they're 12'-18' high, more than enough to swamp any landing craft trying to beach itself on the shore.  The reason why the Army built some CD facilities covering the North Shore was because it was just possible that a raiding force might be able to get to shore and cause trouble. 

If the Marines thought it insane to try a landing on the North Shore, I'd tend to trust their judgment and accept that the NS was an unsuitable location for large scale amphibious assault.

[Bearcat2]

List of the Defenses/guns, with dates.
http://www.cdsg.org/hawaii.htm

North Shore defenses:
http://www.northamericanforts.com/West/hi-north.html

[undercovergeek]

anyone actually succesfully attack the island yet - not just get off the boats?

[Blackhorse]

ORIGINAL: Termite2

List of the Defenses/guns, with dates.
http://www.cdsg.org/hawaii.htm

North Shore defenses:
http://www.northamericanforts.com/West/hi-north.html

That was one of the primary sources in developing the Coastal Defense TO&E for Oahu. One correction/clarification to the list of defenses. The site says:

Oahu howitzer positions manned by field artillery units ?
Kalihi/ 2-240 mm/ H/ 1941-1944 / Kalihi, atop Koalau Range
"Quadropod"/ 2-240 mm/ H/ 1941-1944/ Paalaa
unnamed/ 2-240 mm/ H/ 1941-1944/ Kole Kole Pass
unnamed/ 2-240 mm/ H/ 1941-1944/ Kunia

There were 12 WWI-era 240mm M1918/1920 Howitzers on Oahu, as part of the Coastal Defenses. These "Super-Heavy Artillery" pieces really weren't field artillery. The site correctly notes that there were 8 emplacements for these howitzers. In AE, they are assigned the same stats as the 240mm "Black Dragon" howitzer that was first fielded in 1943 (in Italy) and becomes available in limited numbers for the Americans in late-1944.

bklooste: Considerign a Japanese night landing on the North side of Oahu [snip]

The North Shore of Oahu was not a practical landing site for a major invasion, for all the reasons mentioned above. And no country would consider making a major invasion primarily at night -- certainly not in early 1942. It was hard enough to land on target in daylight (and units frequently landed miles from where they were supposed to). Nightime landings would have been a nightmare.

[Brady]

ORIGINAL: Blackhorse



The North Shore of Oahu was not a practical landing site for a major invasion, for all the reasons mentioned above. And no country would consider making a major invasion primarily at night -- certainly not in early 1942. It was hard enough to land on target in daylight (and units frequently landed miles from where they were supposed to). Nightime landings would have been a nightmare.

As you can see from the map I posted before Only the south shore was protected to any apricable extent, all the other shore lines of Ohau are only covered by a very few guns at wars start.

All the Japanese landings were done at Night, I gues you would have to define what was Magor, Landing a Divishion or two at night at multiple locations simultaniously is not Magor?

Prety much every landing Japan made was over an undeveloped beach head, Entire Campagines were suported in this maner.

I think for the sake of argument if you were going to land on Ohau as the Japanese it would have to be asumed that the KB would of gained Air Superority and theirfore largely nutralised the CD instalations.

The only perioud this would of even of been practile would of been at wars start imo.

In game terms Shore condations are not a consideration.


.........

I just did a quick look with Google earth and Oahu is definatly not ringed with Beaches, howeaver at wars start even along the SW and Western Shore line whear their are very few guns actualy covering these spots their are some very decent looking beaches, Isolating a CD posation or two and paying it special atention would of certainly be doable.

[Brady]

The Source

[oldman45]

I wonder if they could have moved so many ships with complete radio silence. I think the OP mentioned over 300 ships, thats a lot of refueling at sea, not to mention trying to shepherd them along. I know the allies dropped the ball, ie patrol with air/subs etc, i just wonder if he had looked at his intel if something would have been mentioned, I am reasonably sure that in RL something would have come up [;)]

[herwin]

ORIGINAL: oldman45

I wonder if they could have moved so many ships with complete radio silence. I think the OP mentioned over 300 ships, thats a lot of refueling at sea, not to mention trying to shepherd them along. I know the allies dropped the ball, ie patrol with air/subs etc, i just wonder if he had looked at his intel if something would have been mentioned, I am reasonably sure that in RL something would have come up [;)]

Not a chance, especially as a lot of the ship captains would have been civilians.

[John Lansford]

ORIGINAL: Brady


The Source

Well that was certainly an interesting "what if" scenario, unfortunately based on the IJN and IJA being perfect, coordinated and experts at every single phase of that operation, and the USN and USArmy a bunch of complacent, bungling and overconfident goof-offs.

It would seem to me that an armed landing on Johnston and Kauai islands would be a dead giveaway to Japanese intentions, and the defenses of Oahu and other islands adjusted to take that into account. Once that's happened, all bets are off on Oahu's defenses being in the same condition they were in prior to 12/7/41. The beaches will be defended and mined offshore very quickly, camoflage installed at all CD positions and mobile guns dug in and sited, and any possible reinforcements on the WC released to be sent there.

[wpurdom]

Although I think the Landsford-Herwin line of analysis is more likely correct, it seems there's an unwonted level of certainty in all this analysis. In the first three months of the war, the Japs came up with a variety of low tech innovations that magnified the effect of of their offensive - the bamboo contraptions that allowed torpedoes to be dropped at 3 times the speed the Allies could, the innovations that made torpedo runs possible in the harbor, the special one-time horizonal bomb AP bombs for the PH attack, the low-tech accellerated landings pulled off at a rate the Allies could have never matched, the bicycle troops, etc.

Here are some of the vulnerabilities of confidenece. First, I think it is an illusion that the Japs could not have found out the details of any pre-war military installations of interest to them. There are no comparables to such a landing to judge by. In January 1942, the competance and command and control of the US Army was a low ebb with large influxes of untrained leaders in jobs they didn't know how to do. It's unlikely that the USA did realistic anti-invasion planning and training, since at the time only the Marines knew anything about the requirements of carrying out an invasion. If you plan the invasion pre-war perhaps there is some creative way to disrupt the command and control, observation etc. like the Germans did moving into Holland and Belgium by paratroop.

I'm not saying that the CD model isn't off when faced with this scaled up situation. It's more likely than not its way off on a 100 ship Japanese invasion - not to mention that they didn't have the background that the US did in 1944. But a little humility is in order about the certainty that the US Army could have competantly coped in January 1942 with an invasion as meticulously planned as the attack on Pearl Harbor is in order.

The invasion would have never happened IRL, due to the political division of the Japanese command. But we have already magically erased that factor, which is the principle reason that Japanese players can in WTIP transcend the performance of the real life, unsupported IJN.

[Blackhorse]

In game terms Shore condations are not a consideration.

Be careful with using "game terms" to support your line of arguement, pardner. [:)]

In game terms, all units in a 40nm hex can engage all other units -- which you are contending should *not* be the case when CD guns engage invasion fleets.

As you correctly note, the primary role of CD guns is to protect the port. Since the game allows any bombardment TF -- including, fx, a bombardment TF supporting an invasion of the North Coast, presumably out of range of the big guns -- to shell the port, in game terms, the CD unit needs to be able to fire back at those TFs. Or AE needs a lot more coding (*shudder*) with different rules for how CD guns engage Amphibious TFs.

Now if only Oahu had been split into two different hexes . . . [8D]