Coral Sea (Scenario 3) Human Allies v Hard AI

[Energisteron]

Day 4 - May 07

At dawn our habitual air raid from Rabaul arrives over Port Moresby. This time the Allied Ground Troops are the target. 26x Nells get clean through to the target despite continued heavy flak. We take no losses but results are impossible to evaluate.

Around the same time our main Invasion TF arrives off the beachhead at Port Moresby and prepares to unload in daylight. Above there is excellent fighter cover from Lae and CVL Shoho. Over at Buna our small slow reserve force sits in the bay unsure what to do but fortunately there is no shore opposition for the moment.

At first light search aircraft form Rabaul, Bettys, and Shortland, Mavis, detect the apparent enemy TF concentration seemingly still 200 NM south of Rossel Island.

[Energisteron]

Day 4 - May 07

Late in the morning our main Invasion TF commences a preparatory bombardment to which the Defenders reply quite effectively as our troops make for shore. Casualties are similar but represent a much smaller proportion of the force involved. However, CL Tenryu takes a shell hit and is holed below the waterline. For the moment she is still operational but is certainly at risk.

Meanwhile further off the coast xAK Canberra, abandoned and burning from stem to stern, slips below the waves.

After some apparent confusion about their orders troops are disembarked at Buna. In a heavy surf we take losses against zero opposition.

At dusk, the Australian defenders make a snap bombardment attack against the beachhead but by then we're well established ashore and losses are insignificant. Only stores and some larger devices remain to be unloaded.

[Energisteron]

Day 5 - May 08

Planning

So, we've landed at Port Morseby and appear to have a secure beachhead. Contrary to my earlier statement a few troops do indeed remain on board the Transports as well as the bulk of the supplies. Consequently, we must not rush into combat before we have regained composure after the trauma of the landings. We will therefore conduct bombardments only, supplemented by naval and aerial bombardment until our supplies are ashore.

CVL Shoho will move closer to the beachhead continuing to defend itself and provide CAP over the ground forces. She is not well screened with just one Destroyer, so a second will be detached from a Transport TF along with CL Tenryu which would be vulnerable to a second shell hit from shore. Going in the reverse direction to bombard the defenders at Port Moresby will be all four of CVL Shoho's accompanying Cruisers. Currently they've not fired a shot.

All Subs within 2 days' sail of the Enemy TF group will head that way and 'surround' them. Many have a spotter aircraft on board which could improve our chances of keeping the enemy detected. These aircraft will fly at night, weather permitting.

Faced with no military opposition our Ground Force at Buna will take over the town and facilities there.

Lae will continue to provide LRCAP over the Port Moresby beachhead and TFs. Rabaul Zeros will provide extra LRCAP for the Fleet Carriers, hepefully releasing more onboard Zeros for Escort duty. Nells will continue to strike at the defenders of Port Moresby, while Bettys will prepare to make a torpedo strike against any enemy targets found in their search zone (30 deg of arc either side of enemy's last known position. The Rufes have already gone to Tulagi but are short of aviation support. So, Shortlands will send one unescorted support vessel there while conducting ASW along its proposed route to Tulagi.

The Oiler will go to Truk to refuel. The surviving Transports and oddments from Tulagi will dock at Rabaul.

[adarbrauner]

All depends from where, when, and if, the AI shall send his Carrier Fleet; he can choose any launching location on sea at any time;

your CV task hasn't been spotted, has it?

[Energisteron]

When you asked the question, the answer was 'no, not yet spotted'.

That changed for both sides very early this next day!

[Energisteron]

Day 5 - May 08

The Outcome:-

Here is the news - 'The Japanese captured the insignificant base of Buna today, but discovered they only have a marginal superiority of boots on the ground at Port Moresby. Further east two Fleet Carriers from each side discovered each other shortly after dawn and commenced desperate attacks against each other. The US CAP prevailed and no Japanese aircraft made any direct attack on the Allied TF all day. In their first strike, the US Wildcats dealt with the defending Zeros while wave after wave of Dauntless and Devastators attacked both CVs Zuikaku and Shokaku, Both Japanese Carriers sustained hits but were still able to launch a counterstrike in the afternoon. However, again their efforts were dented by the Allied CAP and just two Vals and one Kate made an attack. Both Vals were shot down although a Val pilot did score one bomb hit on CV Yorktown. The US afternoon strikes were almost as powerful as those in the morning and further hits were made on both Japanese Carriers, particularly the CV Zuikaku, whose aircraft were forced to land on CV Shokaku or return all the way to Rabaul.'

We were unfortunate that bad weather over Rabaul prevented all flying after dawn at which point Bettys had spotted the US Carriers. A raid was launched immediately but returned to base because of bad weather having not relocated the enemy. The LRCAP of Zeros was sadly missed. That's no excuse however. The US pilots outfought and outflew the Zeros then picked their targets.

[In game terms, I had thought I'd kept my pilots fresh. None of the air groups had fatigue factors in double figures (except for the Zeros at Rabaul)]

Well, there must be some good news somewhere? I mentioned we captured Buna! I suppose we had quite a good day at Port Moresby. No significant losses, and more supplies now ashore. Both sides bombarded to little effect. We could have done with the air strike from Rabaul but weather prevented that operation today.

I'll present you with only the grimmest details. Below you'll find the first part.

At Port Moresby, all troops have reached the beachhead but 16.5k tons of supplies remain on board the Freighters, one of which is hit and severely damaged on its approach. We could lose the 2.5k supplies carried by xAK Kansai Maru. During the day defensive fire is much diminished and casualties are very light. At last all troops are now ashore but the supplies could take 3 - 4 days to unload.

[Aurorus]

Several observations. First, when you are playing the Grand Campaign and can sort your own force pool, you should be aware that Japan receives an amphibious bonus for the first 4 months of the war. During this period, you can use xAKs and all sorts of things to perform amphibious landings, because these ships receive a large bonus to their amphibious operations points. After this period, Japan does not have many ships capable of landing troops and supplies in a timely manner (very few LSDs). You want to use military AKs (not xAKs) at all times and APs. Also, do not fill every ship to its troop capacity and expect to debark in 1 day. Use more ships than necessary: again only AKs and APs. The large APs (troop capacity of 5K or so) should not be used for amphibious ops, rather as transport groups to move large LCUs from major port to major port. It will take these APs 3 days to fully unload their troops in an amphibious operation. Again, this is for when you can arrange your own force pool. From this scenario, you can see the problems that arise when you use cargo ships for amphibious ops as Japan.

Second, Japanese CVs pre July 1942 have small A6M2 complements. Two Japanese CVs against 2 U.S. CVs will place you at a severe disadvantage in fighters: 36 against 54. Again, keep your CVL with your CVs to increase fighter cover and escorts. Zeros are superior to F4Fs and your bombers are better so with even numbers of fighters you should do well in CV engagements. If the allies have a fighter advantage, all bets are off (as you can see).

Practicing CV engagements against the AI is not entirely helpful because the AI will always match your altitude. Several things about altitude. Japan has a litte more flexibility with its CV strikes than the U.S., because the U.S. is almost completely dependent on dive bombers, which means they must come in at 10K or above. Since most CVs have only 1 fighter group that must both CAP and escort, the U.S. must place all of its fighters at 10K or above. In general it is better to be a little above your enemy. However, if you patrol too high, enemy strikes can fly right under your CAP without the CAP ever engaging the bombers. Escorts for a low strike will climb and fight the CAP, but an unescorted strike can sometimes come right through if it is 10K or more below the altitude of the CAP. Torpedo bombers can come in at 1K or 2K altitude at times. The Japanese CVLs have only torpedo bombers and no dive bombers.

One tactic that I will sometimes employ as Japan is to place an entire CVL A6M2 squadron on CAP at high altitude (about 16-20K) and have the B5N2s set to naval strike at 1K. If used in conjunction with a CV group at 10-15K altitude, oftentimes this Kate group will come right in on allied CVs without being engaged by CAP. Another tactic that I like to use is have the CVLs set their A6M2s at 4-6K along with their B5N2s. If used in conjunction with CV strike groups and CAP set at 10-15K, this provides layered CAP over the CVs. What will often happen is that the CVL A6M2s will engage the DBs and TBFs as they go into their attack runs, rather than engaging the enemy escorts (some escorts will engage your CVL CAP, however, in diving attacks and you will take heavier losses than normal in these groups). Again, however, it is important to have your CVLs support your CVs, either in the same hex or an adjacent hex (same hex is usually better).

[Energisteron]

Thanks for a very detailed assessment of Carrier strike tactics, Aurorus.

I shall copy and paste that for reference and try to learn from it. All my strikes flew at 10-12k feet to the target although I did try to mix torpedo and dive bombers. It would have been interesting if the torpedo equipped Bettys had made it to their target!

[Energisteron]

Day 5 - May 08

Japanese Air Strikes against the US Carriers

At dawn Vals and Kates on Naval Search from Zuikaku and Shokaku, plus Bettys from Rabaul, located and identified the US Fleet Carriers in much the same position as the day before. We got in the first strike but to no avail! As described earlier, our bombers could not make it through to the target. Despite being damaged our Carriers launched another strike in the afternoon, but again results were catastrophically trivial, with just one single bomb hit on CV Yorktown resulting.

The enemy CAP was adequate initially but was reinforced to overwhelming proportions. Fighter losses were equal despite the US Wildcats enjoying a 4:1 advantage in sorties flown, but the bombers suffered badly (25% Kates and 55% Vals being shot down).

The last sighting of CV Yorktown seemed to indicate damage was minor. There were no secondary explosions or fires.

[Aurorus]

ORIGINAL: Energisteron

Thanks for a very detailed assessment of Carrier strike tactics, Aurorus.

I shall copy and paste that for reference and try to learn from it. All my strikes flew at 10-12k feet to the target although I did try to mix torpedo and dive bombers. It would have been interesting if the torpedo equipped Bettys had made it to their target!

Getting Netties to strike target with CAP, targets at long range (10+), and small TFs is an art. First, they must be at a base with an HQ, of course for torpedos but also to gain the benefit of the HQ leader coordination and strike attributes. Second, the air HQ commander must be aggressive: the more aggressive the better. In fact, Japan has only 2 air HQ commanders that are aggressive enough to launch Netties into CAP reliably. To strike targets at long range, you must have high Detection Level on the TF (6+), which usually means that search planes must be closer to the TF than the base from which the Netties launch. .

I have two unsubstantiated opinions that may or may not be true. It seems to me to be helpful if the Nettie pilots have high naval search skill and a small percentage of the squadron is actively naval searching. It also seems helpful if the squadron commander has a high naval skill. Again, this is unsubstantiated conjecture on my part... but I just had Netties put 3 torpedos into a BB at range 12 against CAP in one of my games... using all of these techniques. (Having a glen-equipped submarine patrol your Betty strike zone can be very, very helpful at increasing DLs... BTW... that is how I nailed this BB... the glen-equipped sub then hit a 2nd BB on her own the next night... very nasty... and effectively took the British Madascar TF out of the war).

[BBfanboy]

I think overall experience is what helps get hits, not the Nav Search or Naval skill of the leader (unless you mean NavB or LowN skill).
After watching many combat animations, I noted that if pilots misidentified the target ship class during a bombing attack they almost always missed. Initially I thought that must be related to their NavS skill, since higher NavS results in better ID of the ships sighted, but later came to believe it is the increased overall Experience that pilots get when cross trained to reasonable (50+) levels in several skills.

[Energisteron]

Hi again, Aurorus.

Thanks again for the insight. All interesting stuff. One can only learn by experience!

[Energisteron]

Hi BBfanboy

You've gone a bit beyond me there but I get your drift. In this scenario, of course, there's no time to improve experience, but as you correctly pointed out earlier, there's certainly time to fatigue your pilots!

I'm not dissatisfied by the way the game calculated the outcome of the Carrier battle. I think the results were entirely realistic, very much so. If my first strike had got a couple of hits it could have turned out entirely different.

[Energisteron]

Day 5 - May 08

The US Carrier strikes:-

Shortly after our first strike was repulsed without result, our own Carriers were attacked by an overwhelming air flotilla of 43x Dauntless dive-bombers escorted by 16x Wildcats. Our CAP took its toll downing 6x Dauntless and damaging another 11 but could do nothing to prevent the bombers getting through and hitting both Carriers and CA Myoko. Incredibly both Carriers remained operational but only just.

In the afternoon a second strike of hardly any lesser size resulted in some minor additional damage to the Carriers. We lost no Zeros on CAP to air-to-air combat in either raid.

At dusk, both Carriers were in a bad way. CV Shokaku still has considerable numbers of aircraft aboard (x46) including refugee aircraft from CV Zuikaku which has just 1x Kate in what's left of its hangers. If CV Zuikaku survives it will be a miracle! CV Shokaku may just make it to Rabaul but is likely to be pursued by the Allied TF throughout tomorrow.

[EDIT - error in graphic - Wildcat sorties numbered 29 not 16!)

[BBfanboy]

With 91 System damage and 60 fires, Zuikaku is doomed. Japanese damage control is just not up to miracles! You can save 10% of the VPs given to the enemy if you scuttle her - unless you want to use her as a bomb magnet to help save Shokaku! She may sink overnight anyway.

[Energisteron]

I would agree, BBf.

Thanks for the tip re saving 10% VP for scuttling. Something else that I'd missed. However, for the sake of 30-40 VP, I think we'll do our best to escape.

As for Zuikaku being a bomb magnet, I think that's inevitable if we try to get her away. Currently the friendly AI has detached both Carriers together into an Escort TF so Shokaku is shackled to Zuikaku's death knell speed of 6 knots. We will spit them so Shokaku at least has a chance!

[Energisteron]

Day 6 - May 09

Planning, or more accurately Emergency Planning!

I think the graphic says it all, but in brief:-

The two injured Carriers will separate and attempt to get to Rabaul with a little help with a land-based CAP of Zeros. The damaged Cruiser will dash for Truk. The intact Cruiser will take refuge in Lae. All subs will converge on enemy CVs.

We will make only a bombardment attack at Port Moresby which will be protected by CVL Shoho and attacked Nells from Rabaul.

[Energisteron]

Day 6 - May 09

The Outcome.

No need for a diagram today, since it turns out to be fairly quiet!

Unloading continues throughout the night at Port Moresby, and the defenders are still lobbing a handful of shells in our direction, but they really make them count! Approaching the beach for the first time, xAK Tatumiya Maru is hit twice (from 5 shots!) and set on fire but she remains operational for now. At dawn 16x Nells from Rabaul make a harassing air raid on the defenders with indeterminate results.

In daylight, unloading continues unabated, as does the fire from the shore. In an action bordering on folly, the already badly damaged, and several times extinguished xAK Kansai Maru is hit once more, and this time the damage is terminal. She immediately ignites again and sinks rapidly. She still held 2k tons of supplies in her holds!

During the afternoon, xAK Kasuga Maru is also hit once, and promptly bursts into flames. If the fires can be brought under control other damage isn't critical. Again she holds nearly 2k tons of supplies. In a retaliatory air strike, entirely at his own initiative, the Commander of CVL Shoho launches an attack against the port which has little effect. The defenders continue to fire 5-10 shells at each Freighter as she closes on the beach.

As per the emergency plan the Carrier TF was split into four TF; two TF with a single badly damaged Carrier head for Rabaul, one TF with a damaged Cruiser heads for Truk, and one operational Surface Combat TF of a single Cruiser which heads for Lae. The enemy seemingly do nothing to intervene, perhaps supposing the Carriers were beyond saving in any case, which proves partially correct, since as dusk approaches CV Zuikaku loses its battle with the inrushing sea and sinks. Hopefully the valiant damage control parties were rescued by the attendant Destroyers.

The status of CV Shokaku improves a little. The flooding is brought under control and all fires are extinguished. This comes at the expense of deterioration to her engines however, and her maximum speed is now just 22 knots. She is 120 miles from Rabaul in Sub infested waters! CA Myoko makes it through the Solomon Chain to the open sea to the east, and CA Haguro makes it to Lae. The 4xCA (unescorted) get through the straights NE of Lae without incident on their circuitous route to Rabaul (to avoid the enemy Sub cordon south of Rabaul). They badly need replenishment after expending over 80% of their main armament ammunition on bombarding Port Moresby.

Our gathering of Subs around the enemy Carriers is detected and one is attacked by a float plane but no damage results. Did this pack of Subs actually deter the enemy from pursuing our damaged Carriers?

So, the best we can hope for now is a Pyrrhic Victory; capture Port Moresby at the cost of two Carriers!

What is the enemy plan? It would appear to be to preserve their Carriers and not risk land-based (Bettys at Rabaul) air attack in order to punish our surviving Transports as they head home past Milne Bay. Well, maybe we won't go home! If we can capture Port Moresby airfield, and make it operational (we've not bombed it since their aircraft stopped flying from it), then we can fly in land-based bombers and fighters which would make it an intimidating target to take on, and we'd have a range advantage.

So, maybe it's still to be decided. Certainly at the moment the score looks very unhealthy (Allies 1428 : Japan 171).

By the way, while these dramatic events unfolded we slipped a platoon into the Russell Islands 80 miles NW of Tulagi. They're ours. All OURS!

[Energisteron]

Day 7 - May 10

Best laid Plans!

Surely the graphic tells all?

Hit Port Moresby. Mass Sub attack on enemy CVs. CV Shokaku to escape. And a vague plan to take Guadalcanal from Lae.

[BBfanboy]

Those 4 small CAs could have been better used by not bombarding PM (which wastes a lot of ammo in the jungle and on the already damaged airfield) but by embedding them in the landing TFs. They would then fire directly at the shore guns, suppressing their fire considerably. They would also absorb many of the hits that would otherwise be on the transports.

Learning all these nuances about amphib landings is why it is important for new players to play these small scenarios before tackling the big beast GC. It would be very discouraging to be 18 months into a Grand Campaign and lose a major part of your forces because you did not yet know how to arrange things for your campaign.