FSO Proposal: Battle of the Bismarck Sea

[Saxman]

Background, per Wikipedia:

On 23 December 1942, the Japanese high command decided to transfer about 105,000 troops from China and Japan to Lae in New Guinea to reinforce their forces there. This would allow the Japanese to fall back from their defeat at the Battle of Guadalcanal, which they ordered evacuated the following week. The troops were needed near Lae, where an Allied offensive was expected.

Relocating such a large force was a great burden on Japanese shipping capability, but the high command considered it a military necessity. By late February 1943, the 20th and 41st divisions had been safely transported to Wewak, also in New Guinea.

The 51st Infantry Division had reached Rabaul safely in December 1942 and January 1943 and was originally intended to reinforce Japanese forces on Guadalcanal. With the Japanese withdrawal from that island, however, it was decided to send the 51st to Lae, New Guinea. The planned delivery of the division would be risky, because Allied air power in the area was very strong, especially in the Vitiaz Strait through which the ships would have to pass.

On 28 February the convoy assembled for the task, comprising eight destroyers and eight troop transports with an escort of approximately 100 fighter aircraft departed from Simpson Harbour in Rabaul. The commanding officer of the 51st Division, Lieutenant-General Hidemitsu Nakano, was aboard the destroyer Yukikaze, while Rear Admiral Masatomi Kimura, commanding Destroyer Squadron 3, was aboard the destroyer Shirayuki.

Allied air forces, under the air commander SWPA, Major-General George Kenney, and based in Allied territory on New Guinea, had been preparing for such an eventuality. In particular, the crews of specially modified USAAF B-25 Mitchells and RAAF Bristol Beaufighters had been practicing attacks on shipping. The Mitchell crews were developing a new technique called "skip bombing": after flying only a few dozen feet above the sea towards their targets, they would release their bombs, which would then, ideally, skip across the surface of the water and explode at the side of the target ship, under it, or just over it.

Allied Forces

USAAF
P-38J Lightning
B-24 Liberator
B-25 Mitchell
A-20

RAAF
P-40E Warhawk
Boston
TBM Avenger (torpedoes only, stand-in for the Beaufort torpedo bomber--yeah, yeah, Beaufort was a twin-engine bird, but our only twin-engine torpedo bombers are the Ju-88 and Ki-67)

Axis Forces

IJN
A6M2

IJAAF
Ki-61

Objectives:

Allies must attack Japanese shipping in the Bismarck Sea, represented by task groups consisting of destroyers only. The Japanese must defend the convoys.

[Krusty]

P-38s, A-20Gs, Bostons, B-24s, and P-40Es can all outfly the A6M2.

About the only thing it could catch would be the TBMs and (maybe) the B-25s (depending on alt situation).

[Anaxogoras]

Sub the A6M5 for the A6M3 and it might have a chance.  PTO setups are ridiculously one sided without the Ki-84 and N1K, even in early war.

[AKKuya]

This would require a 60/40 split in favor of the Axis for defending.  The 40% in Allied would have to be 50/50 between fighters and bombers.  This would be my first impression allowing either side a possibility of winning.

[gyrene81]

Looks like it could another fun one...just for FSO though might have to pump the numbers a bit since there were only a reported 268 total aircraft involved.


Allies
28 - P38G <---that was the model of the time period in the Pacific
25 - B-25C <--- non glass nose with 500 lbs bombs
13 - Mosquito MkVI (sub for Beaufighter)
13 - B17G <----should be F models
22 - RAAF Bostons
12 - B-24J (500 lbs bombs)
Unspecified number and variant of A20
Unspecified number of Bristol Beaufort torpedo bombers and only 2 made any contact

There is some reference to P-40s being involved throughout that period but the numbers are unknown.


Japanese:
100 - A6M5b <---could have been a mix with A6M2s


Since we don't have skip bombing...I wonder if it's possible to set the delay to 2 seconds to simulate skip bombing or just go with level and dive bombing.

Is it possible to have fleets without aircraft carriers in them?

Again, cool idea    be interesting to see how it would get put together.

[ghostdancer]

Yes, the CMs can destroy just the Carrier of a fleet leaving the CA and 4 DDs. Actually the CM can destroy each ship in the fleet individually.

As for skip bombing, correct we don't have it and we don't have a tool to force a 2 second delay on the bombs. So it would be the honor system which not really workable.

Currently we only have the Coral Sea terrain available. But since this is an exercise in design go for it. I will say that a terrain is under construction that would cover the area but have no idea on the timeline when it might be available. It is in the early stages of design.

Good discussion on planeset. I know there were a lot of obviously P40s based in Port Moresby. Not sure out about P-39Ds (P-400s). The P38G is sort of problematic in large numbers because of the Japanese aircraft but it is counter balance by the Ki61. So realistically it comes down to the min and max for aircraft to come up with a balance set.

A6M2s against P40Es or P39Ds is workable and has been in past FSOs. Although you could sub in the A6M5 instead which I would do if you have large numbers of P38Gs in the mix (even counter balanced by the Ki61).

The next issue is how to extend this into a three frame event. You might think of the actual battle as one frame out of three with a frame of the Japanese trying to soften up allied targets before the fleet comes in and US hitting Japanese targets in the area. Then in frame 2 have the fleet battle. Remember you have to come up with enough targets to spread out 250 players a side.

So a good starting point I would say.

[Soulyss]

I may be able to contribute more on the subject later tonight when I can sit down with some books and look some things up.  But speaking to the use of the P-39/P-400 they were still in widespread use at the time of the Battle of Bismark sea but were regulated to supporting operations on New Guinea since they did not have the range to cover the bombers all the way to their targets.  It probably would have been mostly if not all P-38's over the fleets.  There were a lot of supporting sorties flown to Japanese airfields on the NE coast of New Guinea to try and suppress Japanese air defenses.  If there was a terrain that could support it you could make the Battle of Bismark sea be the final climatic frame, the last Japanese attempt to reinforce their positions at Lae and Salamaua.


The 38's would have been G/H models and the 5th only had two squadrons available in March 1943, the 9th and 39th.
The B-25's would have been a combination of the glass nose and strafer configurations (the combat debut of the later)
B-17's were part of the battle while B-24's flew recon (in fact the fleet was first spotted by a B-24 from the 90th BG "Butcher Boy") I don't think any B-24's actually participated in the battle proper.

[Saxman]

The 38's would have been G/H models and the 5th only had two squadrons available in March 1943, the 9th and 39th.

Isn't the main difference between the H and J that the J was somewhat heavier with a different intercooler and ordinance loadout? I know I see a lot of 38H requests from the SAPP people suggesting the H would arguably outperform the J because of the weight difference.

I don't think any B-24's actually participated in the battle proper.

True, however we don't have the right model B-17 for ANY PTO setup, much less Bismarck Sea, so I'd say using the Liberator which is appropriate and omitting the B-17 entirely would be a workable compromise.

[Krusty]

Given the time frame, we don't have the proper B-24 either. So does it matter? Against A6M2s the B17 will rack up 50 kills and land safely. I see no difference in the slightly-faster B24's tally either.

[Soulyss]

Isn't the main difference between the H and J that the J was somewhat heavier with a different intercooler and ordinance loadout? I know I see a lot of 38H requests from the SAPP people suggesting the H would arguably outperform the J because of the weight difference.

Well it looks like it probably would have been G's not H's, according to another book here there's an entry that reads

Apr '43 Deliveries start of the P-38H Lightning model.

To answer your question the H model has the same engines as early block J 38's but retained the airframe of the earlier series.  So weight wise it would fall between the G and J but have a power output closer to the J, including WEP.  Historically the problem they ran into which prompted the change to the J was the intercoolers located in the leading edge of the wing could not keep up with the power increase of the newer engines, they moved them to the engine nacelles which is where the deep "chin" look of the J and L series comes from.

[Guppy35]

Not until we get Beaufighters!

RAAF Beaufighters were very busy during the Battle of Bismarck Sea

[Anaxogoras]

Not until we get Beaufighters!

RAAF Beaufighters were very busy during the Battle of Bismarck Sea

Yes, when we get Beaufighters.

[Squire]

With formations off you can have B-17s and B-24s in early PAC setups, you just have to be carefull with ratios, min-max #s ect. You have to look at the whole design.

[gyrene81]

Not until we get Beaufighters!

RAAF Beaufighters were very busy during the Battle of Bismarck Sea

It was Beaufort torpedo bombers...only 2 made any contact...and since they aren't part of the plane set...

Take the Bostons and P-40s.

The only P-39/P-400 units in the area were from the 8th FG stationed in Milne Bay (?) until sometime in December 1942 when they were sent to Port Moresby due to a high instance of malaria throughout the group. They did fly bomber escort and strikes against Japanese shipping. All 3 squadrons were re-fitted with P-38s in February 1943 and their P-39s went to a couple of RAAF squadrons for "home front defense". All other P-39s built from 1941 to around the time of the battle were allocated to training units and Russia.

So far that's the only accounting of P-39s in the area during that time with no mention of them being involved in the battle itself.

Since there were some good air/land events that happened in the days/weeks prior to the actual battle this could be a good Allied rolling plane setup. Using the Coral Sea terrain it could work out really well since Lae and Rabaul are on there. Japanese airplanes would be stationed at bases on New Britain...Allies based near Port Moresby
Frame 1:

Japanese - A6M2, Ki-61 (sub for Ki-43), D-3A1, B5N2.
Japanese own bases from just West of Port Moresby North along the coast of Lae.

Allies - P-40E, Boston III, A-20G, B-17G (8), B-24J (8), B-25C (8), 1 CV group, LVT-A2


Frame 2:

Japanese - A6M2, Ki-61 (sub for Ki-43), D-3A1, B5N2.

Allies - P-40E, Boston III, A-20G, B-17G (8), B-24J (8), B-25C (8)


Frame 3:

Japanese - A6M2, Ki-61 (sub for Ki-43), 2 CV groups (with no CVs)

Allies - P-40E, P-38G (28), Boston III, A-20G, Mosquito MkVI (13 - sub for Beaufort), B-17G (13), B-25C (25)


Split would be 60% Japanese - 40% Allied

Would that be workable and offer enough variety?

[Soulyss]

The only P-39/P-400 units in the area were from the 8th FG stationed in Milne Bay (?) until sometime in December 1942 when they were sent to Port Moresby due to a high instance of malaria throughout the group. They did fly bomber escort and strikes against Japanese shipping. All 3 squadrons were re-fitted with P-38s in February 1943 and their P-39s went to a couple of RAAF squadrons for "home front defense". All other P-39s built from 1941 to around the time of the battle were allocated to training units and Russia.

Actually only the 80th FS, 8th FG converted to the P-38 in early 1943 and flew it's first sortie with the Lightning on March 30th of that year. It wasn't until March 1944 that the entire 8th Fighter Group was converted to the P-38.  The 35th and 36th FS having made do with P-40's and P-47's in the mean time.  Although it was a high rate of malaria in the 80th that probably was cause of them receiving the P-38 before other squadrons in the group, Kenney could not pull the two more or less healthy units off the line to refit.

The P-39's were in service with the remaining two squadrons of the 8th FG through August 1943 and two squadrons of the 35th Fighter Group, the 40th and 41st.  The 39th FS of that group having been the first unit to become operational with the P-38.  The P-39's continued to see service until the end of 1943 with the last P-39 kills awarded to the 5th AF coming on August 14th, 1943. When P-39's of the 41st FS intercepted a raid over Wau and claimed ten "Lily" bombers and three "Ocscars", the 40th, arriving late to the scene claimed another three bombers and one Ki-43.

The 39's did not have the range to take place in the Bismark Sea battle, instead they mostly escort for C-47's on resupply hops to Wau and raids on Japanese bases along the New Guinea coast.