The Singapore Logistical Battle

[Fatboy Coxy]

We often see TL’s that explain how Malaya could have been saved, but they all focus mainly on the fighting. Little is given to the logistics. So I’d like us to talk more about the logistical problems faced by both the Allies and the Japanese.

OK its 1st February 1942, let’s say after a reasonably successful Operation Matador, the British have gradually withdrawn to say the river Muda, border of the states of Kedah and Penang. And the British forces in Kelantan (Kota Bharu) have withdrawn.

The British have already committed the Australian 8th Division to the fight, along with both the Indian 9th and 11th Divisions, and have rotated their other units, leaving all battle weary. Ammunition is low, the RAF are only able to maintain air superiority over Johore and Singapore. The bomber and torpedo sqns are badly low on aircraft and aircrew. Force Z was not lost, both POW and Repulse remain, but are now back in Ceylon.

Japan finds herself in control of Thailand, but the single rail track south is only good to Hat Yai. The port of Signora has been badly damaged, with several sunken ship obstructing the port roads. She is in control of Kelantan and her three airfields there. She also has Alor Star in Kedah. However the British have not left any supplies, fuel, munitions, all airfield have been had the infrastructure damaged, grass runways ploughed up, while the railway has been extensively destroyed, along with many bridges. Both the 5th and 18th Divisions have taken heavy losses, and need rest and replenishment, with the Imperial Guard Division holding the line. Both the IJA and IJN air forces have also taken high losses and are in desperate need of replacement aircraft and aircrew.

So with stalemate for both land and air forces in Malaya, lets look at the rest of the theatre. In Burma, the Japanese are advancing to the Sittang river, but already do not have the supplies to exploit any successful river crossing. In the Philippines, it is as was, fighting going on in the Bataan peninsula. Borneo is just about being completely overrun. The IJA are not making any more troops available until they can resupply and continue the campaigns in The Philippines and Malaya.

Both sides must resupply, but the IJN fleet remains very potent, with few losses.

OK so on the allied side, where are convoys marshalled, what routes do they take, what escorts can they be given? Both Java and Sumatra will have to be partly held I guess, especially the Sunda Straits? What forces must be diverted to try to help them remain in allied hands. How big are the following threats, IJN submarines, IJN seaplanes, IJN land based aircraft, IJN southern force, Kido Butai.

For the Japanese, where are the convoys marshalled, what route do they take, what escorts can they be given? How big are the following threats, Allied submarines, Allied land based torpedo bombers, Allied land based bombers, Allied surface ships (British, Australia, Dutch, US) in theatre, US Carrier forces, newly forming RN Eastern Fleet in Ceylon.

I know there’s a lot here, and its going to get messy, but please try to remain within scope.

Regards

Fatboy

 

[fester]

We often see TL’s that explain how Malaya could have been saved, but they all focus mainly on the fighting. Little is given to the logistics. So I’d like us to talk more about the logistical problems faced by both the Allies and the Japanese.

OK its 1st February 1942, let’s say after a reasonably successful Operation Matador, the British have gradually withdrawn to say the river Muda, border of the states of Kedah and Penang. And the British forces in Kelantan (Kota Bharu) have withdrawn.

Both sides must resupply, but the IJN fleet remains very potent, with few losses.

OK so on the allied side, where are convoys marshalled, what routes do they take, what escorts can they be given? Both Java and Sumatra will have to be partly held I guess, especially the Sunda Straits? What forces must be diverted to try to help them remain in allied hands. How big are the following threats, IJN submarines, IJN seaplanes, IJN land based aircraft, IJN southern force, Kido Butai.

For the Japanese, where are the convoys marshalled, what route do they take, what escorts can they be given? How big are the following threats, Allied submarines, Allied land based torpedo bombers, Allied land based bombers, Allied surface ships (British, Australia, Dutch, US) in theatre, US Carrier forces, newly forming RN Eastern Fleet in Ceylon.

I know there’s a lot here, and its going to get messy, but please try to remain within scope.

I am struggling with this question for my timeline. I look forward to see what comes of this. I am using http://www.netherlandsnavy.nl/Singapore.html as a decent starting point as a resource for this question.

As I see it, there is an increasing concentration of Royal Navy combat power in Ceylon (Force Z + Armored Flight Deck Carriers +Warspite). Indomitable was already being used as a fighter ferry by February 1, 1942. There is also a decent number of units from the Mideast and India that are available to move. I think most of the convoys will be staging from either Bombay or Ceylon for the Indian based convoys as well as Sydney for the Australian convoys. The Sunda Straits are the safest path so that means holding western Java and eastern Sumantra are critical. I think that task gets easier in your scenario than OTL as the Malayan campaign is only going badly for the British instead of being a complete CF.

I think the biggest threat to RN escorted convoys (assuming Sunda Straits are open) is the KB coming south but they don't want to play in confined waters with significant enemy air units. In many ways, the Singapore resupply problem is similar to the Malta problem but in this case, the Sumantran coast takes place of the Tunisian coast so it is easier. The convoy attackers are the tail end of an extreme logistics chain so their ability to generate repeated strikes will be challenging. The biggest problem is that if the land based air flotillas can locate a force, the RN won't have the fighter numbers to break up an escorted Betty attack with any degree of confidence.

 

[Antiochus V]

You can get a good feel for the Singaporean side of things by playing War in the Pacific. It makes you appreciate how precarious Malaya became when Thailand joined the Axis powers. It also answers some of your questions on routes and marshaling points. For what it is worth it helped me work out the logistics angle when I did a timeline on the topic, which was carefully considered.

The sea route to Singapore is vulnerable and very risky in the absence of significant air cover. Rangoon is also exposed though not as badly, but it is key as the overland route from India is pretty hopeless. Allied airfields to the east (Borneo and Brunei I think?) would have slowly fallen making Singapore even more vulnerable.

The Dutch had submarines, the British did not initially. The US did have submarines but their torpedo problems were very serious.

The Japanese position relies on small coastal ports and the Thai railway system. The Thai railways are a weak point and in a protracted campaign as I think they would become vulnerable to air attack. The Allied air presence was a bit deficient, lacking numbers, quality and range.

Burma has somewhat weak transport links to Thailand, which would have been a serious constraint had the British possessed an extra division in Burma. Perhaps if the 18th division had gone there (instead of Malaya) with the 7th Armoured brigade the Japanese would have been blocked.

 

[Peg Leg Pom]

OK so on the allied side, where are convoys marshalled, what routes do they take, what escorts can they be given? Both Java and Sumatra will have to be partly held I guess, especially the Sunda Straits? What forces must be diverted to try to help them remain in allied hands. How big are the following threats, IJN submarines, IJN seaplanes, IJN land based aircraft, IJN southern force, Kido Butai.

If Malaya and Java are in allied hands Sumatra is safe. With much of Malaya in British hands the Japanese can't get sufficient forces into Northern Sumatra to take the island. Hold Java as well and the Sundra Strait is open to allied shipping. The Key action to secure the supply line to Singapore is the Battle of the Java Sea. If Kido Butai are involved then the ABDA naval force is in trouble even with Force Z and presumably a carrier. They need to take out any Japanese carriers before they themselves are found. That means a night strike as the Fleet Air arm aircraft are badly outclassed. In a daylight carrier engagement the Japanese will win. In that case the ABDA have to withdraw, they can't survive in the face of Kido Butai air power, and in all likelihood Java will fall and the whole Malay Barrier will follow.

 

[Anarch King of Dipsodes]

We often see TL’s that explain how Malaya could have been saved, but they all focus mainly on the fighting. Little is given to the logistics. So I’d like us to talk more about the logistical problems faced by both the Allies and the Japanese...

What we've got here is weakness versus weakness, which IMO is much harder to resolve than strength versus strength.

 

[Fatboy Coxy]

What did occur to me while researching available cargo and troopships, was the quality of merchant ships in general in the India Ocean. Clearly the bigger and faster ships, and more likely newer ones had been hand picked for the Malta runs in the Med and most of the rest to be found on the Atlantic convoys. I then thought about what the US could provide, but whereas these days there must be an enormous amount of shipping between North America and Japan, Korea and China, in 1942 there was none! and indeed had been vey little for some time due to economic blockade. So large quantities of merchant shipping would not be available, only enough for peacetime operations.

The US in fighting the Pacific war, had considerable difficulty assembling a sufficient fleet train, and would need a year, 1943, I guess before they could mount sustained operations. What we saw happen was the Japanese advances slowed down due to their logistical problems, along with stiffening Allied resistance. And gradually the Allies built up their strength. The British in Burma, took even longer, in part due to terrain and poor logistical network.

So in this timeline, demands have to be made on other theatres. OK the biggie, Europe First! how does that stand with this situation. The British cannot give up Malaya, indeed with the sucking in of Australian assets, ie I Australian Corps, into possibly Malaya or Dutch East Indies, the commitment grows. We saw the diversion of assets bound for the Middle East, like British 18 Division, and aircraft taken from the Middle East theatre. In North Africa the front line was at El Agheila by Jan 1942. Clearly the Japanese coming into the war had an effect on this theatre, but in the suggested TL, this will be even greater.

Something I've read in posts previously is that Operation Torch would have to be cancelled. Well that's late 1942, and I can see that not even being considered, indeed given the need to divert shipping from the Atlantic Convoys, we could see no Dieppe, and a reduced effort by Bomber Command.

Some supplies can be provided by India and Australia, but the main has to come from the UK and USA. With the main merchant fleets in the Atlantic, this would mean more WS coded convoys around the Cape of Good Hope. Freetown, Sierra Leone, a major refuelling point, was already a bottleneck, while WS convoys reaching South Africa had to be split between Cape Town and Durban as neither could handle their size. If we look to supply from Western USA, its a big leg to Hawaii, and then Fiji, on to Auckland maybe, which will only take a limited sized convoy. And these a big journeys, make the Atlantic crossing look like a small hop. They are going to gobble up ships!

Japan has her own problems. She never had enough merchant ships to start with. The IJN didn't want to commit to convoys, it didn't have the resource to effectively escort them, and it didn't have the organisation to manage a systematic use of convoys. We all bemoan Japans lack of effort in this, but convoys are massively inefficient in regard to logistical needs. They create bow waves of supplies that swamp local networks, supplies are delayed while convoys marshal, and everyone sails at the speed of the lowest. While the mainly US submarine force, due to faulty torpedoes, was ineffective, in 1942, it may have been better to accept those losses in the short run. And ports, where supplies were headed to, could be downright basic, delivering over a beach for instance. I also notice how Allied ships scuttled early in the war were raised and repaired as a part answer of Japans desperate need to find more ships.

In addition you have the whole inefficient rivalry of the IJN and IJA, with the IJA having its own ships! And given a strategic plan that was always being changed, adding more commitments to an already over taxed logistical network.

 

[Antiochus V]

What did occur to me while researching available cargo and troopships, was the quality of merchant ships in general in the India Ocean. Clearly the bigger and faster ships, and more likely newer ones had been hand picked for the Malta runs in the Med and most of the rest to be found on the Atlantic convoys. I then thought about what the US could provide, but whereas these days there must be an enormous amount of shipping between North America and Japan, Korea and China, in 1942 there was none! and indeed had been vey little for some time due to economic blockade. So large quantities of merchant shipping would not be available, only enough for peacetime operations.

The US in fighting the Pacific war, had considerable difficulty assembling a sufficient fleet train, and would need a year, 1943, I guess before they could mount sustained operations. What we saw happen was the Japanese advances slowed down due to their logistical problems, along with stiffening Allied resistance. And gradually the Allies built up their strength. The British in Burma, took even longer, in part due to terrain and poor logistical network.

So in this timeline, demands have to be made on other theatres. OK the biggie, Europe First! how does that stand with this situation. The British cannot give up Malaya, indeed with the sucking in of Australian assets, ie I Australian Corps, into possibly Malaya or Dutch East Indies, the commitment grows. We saw the diversion of assets bound for the Middle East, like British 18 Division, and aircraft taken from the Middle East theatre. In North Africa the front line was at El Agheila by Jan 1942. Clearly the Japanese coming into the war had an effect on this theatre, but in the suggested TL, this will be even greater.

Something I've read in posts previously is that Operation Torch would have to be cancelled. Well that's late 1942, and I can see that not even being considered, indeed given the need to divert shipping from the Atlantic Convoys, we could see no Dieppe, and a reduced effort by Bomber Command.

Some supplies can be provided by India and Australia, but the main has to come from the UK and USA. With the main merchant fleets in the Atlantic, this would mean more WS coded convoys around the Cape of Good Hope. Freetown, Sierra Leone, a major refuelling point, was already a bottleneck, while WS convoys reaching South Africa had to be split between Cape Town and Durban as neither could handle their size. If we look to supply from Western USA, its a big leg to Hawaii, and then Fiji, on to Auckland maybe, which will only take a limited sized convoy. And these a big journeys, make the Atlantic crossing look like a small hop. They are going to gobble up ships!

Japan has her own problems. She never had enough merchant ships to start with. The IJN didn't want to commit to convoys, it didn't have the resource to effectively escort them, and it didn't have the organisation to manage a systematic use of convoys. We all bemoan Japans lack of effort in this, but convoys are massively inefficient in regard to logistical needs. They create bow waves of supplies that swamp local networks, supplies are delayed while convoys marshal, and everyone sails at the speed of the lowest. While the mainly US submarine force, due to faulty torpedoes, was ineffective, in 1942, it may have been better to accept those losses in the short run. And ports, where supplies were headed to, could be downright basic, delivering over a beach for instance. I also notice how Allied ships scuttled early in the war were raised and repaired as a part answer of Japans desperate need to find more ships.

In addition you have the whole inefficient rivalry of the IJN and IJA, with the IJA having its own ships! And given a strategic plan that was always being changed, adding more commitments to an already over taxed logistical network.

I really recommend playing War in the Pacific, if you like the period and are curious as to what ships were available you will be quite impressed. There actually was a fair bit of shipping in the area at the start of hostilities, and as you say it tended to be on the slow side. I always felt when playing that the biggest issue was a lack of escorts.

 

[Fatboy Coxy]

So the more I ponder this, the more I feel the British and Dutch have to weather a storm, namely the Kido Butai. How far south might they come. In the suggested timeline the RAF have a working early warning system with Radar, giving their Hurricanes and Buffalos time to get airborne and affect a good intercept off shore. There would be very few bomber assets, but a steady flow coming as was historically. The obvious comparator is the Ceylon raids.

And the KB would have to be doing this without a IJA invasion force being available, so this does in effect become a raid.

 

[dave_r_gilbert]

Because the Kido Butai missed the US carriers at Pearl anything they do has to be a raid and no more.
Once they have gone south the USN can interrupt whatever is happening further east.
From December to June the Kido Butai was busy in OTL, so if they go south ITTL something else doesn't get done.
Rabaul? Ambon? Timor?
All important, but not as important as Sumatra, because that is where the oil is, and Malaya, because that needs to be taken to get the oil.

This is a major problem for the Japanese.
A raid doesn't do it if the allies back off until the Kido Butai goes away, which they would have to do after a week or two.
And putting the Kido Butai in an area that has enemy submarines and torpedo bombers for more than a day or two is a bit risky, even for the Japanese.
Losing a carrier or two would be a catastrophe for the IJN. Midway in the Java sea ends any possibility of victory.

 

[Antiochus V]

So the more I ponder this, the more I feel the British and Dutch have to weather a storm, namely the Kido Butai. How far south might they come. In the suggested timeline the RAF have a working early warning system with Radar, giving their Hurricanes and Buffalos time to get airborne and affect a good intercept off shore. There would be very few bomber assets, but a steady flow coming as was historically. The obvious comparator is the Ceylon raids.

And the KB would have to be doing this without a IJA invasion force being available, so this does in effect become a raid.

The trouble with using the KB was that it had a small pool of replacement pilots and a low level of spare aircraft. It started at its peak level of effectiveness both in relative and absolute terms (there was both a small training system and a likely upcoming fuel shortage). Thus every time it saw use it became a bit less effective as it suffered a few more pilot losses. At the same time the Allied carrier and regular air force was ramping up and bringing in new designs of aircraft in increasing quantities.

I think the KB could have been used to cover landings raid, but the attritional losses would have been a concern for the Japanese fleet. My suspicion is they would have preferred to rely on capturing airfields and minimising risk in advance of the expected great battle with the US fleet. That said the KB could probably carry out several raids on key ports and in the process catch a few allied warships and cargo vessels at an acceptable cost. A few Dutch ports and Darwin would be the likely the targets, presumably the destruction of shipping and repair yards would be the goals.

Worth bearing in mind that for the Allies it is often better to fight air battles over land, as the pilots can be recovered. Related to your Radar the Japanese lack of radar would make them vulnerable to unexpected air attacks, forcing them to keep a larger than necessary CAP in the air at all times, which in turn means more wear and tear losses.

 

[Fatboy Coxy]

When the Japanese centrifugal offensive was first discussed, it offered several different main axis of advance. One was Thailand, Malaya, Sumatra, Java and the back up to the Philippines, which was the Army's preference, another was in the opposite direction, starting with the Philippines which was the Navy's preference and a third was both arms together, which was the compromise. But there wasn't a straight up the middle, Borneo and then Java, as this left both flanks exposed strategically.

In this TL with the Japanese stalled in Malaya as well as the Philippines, the Japanese are being tested on how quickly they can redeploy and resupply their troops in both the Philippines and Malaya, which is very much an Army problem, excepting the convoying of transports. Which puts the Navy in a difficult situation. Going south (W Allies) as opposed to north (Russia) was the Navy preference, with the burning need for Oil. So do they, IJN assist the IJA in the land campaigns more directly, and if so how?

 

[Zheng He]

From December to June the Kido Butai was busy in OTL, so if they go south ITTL something else doesn't get done.
Rabaul? Ambon? Timor?

Using the KB was overkill for those operations. Fuchida described them as using a hammer to crack eggs.

 

[Cryhavoc101]

The trouble with using the KB was that it had a small pool of replacement pilots and a low level of spare aircraft. It started at its peak level of effectiveness both in relative and absolute terms (there was both a small training system and a likely upcoming fuel shortage). Thus every time it saw use it became a bit less effective as it suffered a few more pilot losses. At the same time the Allied carrier and regular air force was ramping up and bringing in new designs of aircraft in increasing quantities.

I think the KB could have been used to cover landings raid, but the attritional losses would have been a concern for the Japanese fleet. My suspicion is they would have preferred to rely on capturing airfields and minimising risk in advance of the expected great battle with the US fleet. That said the KB could probably carry out several raids on key ports and in the process catch a few allied warships and cargo vessels at an acceptable cost. A few Dutch ports and Darwin would be the likely the targets, presumably the destruction of shipping and repair yards would be the goals.

Worth bearing in mind that for the Allies it is often better to fight air battles over land, as the pilots can be recovered. Related to your Radar the Japanese lack of radar would make them vulnerable to unexpected air attacks, forcing them to keep a larger than necessary CAP in the air at all times, which in turn means more wear and tear losses.

I seem to recall that there was a pool of about 4000 trained pilots by Nov 41 - that is pilots that had gone through the 4 year training course - not all of these were the same level as the Elite pilots of the 1st and 2nd Carrier Division - and most of these would be ground down through attrition flying land based missions from 42 - 44 after the loss of the Carriers - relatively few pilots from the carriers were lost in the battles out of the 1500 odd Carrier qualified pilots although many would of course be lost to non combat causes.

The problem is it took 4 years to train one of them to that standard.

The main loss to the IJNs Naval Aviation in 1942 was the loss of skilled 'ground crews' many of whom where lost with the destroyed Carriers

 

[Fatboy Coxy]

I was looking at possible Japanese use of rail as a means of supply, reducing the merchant shipping requirements, and you can only supply Thailand/Malaya by ship, there is no interconnecting rail. However there seems to be a rail line along the length of Vietnam, does anyone know how good that was in 1942?. I'm thinking they could draw some resources from French Indo-China, rail to Saigon, and then convoy to Bangkok.

Which leads me to the next point, does anyone know the port capabilities of Saigon and Bangkok in the early 1940's?