Problem with that is that you leave Java (the lynchpin of the colony) open to a coup de main. A Japanese invasion force covered by aircraft carriers could push its way through Makassar Strait to land on - now undefended - Java.
It is absolutely a gamble but for the Japanese to launch that assault would mean passing multiple choke points and being in range of land based air. They tended to launch their operations leap frogging from area where they could establish airbases to the next target the could establish airbase. It also would mean that the Japanese would have a way to get intel on Dutch movements which would be difficult after the war starts for Java unless they have agents with radios and even then radios have a limited range so would have to either report to submarines or long range aircraft that would have to loiter at certain times in order to get the reports. As I said its a gamble but better a gamble than to be defeated in detail at each exterior base till the Japanese are at your door and establish bases.
 
On other point about Kenney, was from my reading, Hap Arnold gave Kenney far more operational control. MacArthur could choose strategic goals, but for the most part Kennedy handled his own Operational and Tactical missions. This was IMO a result of Mac Arthur and Brenton screwing the pooch in the Philippines and DEI.
I believe that it was in American Caesar written by William Manchester. GEN Kenney had a confrontation with GEN Sutherland over bombing missions. GEN Sutherland had LBJ-like ordered up a bombing mission. GEN Kenney disapproved and called GEN Sutherland on it. The CoS tried to pull rank on the Air Corp general. GEN Kenney calmly took a blank sheet of paper and embellished it with a dot. Then he drew a large circle around the dot. GEN Kenney then said, " The dot is what you know about airpower. The circle is what I know about airpower. If you wish, we can take it up with GEN MacArthur." It ended any future debate, then and there.
 
MWI 41112213 The Canadians Take A Step Forward

Fatboy Coxy

Monthly Donor
1941, Saturday 22 November;

HMCS Prince Henry had arrived mid-morning, and had immediately been given a berth on the north wall of the Naval Dockyard. A very disgruntled looking Insect class river gunboat, HMS Scarab was anchored in the straits, having given up the berth, the servicing of her six-inch guns, interrupted. On board the ex-Canadian National Railway ocean liner come auxiliary cruiser was the 8th RCAF Airfield Construction Company, joining the 3rd RCAF and 1st New Zealand units, which had arrived late spring. Again, most of the heavy equipment they would use had already been shipped here, the rest was due to arrive before the end of the month.

Forty or so of the passengers were not construction men, ten were for the RCSC signals company, a few were RCAF radar technicians, four were volunteer officers for the Indian Army and the rest were ground and aircrew for the Canadian Article XV squadrons. A number of cars and trucks awaited these men, and once ashore, they were whisked away, their units pleased to see them. The Airfield Construction Company was marched down to a naval barracks and distracted with tea and cake, while they awaited their transport to a holding camp on Singapore Island. On Monday they would embark on a train taking them up to Taiping, where reunited with their equipment, they would begin work on developing or creating new airfields in Northern Malaya.

The first to alight off the ship however, was its captain, Capt Ronald Ian Agnew, RCN, looking totally bemused and concerned about the summons he had just received. Waiting on the dockside for him was a smartly dressed Sub-Lieutenant along with Admiral Layton’s own Humber staff car and driver. Quickly they were driven away, while the Prince Henry’s First Lieutenant took over the ship’s duties.

The naval offices were a hive of activity, but the Sub-Lieutenant expertly led Agnew through the seemingly chaotic building, down corridors, upstairs, through doors, until they found themselves outside Layton’s office. The Aide turned to Agnew and said, I’ll take my leave here sir, but I’ll take you back when the Admiral has finished with you, threw a smart salute, and turned back down the corridor, just as the Royal Marine sentry opened the door, and gestured Agnew in with his white gloved hand, closing the door behind him.

“Ah Captain Agnew, Ronald I believe, welcome, I trust your voyage went well”, Layton crossed the room, and shook his hand. “Do take a seat old boy, I generally take a coffee this time of the morning, care to join me, yes” He rang a small silver bell, and a smart steward appeared from a side door. “Two coffees please Malone” the steward nodded and disappeared again. “Well, I expect your wondering whats going on Ronald, you don’t mind me calling you Ronald do you, no, that’s OK then. And while in this room please do refer to me as Geoffrey.

Now let’s see, following representations to the Admiralty, for an idea I have, they have kindly agreed to transfer you and your ship to my command for an indeterminable time in the future. War with Japan may well happen before Christmas, and a number of contingency plans are being made, and thanks to an agreement with the Royal Canadian Navy, along with the ship blueprints and some small alterations to the ship, your now included in one of them.

As I understand it, your ship has a capability to carry 300 troops on a long voyage, and could carry 450 on a short one, you have a main armament of four 6-inch guns, two 3-inch guns for air defence, and can do 20 plus knots when asked, yes so?”. Agnew was about to answer when the side door opened, and so just nodded. Malone, a small middle-aged Irishman, his thinning hair slick with hair cream, in his crisp white jacket and trousers, brought in a tray with a coffee pot, two china cups in their saucers, a small jug of cold milk, a bowl of brown sugar, and a plate of shortcake biscuits, all in the same matching decorative china. “That will be all Malone” Layton picked up the coffee pot, “shall I be mum, milk, sugar?”

“No milk please, er, Geoffrey, one sugar, would be lovely”

“Ah you North Americans, I can’t get use to no milk in my coffee, indeed the milkier the better for me. Now, where was I, oh yes, well it seems we might have a little job for you and your ship, something a bit more interesting than criss-crossing the Pacific every ten weeks. Sorry, I didn’t ask, biscuit….”

When Agnew was dropped off dockside of his ship over three hours later, he found all his passengers had disembarked and left, but an elderly lieutenant from the Dockyard was up on his bridge with his First Lieutenant, and his ship was already missing one of its ship’s boats, with a number of dockyard hands swarming around the davits with some urgency. Clearly, despite the very pleasant hour with Layton, the brief twenty minutes with his Chief of Staff, and the next hour and a half with a Captain Atkinson, Deputy Superintendent of the Dockyard, the prioritised activity on his ship told him Layton was also a man of action. That fact had been driven home earlier, when a staff officer had told him there was a flight leaving for Penang first thing tomorrow, with a seat reserved for him, and an expectant Commodore Abbott waiting.
 
Problem with that is that you leave Java (the lynchpin of the colony) open to a coup de main. A Japanese invasion force covered by aircraft carriers could push its way through Makassar Strait to land on - now undefended - Java.
The Makassar Strait is not a conducive place to conduct carrier flight ops. I doubt that the IJN would entertain operating them there. I suspect that the ops would more likely occur while in the Celebes Sea.

There are currents which although you are making turns for thirty (30) kts will substantially reduce your forward speed. There will be the tidal forces affecting your movement. If the wind direction changes, you may no longer be able to launch or recover aircraft, as you have run out of sea to operate in. If Malaya has entered the Monsoon Season, does this also affect the Borneo Celebes region? I can see fouled decks and man overboard situations. And this is before mentioning submarines. Large target displacing 20,000 to 40,000 tons. Steady course and speed for long durations. Lot's of firing solutions on a starboard AOB 30-45-90-135 degrees. It's tricky. It's not going to be like a night surface action off Balikpapan.

There is always the potential that the B-17's can now get lucky. They are closer and perhaps able to make a couple of daily raids. Maybe a strike is ready to go awaiting launch. The B-17's appear in cloud breaks and it's a prequel to Midway. Yikes! If you lose CV(s) to sinking, heavy bomb damage or hull plate displacement, the best prospect is it's off to the yards in Japan. If you CAN get there.

The effect that this has will make the raids on Darwin, the IO, Port Moresby or Midway become IJN pipe dreams. I can only guess how much rancor can be generated towards the IJA, especially if they are bogged down in Malaya and the PI simultaneously. The "Heroes of Pearl Harbor" resting in Davy Jones Locker @ Lat 3 deg , 18 min S Long 118 deg , 34 min E. Not a good image.
 
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I believe that it was in American Caesar written by William Manchester. GEN Kenney had a confrontation with GEN Sutherland over bombing missions. GEN Sutherland had LBJ-like ordered up a bombing mission. GEN Kenney disapproved and called GEN Sutherland on it. The CoS tried to pull rank on the Air Corp general. GEN Kenney calmly took a blank sheet of paper and embellished it with a dot. Then he drew a large circle around the dot. GEN Kenney then said, " The dot is what you know about airpower. The circle is what I know about airpower. If you wish, we can take it up with GEN MacArthur." It ended any future debate, then and there.
And the ability to go to MacArthur, lay in Kenney's ability to then go directly to Hap Arnold.
 
The Makassar Strait is not a conducive place to conduct carrier flight ops. I doubt that the IJN would entertain operating them there. I suspect that the ops would more likely occur while in the Celebes Sea.

There are currents which although you are making turns for thirty (30) kts will substantially reduce your forward speed. There will be the tidal forces affecting your movement. If the wind direction changes, you may no longer be able to launch or recover aircraft, as you have run out of sea to operate in. If Malaya has entered the Monsoon Season, does this also affect the Borneo Celebes region? I can see fouled decks and man overboard situations. And this is before mentioning submarines. Large target displacing 20,000 to 40,000 tons. Steady course and speed for long durations. Lot's of firing solutions on a starboard AOB 30-45-90-135 degrees. It's tricky. It's not going to be like a night surface action off Balikpapan.

There is always the potential that the B-17's can now get lucky. They are closer and perhaps able to make a couple of daily raids. Maybe a strike is ready to go awaiting launch. The B-17's appear in cloud breaks and it's a prequel to Midway. Yikes! If you lose CV(s) to sinking, heavy bomb damage or hull plate displacement, the best prospect is it's off to the yards in Japan. If you CAN get there.

The effect that this has will make the raids on Darwin, the IO, Port Moresby or Midway become IJN pipe dreams. I can only guess how much rancor can be generated towards the IJA, especially if they are bogged down in Malaya and the PI simultaneously. The "Heroes of Pearl Harbor" resting in Davy Jones Locker @ Lat 3 deg , 18 min S Long 118 deg , 34 min E. Not a good image.
To say nothing about narrow waters, close enough for Dutch subs, with torpedoes that function quite well, as well as Hart's surviving S-Boats with functional MK VIIIs.
 
General Kenney also had the advantage of having his own communication net, both voice and teletype, and did not have to go through Mac's HQ to send and receive messages form higher command and DC.
 
It is absolutely a gamble but for the Japanese to launch that assault would mean passing multiple choke points and being in range of land based air. They tended to launch their operations leap frogging from area where they could establish airbases to the next target the could establish airbase. It also would mean that the Japanese would have a way to get intel on Dutch movements which would be difficult after the war starts for Java unless they have agents with radios and even then radios have a limited range so would have to either report to submarines or long range aircraft that would have to loiter at certain times in order to get the reports. As I said its a gamble but better a gamble than to be defeated in detail at each exterior base till the Japanese are at your door and establish bases.
I don't know if any Allied commander in the east was as daring or imaginative as this to entertain such a bold gamble in early 1942.
 
I don't know if any Allied commander in the east was as daring or imaginative as this to entertain such a bold gamble in early 1942.
The USAFFE was led by a Brigade Commander in the Great War, who oversaw the reduction of his Army. The Malaya
Campaign was directed by a Brigade Commander in the Great War who became a serviceable staff officer. The Dutch
Commander did not participate in the Great War.

Based on their limited experience in modern warfare, it does not appear than there was much absorption and application
of what was happening in the first two years of World War II. The American and Dutch ground commanders were out
of the loop, so to speak in PI and NEI. The British ground commander saw the war unfold from a nearer perspective.

I suspect that there may have been better OTL leadership choices that could have been made for Malaya and the PI. The problem
is that both the British and American leaders saw themselves as being military matter experts. Particularly in Naval issues.
Perhaps no longer having a home country and a government in exile led the Dutch to clearer thinking?

I agree that where imagination and risk are required, there is a severe shortage in the East. Still it's nice to wonder about
it playing out on a table top. Did the British and Dutch ever meet to run through scenarios and possible outcomes?
 
I don't see the reasoning of forcing Kido Butai through the Makassar Straits. Off Tanjung Ongkona there is little room to manuever. Once you reach the Makassar area you have another cluster of atolls, islands and reefs heading to Borneo. The Arafura and Timor Sea are somewhat better areas for carrier ops, even though they are shallow so to speak.
Like the Borneo shelf, but less cluttered.
It is absolutely a gamble but for the Japanese to launch that assault would mean passing multiple choke points and being in range of land based air. They tended to launch their operations leap frogging from area where they could establish airbases to the next target the could establish airbase. It also would mean that the Japanese would have a way to get intel on Dutch movements which would be difficult after the war starts for Java unless they have agents with radios and even then radios have a limited range so would have to either report to submarines or long range aircraft that would have to loiter at certain times in order to get the reports. As I said its a gamble but better a gamble than to be defeated in detail at each exterior base till the Japanese are at your door and establish bases.
The Makassar Strait is not a conducive place to conduct carrier flight ops. I doubt that the IJN would entertain operating them there. I suspect that the ops would more likely occur while in the Celebes Sea.
I don't know if any Allied commander in the east was as daring or imaginative as this to entertain such a bold gamble in early 1942.
I can agree that the coup de main scenario is extremely unlikely, in hindsight . We know that the Japanese Empire wants land based aircover for their invasion forces and we know that Japan never really considered only attacking the Dutch East Indies without a declaration of war against the United States and Kingdom. Alas, the Dutch East Indies government did not know those things and thus couldn't - and certainly wouldn't - take the risk.
 
Based on their limited experience in modern warfare, it does not appear than there was much absorption and application
of what was happening in the first two years of World War II. The American and Dutch ground commanders were out
of the loop, so to speak in PI and NEI.
Well, one thing that the you can say about the KNIL is that they weren't backward thinking in matters of doctrine. The invasion of Poland prompted them to start a reorganization to get a Blitzkrieg capable fight force. One that wasn't ready by the time the Japanese came knocking but still.
The problem
is that both the British and American leaders saw themselves as being military matter experts. Particularly in Naval issues.
I can't speak for the KNIL in that matter but Helfrich & Co certainly considered the British and - to a lesser extend - the Americans to be absolute knobs about fighting a war in the archipelago without capital ships. Considering the performance of the Dutch surface assets during the war this was - almost - complete bonkers.
 
1941, Saturday 22 November;

HMCS Prince Henry had arrived mid-morning, and had immediately been given a berth on the north wall of the Naval Dockyard. A very disgruntled looking Insect class river gunboat, HMS Scarab was anchored in the straits, having given up the berth, the servicing of her six-inch guns, interrupted. On board the ex-Canadian National Railway ocean liner come auxiliary cruiser was the 8th RCAF Airfield Construction Company, joining the 3rd RCAF and 1st New Zealand units, which had arrived late spring. Again, most of the heavy equipment they would use had already been shipped here, the rest was due to arrive before the end of the month.

Forty or so of the passengers were not construction men, ten were for the RCSC signals company, a few were RCAF radar technicians, four were volunteer officers for the Indian Army and the rest were ground and aircrew for the Canadian Article XV squadrons. A number of cars and trucks awaited these men, and once ashore, they were whisked away, their units pleased to see them. The Airfield Construction Company was marched down to a naval barracks and distracted with tea and cake, while they awaited their transport to a holding camp on Singapore Island. On Monday they would embark on a train taking them up to Taiping, where reunited with their equipment, they would begin work on developing or creating new airfields in Northern Malaya.

The first to alight off the ship however, was its captain, Capt Ronald Ian Agnew, RCN, looking totally bemused and concerned about the summons he had just received. Waiting on the dockside for him was a smartly dressed Sub-Lieutenant along with Admiral Layton’s own Humber staff car and driver. Quickly they were driven away, while the Prince Henry’s First Lieutenant took over the ship’s duties.

The naval offices were a hive of activity, but the Sub-Lieutenant expertly led Agnew through the seemingly chaotic building, down corridors, upstairs, through doors, until they found themselves outside Layton’s office. The Aide turned to Agnew and said, I’ll take my leave here sir, but I’ll take you back when the Admiral has finished with you, threw a smart salute, and turned back down the corridor, just as the Royal Marine sentry opened the door, and gestured Agnew in with his white gloved hand, closing the door behind him.

“Ah Captain Agnew, Ronald I believe, welcome, I trust your voyage went well”, Layton crossed the room, and shook his hand. “Do take a seat old boy, I generally take a coffee this time of the morning, care to join me, yes” He rang a small silver bell, and a smart steward appeared from a side door. “Two coffees please Malone” the steward nodded and disappeared again. “Well, I expect your wondering whats going on Ronald, you don’t mind me calling you Ronald do you, no, that’s OK then. And while in this room please do refer to me as Geoffrey.

Now let’s see, following representations to the Admiralty, for an idea I have, they have kindly agreed to transfer you and your ship to my command for an indeterminable time in the future. War with Japan may well happen before Christmas, and a number of contingency plans are being made, and thanks to an agreement with the Royal Canadian Navy, along with the ship blueprints and some small alterations to the ship, your now included in one of them.

As I understand it, your ship has a capability to carry 300 troops on a long voyage, and could carry 450 on a short one, you have a main armament of four 6-inch guns, two 3-inch guns for air defence, and can do 20 plus knots when asked, yes so?”. Agnew was about to answer when the side door opened, and so just nodded. Malone, a small middle-aged Irishman, his thinning hair slick with hair cream, in his crisp white jacket and trousers, brought in a tray with a coffee pot, two china cups in their saucers, a small jug of cold milk, a bowl of brown sugar, and a plate of shortcake biscuits, all in the same matching decorative china. “That will be all Malone” Layton picked up the coffee pot, “shall I be mum, milk, sugar?”

“No milk please, er, Geoffrey, one sugar, would be lovely”

“Ah you North Americans, I can’t get use to no milk in my coffee, indeed the milkier the better for me. Now, where was I, oh yes, well it seems we might have a little job for you and your ship, something a bit more interesting than criss-crossing the Pacific every ten weeks. Sorry, I didn’t ask, biscuit….”

When Agnew was dropped off dockside of his ship over three hours later, he found all his passengers had disembarked and left, but an elderly lieutenant from the Dockyard was up on his bridge with his First Lieutenant, and his ship was already missing one of its ship’s boats, with a number of dockyard hands swarming around the davits with some urgency. Clearly, despite the very pleasant hour with Layton, the brief twenty minutes with his Chief of Staff, and the next hour and a half with a Captain Atkinson, Deputy Superintendent of the Dockyard, the prioritised activity on his ship told him Layton was also a man of action. That fact had been driven home earlier, when a staff officer had told him there was a flight leaving for Penang first thing tomorrow, with a seat reserved for him, and an expectant Commodore Abbott waiting.
Lovely written chapter, that upperclass British Layton "call me Geofry'' with it's distinquished upperclass self confidence, absolute briliant.
''Shall I be mum, milk sugar'' 😄
....and just two weeks to go....
 
Any consideration to reassigning the Makassar Garrison to reinforce the KNIL garrison at Manado? How quickly can the KNIL build a rough airfield at Manado? The ability to position a squadron with refueling and rearming capabilities perhaps?
There was already an well equiped airfield/airbase near Manado, Mapanget and Tonado lake was a air base for the Navy flyboats.
The KNIIL was already organising the defense with special attention to an airborne attack. and naval landings at Kema
I mention this as Manado may be the key to the ABDA defense. Say the IJN Naval Landing Forces and Naval paratroopers are met by a reinforced opposed landing force and fail to secure the northeastern tip of Celebes Island. Then it will take at least a month to try again. Maybe even longer. The follow on Battle of Balikpapan, does not occur two weeks later near the end of January 1942. The Makassar Strait does not turn into dominoes.
Manado was certainly important but the most strategic important city on Celebes was the more Southern Kendari, with had two well equiped KNIL airbases. Most imortant this airbase was in the range of Darwin Austrailia.

Constructed in 1938, Kendari II Airfield, which was located 27 km from the eponymous city, increased the military significance of the Southeast Celebes Region exponentially. Upon its completion, Kendari II was considered as the best airfield throughout the Dutch East Indies, if not the entire Southeast Asia. The airfield had three runways and additional space for expansion. Before the outbreak of war, Dutch forces had already built barracks that can accommodate 500 troops and planned to expand it more for Australian or KNIL reinforcements.
To bolster its defense, four KNIL brigades (15-18 troops each) garrisoned the airfield, before they were reinforced by additional troops, AA guns, machine guns and mortars from Java. By the end of 1941, Dutch forces strength on the city numbered around 500 troops, of which 320 of them are regular soldiers. By 1942, about 3,000 bombs and a million liters of aircraft fuel had been placed on Kendari II to accommodate American bombers who were using the airfield as a staging base to refuel and rearm in their operations against the southern Philippines.

You are correct the regarding the number of men assigned to defend these place. It could be more, and perhaps more troops could be stationed in the cities in the North who were more important than the Southern Makassar. The largest problem of the KNIL was their low numbers. an other thing which weakened the KNIL, as I understood was the re-organisation which was still ongoiing and as I understood caused unrest among the multi ethnic Indonesian troops.

Below some photographs of KNIL soldiers. Note the use of the klewangs/sabre
1696663253329.jpeg

1696663155669.jpeg


I now te whole thing is a too detailed side road of this time line
 

Fatboy Coxy

Monthly Donor
The Makassar Strait is not a conducive place to conduct carrier flight ops. I doubt that the IJN would entertain operating them there. I suspect that the ops would more likely occur while in the Celebes Sea.

There are currents which although you are making turns for thirty (30) kts will substantially reduce your forward speed. There will be the tidal forces affecting your movement. If the wind direction changes, you may no longer be able to launch or recover aircraft, as you have run out of sea to operate in. If Malaya has entered the Monsoon Season, does this also affect the Borneo Celebes region? I can see fouled decks and man overboard situations. And this is before mentioning submarines. Large target displacing 20,000 to 40,000 tons. Steady course and speed for long durations. Lot's of firing solutions on a starboard AOB 30-45-90-135 degrees. It's tricky. It's not going to be like a night surface action off Balikpapan.

There is always the potential that the B-17's can now get lucky. They are closer and perhaps able to make a couple of daily raids. Maybe a strike is ready to go awaiting launch. The B-17's appear in cloud breaks and it's a prequel to Midway. Yikes! If you lose CV(s) to sinking, heavy bomb damage or hull plate displacement, the best prospect is it's off to the yards in Japan. If you CAN get there.

The effect that this has will make the raids on Darwin, the IO, Port Moresby or Midway become IJN pipe dreams. I can only guess how much rancor can be generated towards the IJA, especially if they are bogged down in Malaya and the PI simultaneously. The "Heroes of Pearl Harbor" resting in Davy Jones Locker @ Lat 3 deg , 18 min S Long 118 deg , 34 min E. Not a good image.
Hi Nevarinemex, I'm, with you on this one, the Kido Butai would only pass through the Makassar Straits after both Borneo and Celebes have been fully occupied, but I'm not sure why they have to come into the fight yet, if at all.
 

Fatboy Coxy

Monthly Donor
There was already an well equiped airfield/airbase near Manado, Mapanget and Tonado lake was a air base for the Navy flyboats.
The KNIIL was already organising the defense with special attention to an airborne attack. and naval landings at Kema

Manado was certainly important but the most strategic important city on Celebes was the more Southern Kendari, with had two well equiped KNIL airbases. Most imortant this airbase was in the range of Darwin Austrailia.

Constructed in 1938, Kendari II Airfield, which was located 27 km from the eponymous city, increased the military significance of the Southeast Celebes Region exponentially. Upon its completion, Kendari II was considered as the best airfield throughout the Dutch East Indies, if not the entire Southeast Asia. The airfield had three runways and additional space for expansion. Before the outbreak of war, Dutch forces had already built barracks that can accommodate 500 troops and planned to expand it more for Australian or KNIL reinforcements.
To bolster its defense, four KNIL brigades (15-18 troops each) garrisoned the airfield, before they were reinforced by additional troops, AA guns, machine guns and mortars from Java. By the end of 1941, Dutch forces strength on the city numbered around 500 troops, of which 320 of them are regular soldiers. By 1942, about 3,000 bombs and a million liters of aircraft fuel had been placed on Kendari II to accommodate American bombers who were using the airfield as a staging base to refuel and rearm in their operations against the southern Philippines.

You are correct the regarding the number of men assigned to defend these place. It could be more, and perhaps more troops could be stationed in the cities in the North who were more important than the Southern Makassar. The largest problem of the KNIL was their low numbers. an other thing which weakened the KNIL, as I understood was the re-organisation which was still ongoiing and as I understood caused unrest among the multi ethnic Indonesian troops.

Below some photographs of KNIL soldiers. Note the use of the klewangs/sabre
View attachment 860501
View attachment 860500

I now te whole thing is a too detailed side road of this time line
Hi Parma, love this detail, do you have any more please.
 
It is absolutely a gamble but for the Japanese to launch that assault would mean passing multiple choke points and being in range of land based air. They tended to launch their operations leap frogging from area where they could establish airbases to the next target the could establish airbase. It also would mean that the Japanese would have a way to get intel on Dutch movements which would be difficult after the war starts for Java unless they have agents with radios and even then radios have a limited range so would have to either report to submarines or long range aircraft that would have to loiter at certain times in order to get the reports. As I said its a gamble but better a gamble than to be defeated in detail at each exterior base till the Japanese are at your door and establish bases.
Short wave radios have very good ranges. An agent with a decent SWR could broadcast thousands of miles.
 
Short wave radios have very good ranges. An agent with a decent SWR could broadcast thousands of miles.
Yes, but. Shortwave is affected in hard-to-understand ways by environmental and atmospheric factors, and even geology. A sender has no way to know for certain if their sent-once message will have reached a particular distant listener. Reliable shortwave communication involves sending repeatedly, at different times of day, preferably from multiple transmitting antennas; and the other end having many listening stations at distributed locations with complex antenna arrays, all noting what they've received and collating a combined transcript.

Shortwave antennas must be raised above their surroundings (vegetative, buildings and the terrain) to have much range. Historically one of the hardest aspects of operating a clandestine shortwave system has been concealing the antenna. A "20 meter band" vertical array needs a radiator of about six and a half meters, and multiple other elements. A horizontal dipole's main element is about ten meters long, and...ideally...raised above its surroundings by twenty meters or so.

A favorite competitive shortwave hobbyist activity is DXing...listening for, and keeping records of, distant senders you've heard. If there was more consistency to shortwave as a communications method, shortwave reception would be a simple matter of power, antenna configuration and a few other factors...but it's not so simple.
 
Yes, but. Shortwave is affected in hard-to-understand ways by environmental and atmospheric factors, and even geology. A sender has no way to know for certain if their sent-once message will have reached a particular distant listener. Reliable shortwave communication involves sending repeatedly, at different times of day, preferably from multiple transmitting antennas; and the other end having many listening stations at distributed locations with complex antenna arrays, all noting what they've received and collating a combined transcript.

Shortwave antennas must be raised above their surroundings (vegetative, buildings and the terrain) to have much range. Historically one of the hardest aspects of operating a clandestine shortwave system has been concealing the antenna. A "20 meter band" vertical array needs a radiator of about six and a half meters, and multiple other elements. A horizontal dipole's main element is about ten meters long, and...ideally...raised above its surroundings by twenty meters or so.

A favorite competitive shortwave hobbyist activity is DXing...listening for, and keeping records of, distant senders you've heard. If there was more consistency to shortwave as a communications method, shortwave reception would be a simple matter of power, antenna configuration and a few other factors...but it's not so simple.
For a short range radio to reach Indochina, or a Japanese sub, it has to have sufficient power. That level of power could be picked up by the USN intercept arrays on Sangley Point or Corrigidor, in the Philippines. Those arrays could pick huge amounts of Japanese radio traffic. Not necessarily read the traffic, but tell that someone is transmitting in Japanese code from Java.
 
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