Kanmon Undersea Railway Tunnel & the Invasion of Japan

Discussions on all aspects of the Japanese Empire, from the capture of Taiwan until the end of the Second World War.
Mil-tech Bard
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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 19 Feb 2013 18:51

The electric locomotive used in the Kanmon Undersea Railway Tunnel (KURT) during Would War 2 was the EF 10 35 engine.

The classification means --
o "E" for "electric"
o "F" for six driving axles
o "10" for "maximum speed under 85 km/h"
o "35" for "AC/DC locomotive"

Locomotive Classification Source --

http://www.japaneserailwaysociety.com/j ... /class.htm

This locomotive was an electric freight hauler that cycled through the 3.6 km KURT line from one marshaling yard to the other, moving rolling stock and Steam Locomotives from Honshu to Kyushu and back.

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 19 Feb 2013 19:51

This is what the official summary report in the attacks on Japanese transportation said (See below), however, please remember the foot notes from other USSBS reports earlier in this thread and bear in mind the fact that the 20th Air Force never requested Azon bombs.

The 20th Air Force transportation campaign was to be built around radar bombing with the X-band AN/APQ-7 Eagle bombing radar.

The USAAF Air Technical Service Command (ATSC) documents I have read stated that there were experimental shipments of VB-1 Azon and VB-3 Razon (500 bomb guidance units each) for a small number of B-24 Liberator and B-32 Dominator bombers in the 5th Air Force at war's end. The stock of 500 VB-3 were on Okinawa in 1950 for the War in Korea. The VB-1's had been scraped.

Deeply consider the bold-italic-underline sections below given those facts.

The War against Japanese Transportation 1941-1945 (1947)
United States Strategic Bombing Survey
Volume no. 54
Page 6

http://archive.org/details/waragainstjapane54unit
Japan still had, however, a functioning railroad
system which was physically intact. Undermaintenance
had set in, to be sure, but it
had not yet affected the smooth operation of the
system and had caused little decline in its peak
capacity. The few scattered attacks upon rail
facilities and the great raids upon the cities
had been mere pinpricks as far as the railroad
system was concerned. A few traffic interruptions
of very temporary duration had occurred.
Line and yard capacity was essentially
unimpaired. Only the loading, unloading, and
collection and delivery systems in some of the
cities subjected to the great fire raids had been
disrupted. But in those locations the need for
such facilities had contemporaneously declined
as traffic demands fell with the burning of industrial
and commercial plant and the exodus
of population. The railroads were still capable
of serving. Even the atom bomb attacks had but
temporary and minor effects upon railroad facilities
and service. Only the carrier strike
against the ferries from Hokkaido was a sig
nificant blow against the railroad system as a
functioning unit.
Interdiction of the railroad
system, had it been undertaken, would have deprived
Japan of all significant transportation
and left the nation industrially and militarily
almost completely immobile.
Page 8
Failure to attack the railroad system as soon
Page 10
as the force was available resulted in the loss
of a major opportunity. With her shipping so
seriously reduced, Japan depended almost entirely
upon her railroad system for transportation.

The disposition and supply of her forces
to resist invasion must rely upon the railroads
the remaining industry must rely almost wholly
upon Japanese sources of fuel and raw material
which could be transported only by rail ; and the
distribution of food and elementary necessities
of life could not be accomplished without the
rails. The Japanese railroad system was, moreover,
one of the most vulnerable of any size to
be found anywhere. With its through movement
confined almost entirely to the two main lines
the length of Honshu, and the supply of bulk
traffic to these lines bottlenecked at the Kanmon
tunnel on the south and the Hakodate and
Aomori ferries in the north, opportunities for
diversion and rerouting were almost nil
. Moreover
the bulk of the traffic had become longhaul
with the virtual demise of coastwise shipping
and traffic must use one or another of these
main lines for a substantial portion of their
length. Any serious interruption of either line
and especially of the high capacity Sanyo line,
west of Kobe, would have seriously reduced the
major flow of traffic from Kyushu northeast to
the industrial cities and the loss of both lines
would have paralyzed the flow. The less important
movement southwest from the northern tip
of Honshu could have been similarly paralyzed
by the cutting of both lines, for it was largely
through business. The main line between Tokyo
and the Kanmon was particularly open to attack
because at many points it hugged the coast
and its approximate location could be picked up
by radar by reference to coastal features even
under conditions of low visibility
.
All lines had
many structures, such as bridges, tunnels, cuts,
fills, and retaining walls which would have been
desirable targets for carrier-borne dive bombers
or similar aircraft under visual conditions. The
Kanmon tunnels themselves, keys to the most
important coal and steel movement, were most
vulnerable. They were easy to pick up by radar
and required only destruction of tunnel mouths
and approaches for eff'ective neutralization.
The
Honshu rail system, although it used some lowgrade
Honshu coal, could not be fully worked
without considerable quantities of Kyushu and
Hokkaido coal.


A program, therefore, involving the successful
destruction of the Kanmon and the contemporary
destruction of the rail ferries from
Hokkaido (as was actually done quite effectively
by a carrier task force at a late date)
followed by half a dozen well-chosen line cuts
on the main routes would have disposed effectively
of the Japanese rail system as an economic
asset. The system had only extremely
limited recuperative powers. Neither plans nor
materials were in hand for replacing any major
structures. Not even bridge timber had been
assembled as a precaution against such attack.
And the material required could not be obtained
from the mills except after considerable lapse
of time. The objective of the program would be
to stop the flow over the main routes. Its accomplishment
would require very little physical
destruction. Recuperation need not worry the
attacker, for no quick reaction was possible.
Had it begun, however, force was at hand to
bring it promptly to an end.

It appears that force was at hand within
range of the desirable targets by mid-April
1945. Reconnaissance could have been secured
during the previous months. One hundred dispatched
sorties by B-29s with 800 tons of Azon
bombs should have been sufficient for a complete
program of line cuts, including the approaches
to the Kanmon tunnel, designed to cut all significant
main rail routes. The program would
require also the cooperation of a carrier raid
against the Hokkaido ferries of similar magnitude
and effectiveness to the one actually employed,
but it would have been preferable to
accomplish it at an earlier date. Alternatively
this operation against Japanese rail lines could
have been accomplished with 650 B-29 sorties
carrying 5,200 tons of ordinary genei'al-purpose
bombs or 1,740 carrier-based sorties carrying
1,300 tons. A combination of the two types of
attack might prove to be the most efficient. A
similar or somewhat greater eff'ort monthly
might have been required to maintain the interdiction.

Figure 3 indicates a possible plan of
areas within which the necessary cuts might
have been spotted and the order of importance
of the several zones. It also spots the points included
in calculating these force requirements.

A table of force requirements (Figure 4) follows
the map.

Such a decimation of the rail system could
Page 11
have seriously impeded military dispositions essential
for defense against invasion. It could
have paralyzed all economic traffic by rail, not
only by cutting the main routes, but also by
depriving the separated segments of the coal
needed even for local operations. Even the low
quality fuel available on Honshu could not have
been distributed where needed, and stocks in
the hands of most divisions of the railroad were
sufficient for but a few days operation. The restoration
of the railroads would have become the
primary task of the day, but would have been
slow and confused because of the complete lack
of preparation to cope with such a situation.

Meanwhile Japan would have been paralyzed
and might have been ripe for surrender sooner
than was actually the case. It is difficult to realize
the profound and ramifying effects of a
nearly complete transportation tie-up. Such a
prolonged interruption of transport has not occurred
in the modern world. Judgment, therefore,
differs as to the significance of the effects
which would have been produced upon the people
and upon the government and the rapidity
with which such effects would have been felt.

Had an invasion still appeared necessary, and
had some local railroad operation been restored
for military purposes, the air foi'ces available
could have plastered the entire limited rail system
during the several weeks immediately before
the landings.
Page 69
The Kanmon Tunnel. — Prior to June 1942,
when the first single track tube of the Kanmon
tunnel was opened, primary reliance was placed
upon kihansen. These carried about 10 million
tons of the annual total 13.8 million tons. Kisen
accounted for 3.3 million tons and rail movements
over the now-abandoned Komorie-Shimonoseki
rail ferry for 400,000 tons. With the
opening of the Kanmon tunnel, coal shipments
by rail totalling 1.9 million tons in the fiscal
year 1942 and 4.4 million tons in the year 1943
were made possible. Between October 1943 and
June 1945, shipments were remarkably stable in
the range of 400,000 to 490,000 tons per month.
The total for 1944-45 was 5.5 million tons.
In October 1944 a second tube was opened. It
is a somewhat remarkable fact that the tonnage
of coal moved through the two tubes was
no greater than it had been previously through
the single tube. It seems clear that tunnel capacity
was not the limiting factor on coal movement
by rail, but rather that the capacity of the
mines had declined by the time the second tube
was completed.
Of the total Kyushu and Honshu
coal movement, the tunnel accounted for
the following percentages:
Percent
1941-42 3.2
1942-43 30.3
1943-44 45.5
1944-45 60.9

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 24 Feb 2013 15:09

Attached is another Joint Targeting Office map of Kanmon Undersea Railway Tunnel with additional highlighting to make clear the route of the tunnel.
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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 24 Feb 2013 16:42

The attached photo below is a map plate (plate 115 Reports of General Mac Arthur Vol 1) from General Mac Arthur's April 1945 plan to interdict Japanese transportation for Operation Olympic.

The plan resulted in an immediate 7 April 1945 communication from Washington D.C. AFIJT ( Air Force Intelligence Joint Targeting?) reserving the Kanmon Undersea Railway Tunnel for first Javaman and later the 20th Air Force.

This prevented any attacks on Kanmon Undersea Railway Tunnel whatsoever in World War II.

See note 135 in the text clip below:

http://www.ibiblio.org/hyperwar/AAF/V/A ... html#cn135


The Army Air Forces in WW2
The Pacific: Matterhorn to Nagasaki
June 1944 to August 1945
Chap 22
page 699


After the war USSBS concluded that FEAF might better have concentrated against rail targets, ten of which (five yards and five bridges) were vital to

--699--

both military and economic traffic between Honshu and Kyushu.133

In defense of FEAF, it must be noted that its air units were still feeling out Japanese resistance when the war unexpectedly ended. A systematic USASTAF-FEAF transportation assault had been planned, and the first USASTAF operation of the series took place on the last day of the war.134 It was recognized that the Kammon Tunnel between Kyushu and Honshu was the most important single transportation target in Japan,135 but the target was being saved until four disguised air rescue boats, remotely controlled and each loaded with 25 tons of high explosives, could be run into the west entrance of the tunnel and detonated. This project was canceled as the war ended.136 FEAF had also intended to emphasize napalm attacks, of proved worth in the Philippine campaigns, but there was time only for the preliminary tests. The Japanese already were licked. As Whitehead summed it up, the enemy "could decide that enough Nips had been killed or he could commit national suicide. He chose the former."137


133. USSBS, The Effects of Strategic Bombing on Japan's War Economy, pp. 61-65.

134. Ibid., p. 44.

135. Msg. WAR-65143, AFIJT to CINCSWPA, 7 Apr. 1945.

136. Msg. CX-30940, CINCAFPAC to Guam, 5 Aug. 1945; msg. A-80388, CG FEAF to WD, 7 Aug. 1945; msg. CX34703, CINCAFPAC to WD, 18 Aug. 1945.

137. Ltr., Whitehead to Chennault, 21 Aug 1945.
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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by ChristopherPerrien » 24 Feb 2013 21:21

Any ideas/sources on this silly "Javaman program ". I don't recall having heard heard of them before. Was this basically a remote controlled PT boat loaded with explosives? The 85 ft length points towards possibly a modified USAAF crash boat built by Mateo Corp. ? Were any actually built and tested?

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by phylo_roadking » 24 Feb 2013 21:56

OP, I can't help noticing there's a bit of a disagreement between -
After the Javaman program was cancelled, the Kanmon tunnel was
assigned to the 20th Air Force bombers, which firebombed both Moji and
Shimonoseki, which were either end of the electric railway tunnels.
...and...
It was recognized that the Kammon Tunnel between Kyushu and Honshu was the most important single transportation target in Japan,135 but the target was being saved until four disguised air rescue boats, remotely controlled and each loaded with 25 tons of high explosives, could be run into the west entrance of the tunnel and detonated. This project was canceled as the war ended.
Seems to be two conflicting dates for the cancellation of JAVAMAN..."before" the end of the war and "at" the end of the war.
Twenty years ago we had Johnny Cash, Bob Hope and Steve Jobs. Now we have no Cash, no Hope and no Jobs....
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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 25 Feb 2013 13:14

>>Was this basically a remote controlled PT boat loaded with explosives?

Yes.

>>The 85 ft length points towards possibly a modified USAAF crash boat built by Mateo Corp. ?

Yes. It was a modified 85-ft crash boat. Any information on the Mateo Corp would be appreciated.

>>Were any actually built and tested?

Yes. I will expand on this later as I have time.

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 25 Feb 2013 13:29

>>Seems to be two conflicting dates for the cancellation of JAVAMAN..."before" the end of the war and "at" the end of the war.

The US Military politics on closing down Javaman and reassigning the Kanmon Tunnel to the FEAF are in documents I don't have as yet.

I do know that General Krueger's 6th Army F.O. 74 and Adm Turner's Amphibious Forces order ComPhibsPac A11-45 (?) reassigned the Kanmon Undersea Railway Tunnel to the Far Eastern Air forces (FEAF) from 20th Air Force.

However, while those orders were being written and issued, General Hap Arnold had just rearranged the USAAF command relationships in the Pacific and put General Spaatz over General Kenney in a direct USAAF command relationship, with the 20th & 8th Air forces becoming the Strategic Air Forces Pacific, and the FEAF made up of the 5th, 7th, and 13th Air Forces becoming "Tactical Air Forces - Pacific" both of which were to be under Spaatz.

Mac Arthur OTOH still saw Kenney as being _his subordinate_ and not General Spaatz's. See the various Reports of General Mac Arthur on Operation Olympic and Coronet.

The war ended before that set too over command relationships took place. Javaman's use/non-use seems to be intimately tied up with that fuzzy command relationship.

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 25 Feb 2013 17:40

These are the best open source Javaman documents I have found to date --

1. Spycraft: The Secret History of the CIA's Spytechs from Communism to Al-Qaeda By Robert Wallace, Harold Keith Melton, Henry Robert Schlesinger -- page 14
One of the most forward thinking projects undertaken by Lovell's team was JAVAMAN, a remote-controlled weapon consisting of a boat packed with four tons of explosives. Using early television technology, a camera mounted on the boat's bow broadcast images to a plane circling fifty miles away where a crew member watching a monitor guided the boat to its destination, then triggered the explosives by remote control. Despite encouraging tests, the project was eventually dropped. 54 According to Lovell, the Navy abandoned the idea because it judged the explosive load as too dangerous to carry either by ship or submarine. 55
Stanley Platt Lovell, President of Lovell Chemical company, was head of OSS R&D.

2. Operatives, Spies, and Saboteurs: The Unknown Story of the Men and Women of World War 2's OSS By Patrick K. O'Donnel -- page 18

3. The Office of Strategic Services and Their Airborne Secrets by Dorothy Ringlesbach -- Page 39 - 41

4. Bombs, Cities, and Civilians: American Airpower Strategy in World War II (Modern War Studies) [Paperback]
Conrad C. Crane Page 85
Kenney never did get the support he had requested for the Pacific, but the plan JAVAMAN was later devised using Weary-Willy tecynology to guide robot boats with the B-17s. The boats were designed to destroy the Kammon Tunnel in the Shimonoseki Straits in September 1945, isolating the area in Japan to be invaded, but of course they were not needed. 22

22. Donald Hurchinson. chief of Far East Air Forces (FEAF) Air Staff to S.J. Chamberlin, G-3 SWPA 16 June 1945, Box 11061/42, and cable WX-44043, Washington to Guam, 5 August 1945, Box 11079/22, 373 F1les AFPAC, RG 338, NA. Suitland, Md.
5. Eddie Lorenzo Croft, Sr (1914 - 1989) - Find A Grave Memorial
http://www.findagrave.com/cgi-bin/fg.cg ... 618&df=all&
Maternal grandfather of fallen US Navy SEAL Tyrone Snowden Woods who died on September 12, 2012, in Benghazi, Libya. Tyrone's grandfather was a member of the Office of Strategic Services. As a radio/radar operator, he flew many missions out of the Marianna Islands, participating in the Pacific Theater campaign on bombing missions over Japan. The OSS Department lent him to the Navy, sending him to Havana, Cuba, where his team was a part of Project Javaman. The purpose of the project was to ram PT boats into Japanese aircraft carriers. The project was never used and remained classified for many years. Sgt. Croft received letters of commendation for his work in WWII from General Donovan and President Harry S. Truman, among others. He left military service in January of 1946 and returned home to Oregon and his wife. His passion was always electronics and mechanics, and he continued to repair radios and televisions for friends and family.

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 25 Feb 2013 21:24

These are the referenced messages cited in the open sources thus far in date order:

1) War Department to Mac Arthur -- Msg. WAR-65143, AFIJT to CINCSWPA, 7 Apr. 1945.

2) CoS FEAF to Mac Arthur G-3 -- Donald Hurchinson. chief of Far East Air Forces (FEAF) Air Staff to S.J. Chamberlin, G-3 SWPA 16 June 1945, Box 11061/42,

3) War Department to either 20th Air Force or Adm Nimitz -- cable WX-44043, Washington to Guam, 5 August 1945, Box 11079/22, 373 F1les AFPAC, RG 338, NA. Suitland, Md.

4) Mac Arthur to either 20 Air Force or Adm Nimitz -- Msg. CX-30940, CINCAFPAC to Guam, 5 Aug. 1945;

5) General Kenney to War Department -- Msg. A-80388, CG FEAF to WD, 7 Aug. 1945

6) Mac Arthur to War Department -- Msg. CX34703, CINCAFPAC to WD, 18 Aug. 1945.


Notes --

a. CINCSWPA and CINCAFPAC are both titles held by Gen. Douglas Mac Arthur
b. Both the 20th Air Force/Strategic Air Forces-Pacific and the Pacific fleet were based on Guam in August 1945.

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by ChristopherPerrien » 25 Feb 2013 23:07

Mil-tech Bard wrote:>>Was this basically a remote controlled PT boat loaded with explosives?

Yes.

>>The 85 ft length points towards possibly a modified USAAF crash boat built by Mateo Corp. ?

Yes. It was a modified 85-ft crash boat. Any information on the Mateo Corp would be appreciated.

>>Were any actually built and tested?

Yes. I will expand on this later as I have time.
About the 85' crash boat. The designer of the 85' crash-boat was Dair M. Long. Who worked for Mateo Corp. of South Carolina as a boat designer.He also taught at University of Michigan. Mateo was the sole builder of the 85'ft crash-boat. Futher reading points, I gather towards both Mateo and Mr. Long becoming part of the Miami Shipbuilding Corp. designing/working on and building Hydrofoils for the CIA and various other government agencies. Mateo Corp disappears sometime tween 45-48?

Some stuff can be learned by reading this site http://www.warboats.org/crashboat.htm

Examplehttp://www.warboats.org/images/jpg/Cras ... 3Issue.JPG but all the pages are of interest

and this gemhttp://www.warboats.org/psmhf.htm :) Which mentions Mr. Long and the 85' boat in some detail

Apparently MR. Long was one of the original/true pioneer of Hydrofoils, yet is little known. I ran across a very interesting excerpt from another designer of Hydrofoils that got into alot of "black project" Hydrofoil work post-war,
http://www.foils.org/miami.htm

A very intersting site in itself http://www.foils.org/pioneers.htm

Past all this the history of the crash-boat becomes the beginning history of the Brown -Water Navy, Going into various Nam vets stories, starting on crash boats which were then replaced by PBM's.

Ther

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 27 Feb 2013 04:40

It seems my memory regards Tall boy was not too far off.

See:

http://www.dtic.mil/dtic/tr/fulltext/u2/b972848.pdf
The equipment tested was the B-29 airplane, Serial No. 42-61577, modified to incorporate provisions for hoisting, carrying and releasing one 12,000-lb. Tall Boy bomb.
and
The performance characteristics that my be expected of
the subject airplane carrying one Tall Boy bomb are as follows:

(1) At target altitude gross weight, the operational
ceiling (300 feet per minute rate of climb) is 27,000
feet density altitude.

(2) Approximately 50 minutes are required to climb from
5,000 feet to the operational ceiling at a starting
gross weight of 118,000 pounds. (This gross weight
is comparable to that of the normal combat airplane
at the start of climb to altitude on a normal high 0
altitude combat mission).

(3) A reduction in true air miles per fuel gallon of
approximately 5.5 percent can be expected with the
bomb on board.

(4) A reduction of approximately 11.8 percent in true
air miles per fuel gallon can be expected on the
return cruise without the bomb.

(5) Based on the above figures, the maximum radius of
action with one Tall Boy bomb and usable fuel
load of 6,600 gallons is 1,320 air miles with a 600
gallon fuel reserve.

(6) So unusual flight characteristics are evident in the
airplane with or without the bomb.
The Grand Slam stuff --

http://www.sirbarneswallis.com/Bombs.htm
The Big Bombs - Grand Slam

The successful use of Tallboy led to the Ministry of Aircraft Production finally giving the go-ahead in July 1944 for the production of the larger (22,000lb) variant, now codenamed Grand Slam, for delivery in early 1945 - this was the ten-ton deep penetration bomb conceived by Wallis five years earlier. Its greater size required further development of techniques for making the casing, and meant that few places could machine the casing (it took two days for the initial casting to cool sufficiently for machining)! Although on paper well above the maximum load for a Lancaster, the modifications made to the B.1 Specials included the removal of gun turrets allowing the aircraft to carry Grand Slam up to an acceptable drop height (its greater size meant also that the Lancasters' bomb bay doors had to be removed entirely).

Its first use was against the Bielefeld Viaduct - 3,000 tons of bombs (including Tallboys) had already been dropped on it with little result, but Grand Slam brought it down on 14th March 1945 (the first Grand Slam had been test dropped in the New Forest the day before). Grand Slam was used against similar targets to Tallboy (often a raid would include both types of bomb), and again caused remarkable destruction wherever it was used - the Arnsberg, Arbergen, Neinburg and other bridges were also to be felled by the bomb. In total, 41 Grand Slams were dropped during the war.

The Americans were also producing Tallboys and Grand Slams by early 1945 (originally 400 were ordered from the UK and 200 from the US). There were plans to send 617 Squadron to the Pacific to use Tallboy and Grand Slam against targets in Japan, but in August 1945, bombs of far greater power brought the war to a close (these were dropped with an average error of 300 yards, which was laughable compared to the accuracy achieved by 617 Squadron by that time, although this was of little consequence)! After the war, bomb penetration tests with Tallboy and Grand Slam were conducted. Tallboys and Grand Slams were also carried experimentally by American B-29s (Operation Ruby) either recessed in the bomb bay with doors removed, or slung under the wings. The Americans also used the British-designed 4,500 lb rocket assisted Disney bomb to achieve greater penetration by force rather than by weight alone, although they did also develop their own 44,000lb version of the earthquake bomb, the T12 - this was tested using a B-29, but it could barely get off the ground with it (even with a light fuel load).

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 27 Feb 2013 05:02


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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 28 Feb 2013 02:00

The link below gives information on USAAF/USAF super heavy bomb development.

Air University Review, March-April 1967
The Extra-Super Blockbuster
Dr. William S. Coker

http://www.airpower.maxwell.af.mil/airc ... coker.html

The short story as far as the Kanmon tunnel is concerned was that -- assuming the A-bomb failed to achieve surrender -- the first operational Tall Boy/Grand Slam bomb delivery system deployed in the Pacific was going to be 617 Squadron Lancaster's of the UK "Tiger Force"

See Tiger Force TO&E here:

http://en.wikipedia.org/wiki/Tiger_Force_(air)

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Re: Kanmon Undersea Railway Tunnel & the Invasion of Japan

Post by Mil-tech Bard » 28 Feb 2013 18:37

ChristopherPerrien wrote: About the 85' crash boat. The designer of the 85' crash-boat was Dair M. Long. Who worked for Mateo Corp. of South Carolina as a boat designer.He also taught at University of Michigan. Mateo was the sole builder of the 85'ft crash-boat. Futher reading points, I gather towards both Mateo and Mr. Long becoming part of the Miami Shipbuilding Corp. designing/working on and building Hydrofoils for the CIA and various other government agencies. Mateo Corp disappears sometime tween 45-48?

Some stuff can be learned by reading this site http://www.warboats.org/crashboat.htm

Examplehttp://www.warboats.org/images/jpg/Cras ... 3Issue.JPG but all the pages are of interest

and this gemhttp://www.warboats.org/psmhf.htm :) Which mentions Mr. Long and the 85' boat in some detail

Apparently MR. Long was one of the original/true pioneer of Hydrofoils, yet is little known. I ran across a very interesting excerpt from another designer of Hydrofoils that got into alot of "black project" Hydrofoil work post-war,
http://www.foils.org/miami.htm

A very intersting site in itself http://www.foils.org/pioneers.htm

Past all this the history of the crash-boat becomes the beginning history of the Brown -Water Navy, Going into various Nam vets stories, starting on crash boats which were then replaced by PBM's.

Ther
There were three types of Javaman developed based on the A-2 (34 ft length by 8.5 ft beam), A-3 (37-ft Length by 11.5 ft beam) and A-5 USAAF target boats.

A total of 12 A-5 type boat bombs were built as of June 1945. Four of these A-5 boats were to be used for the Kanmon Undersea Railway Tunnel (KURT) attack.

These A-5 Javman boats were 85 feet long w/20-ft beam, were powered by two 1.250 HP packard engines running on high octaine aviation gasoline and had a gross weight of 190,000 lbs. They had a rated speed of 42 miles per hour (MPH) empty and of 30 MPH fully loaded with 25 tons of depth charges. These boats had a 700 mile range with a full load of fuel.

The OSS oufitted the four KURT mission boats with a fishing boat exterior and a volunteer crew to get them through Japanese nightly patrols after launching from either a US Navy Fast Destroyer transport (APD) or a Fleet boat (SS). This crew was supposed to be picked up by sub after they abandoned ship.

The pick up was a tricky proposition as the Javaman guidance employed a commercial bendix control system that could be set remotely by a B-17 control plane. These control planes had both SCR 717B radars and active infrared television links -- adapted from the "Weary Willie" robot bomber -- for long range radar control and close range night time terminal guidance.

Bandwidth and remote operator limits required two B-17 controller aircraft as each control plane could only guide two Javaman boats simultaniously.

The OSS crew had to get the Javaman boats close after launch, make sure their high tech equipment was operational and did not fall into Japanese hands and be sure there was enough B-17 control to ensure hits before they bailed for submarine pick up.

Not for nothing was the following statement in the documents I read -- "It is also possible to detonate the charge at the will of the operator."

They were not just talking about the B-17 operator!

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