Dec.7'41: A Day That Nobody Bombed Panama !

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#256

Post by phylo_roadking » 30 Jan 2009, 23:12

...but perhaps most importantly of all for your WI is the fact that they ARE MAGIC decrypts, and the U.S. Army (in charge of intelligence in the Canal Zone) had them...i.e. they were monitoring the JAPANESE CONSUL AND HEAD OF THE JAPANESE NETWORK IN PANAMA - thus they WOULD have been aware if he HAD been supplying daily data on waether, lake water level and gate position.... :wink:

Now I know "military intelligence" is a contradiction in terms :lol: but IF anyone had been gathering data in the Canal Zone on the water level in Gatun lake and the position of the spillway gates, in late 1941 they would have been doing it FOR Minister Akiyama! And as his communications were being monitored and decrypted...the Americans would have KNOWN that this data was being gathered. And it really doesn't take too much of a stretch of the imagination to work out why.

Your cadre of loyal Japanese agents would have given the game away early on.

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#257

Post by phylo_roadking » 31 Jan 2009, 01:33

And just to copperfasten that...
From: Panama (Akiyama)
To: Tokyo
October 6, 1941
J-19
#194

The result of my investigations, as I reported in my secret letter #142 [a] are as follows:

1. The airplane bases which the United States is constructing are located at La Chorrera in Panama province, (please refer to part 4 of my #149 [a]) Chitre in Herrera province, Mensabe in Los Santos province and at Remidios and Las Ra-Hasu in Chiriqui province

2. The Panamanian airports already constructed which will be converted into military establishments are the ones at David in Chiriqui province and Paidonya outside the limits of Panama City.

3. Airports which have been surveyed but because of the poor condition of the terrain have not been constructed, are the airports at Guarare in Los Santos province and at eight other projected points.

ARMY 24465 Trans. 11/7/41 (2)
NOTE THE DATE....just a confirmation that the Army were decoding and translating Akiyama's communications BEFORE December 7th, 1941...so they would definitely have had advanced warning of his interest in Gatun Lake and the gates...


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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#258

Post by phylo_roadking » 31 Jan 2009, 02:17

And just in case there should be ANY more question on how things worked in the Panama and the Canal Zone...remember, the December 1940 agreement with President Arias extended these to Panama under the American-dominated Joint Air Board...
EXECUTIVE ORDER 8251
REGULATIONS GOVERNING THE ENTRANCE OF FOREIGN AND DOMESTIC AIRCRAFT INTO THE CANAL ZONE, AND NAVIGATION THEREIN

September 12, 1939

By virtue of and pursuant to the authority vested in me by section 14 of title 2 of the Canal Zone Code, as amended by the act of July 9, 1937, 50 Stat. 486 (U.S.C., title 48, sec. 1314 a) I hereby prescribe the following regulations governing the entrance of foreign and domestic aircraft into the Canal Zone, and navigation of such aircraft within the Canal Zone.

SEC. 1. Canal Zone set apart as military airspace reservation. The airspace above the Canal Zone, including the territorial waters within the three-mile marine boundary at each end of the Canal, is hereby set apart as and declared to be a military airspace reservation, to be known as the 'Canal Zone Military Airspace Reservation.'

SEC. 2. Unlawful navigation of aircraft in military airspace reservation. It shall be unlawful to navigate any foreign or domestic aircraft into, within, or through the Canal Zone Military Airspace Reservation otherwise than in conformity with this Executive order: Provided, however, that none of the provisions of this order shall apply to military, naval, or other public aircraft of the United States.

SEC. 3. Authorization for entrance of aircraft into the Canal Zone Military Airspace Reservation, and navigation therein. Aircraft, foreign or domestic, shall be navigated into, within, or through the Canal Zone Military Airspace Reservation only under and in compliance with an authorization granted after the effective date of this order (a) by the Civil Aeronautics Authority in the case of civil aircraft, and (b) by the Secretary of State in the case of all other aircraft. Such authorization shall be granted only after consultation with the Secretary of War, and shall be subject to the further rules and regulations contained in or issued under this order, as well as those applicable generally to the entrance of aircraft into, and their navigation within or through, the Canal Zone Military Airspace Reservation. Application for such authorization shall be made (a) to the Civil Aeronautics Authority for flights by domestic civil aircraft, and (b) to the Secretary of State for flights by all other aircraft. All applications shall, unless otherwise directed by the Secretary of State or the Civil Aeronautics Authority, so far as either has jurisdiction with respect to particular classes of flights under this order, and with the agreement of the Secretary of War, set forth (a) the name, nationality, and address of the owner and of the pilot of the aircraft, (b) the make, model, and type of aircraft and information as to the registration thereof, (c) the registration marks displayed on the aircraft, (d) the names and nationalities of all persons aboard the aircraft, including passengers and crew, (e) the itinerary of the flight, (f) the purpose of the flight, (g) the expected time of arrival and duration of the stop within the Canal Zone, and (h) a statement as to firearms and cameras, if any, to be carried. In case any persons on board the aircraft, including passengers and crew, are in any way connected, either directly or indirectly, with the civil, military, or naval services of any foreign nation, in addition to designating such persons by name and nationality, the application shall contain a statement showing their connection with such service.

SEC. 4. Aircraft operated by and transporting only citizens of the United States or its possessions. Aircraft operated by and transporting only persons who are citizens of the United States or its possessions, for which authorization has been granted under provisions of this order to be navigated into, within, or through the Canal Zone Military Airspace Reservation, shall nevertheless not be so navigated into, within, or through such reservation unless the following conditions, or such of them as have not been specifically waived in each case as provided in section 6 hereof, are complied with:

(a) Prior to departure from the last point of landing before reaching the Canal Zone, the person in responsible charge of the aircraft shall notify the Governor of The Panama Canal, hereinafter referred to as the 'Governor', preferably by radio, of the probable time of arrival and the crusing altitude and speed.

(b) Such aircraft shall enter the Canal Zone Military Airspace Reservation via the prescribed route for private aircraft, and shall follow said route to, and land at, the landing area designated by the Governor, and such aircraft shall not pass through the said airspace reservation without so landing therein.

(c) Immediately after landing in the Canal Zone, the pilot of the aircraft shall report to the Aeronautical Inspector of The Panama Canal for instructions, and shall observe the instructions received.

(d) All such aircraft shall have all cameras carried therein sealed before taking off from the last point of landing prior to arrival at the Canal Zone Military Airspace Reservation, and all such cameras must remain under seal while within the said reservation.

(e) Without the authorization of the Governor, no arms, ammunitions, or explosives, except small arms, shall be carried aboard such aircraft.

(f) While within the Canal Zone Military Airspace Reservation, all aircraft shall be navigated in conformity with instructions or authorization of the Governor.

SEC. 5. Aircraft operated by or transporting persons who are not citizens of the United States or of its possessions. Aircraft operated by or transporting persons who are not citizens of the United States or its possessions, for which authorization has been granted under provisions of this order to be navigated into, within, or through the Canal Zone Military Airspace Reservation, shall nevertheless not be so navigated into, within, or through said reservation unless the following conditions, or such of them as have not been specifically waived in each case as provided in section 6 hereof, are complied with for each flight of such aircraft:

(a) The term 'flight' as used herein shall signify one or a number of aircraft under the command of or in responsible charge of a single person.

(b) Not over twelve aircraft shall be included in one flight.

(c) Prior to departure from the last point of landing before reaching the Canal Zone, the commander or the person in responsible charge of the flight shall notify the Governor, preferably by radio, of the probable time of arrival and the cruising altitude and speed.

(d) The flight shall approach the Canal Zone following commercial air lanes to a rendezvous point, outside of the Canal Zone, designated by the Governor and announced by him to the Secretary of State or the Civil Aeronautics Authority.

(e) On approaching the Canal Zone, the flight shall be met at the rendezvous by an official escort of aircraft from the Canal Zone and shall be escorted from the rendezvous point via a route prescribed by the escorting aircraft to a landing area in the Canal Zone. All such aircraft entering the Canal Zone Military Airspace Reservation shall land in the Canal Zone at the landing area designated by the Governor, and no aircraft shall pass through the said airspace reservation without so landing therein.

(f) Immediately after landing in the Canal Zone, the commander or the person in responsible charge of the flight shall report to the Aeronautical Inspector of The Panama Canal for instructions, and shall observe the instructions received.

(g) A similar procedure with escort shall be required in leaving the Canal Zone.

(h) Without the authorization of the Governor, no arms, ammunition, or explosives, except small arms, shall be carried aboard such aircraft.

(i) All such aircraft shall have all cameras carried therein sealed before taking off from the last point of landing prior to arrival at the Canal Zone Military Airspace Reservation, and all such cameras must remain under seal while within the said reservation.

(j) While within the Canal Zone Military Airspace Reservation, all aircraft shall be navigated in conformity with instructions or authorization of the Governor.

SEC. 6. Waiver of application of certain sections of order. The Secretary of State or the Civil Aeronautics Authority, so far as either has jurisdiction with respect to particular classes of flights under this order, and with the agreement of the Secretary of War, may waive the application of all or any part of the provisions of sections 2, 3, and 4 of this order.

SEC. 7. Authority of Governor to administer order and make detailed regulations. Except as otherwise specifically provided herein, the provisions of this order shall be administered and enforced by the Governor, and the Governor is hereby authorized to make such detailed regulations as may be necessary to carry into effect the provisions of this order.

SEC. 8. Punishment for violations. Any person who shall violate any of the provisions of this order shall be punishable, as provided in section 15 of title 2 of the Canal Zone Code, supra, by a fine of not more than $500, or by imprisonment in jail for not more than one year, or by both.

SEC. 9. Order subject to prior order and proclamation; revocation of prior orders and regulations. The provisions of this order shall be administered subject to the provisions of Executive Order No. 8232 of September 5, 1939, entitled 'Control of The Panama Canal and the Canal Zone', and the provisions of Proclamation No. 2350 of September 5, 1939, entitled 'Prescribing Regulations Concerning Neutrality in the Canal Zone.' Executive Order No. 4971 of September 28, 1928, designating the Secretary of State to receive and pass upon all applications for the privilege of operating commercial aircraft between the Canal Zone and foreign countries, is hereby revoked; and all other Executive orders and all regulations of the Secretary of State are hereby revoked in so far as and to the extent that they are in conflict with this order.

SEC. 10. Effective date. This order shall take effect ninety days after the date hereof.

FRANKLIN D. ROOSEVELT
THE WHITE HOUSE,
September 12, 1939.

Exec. Order No. 8251, 4 FR 3899, 1939 WL 4011 (Pres.)
:wink:

So as you can see from Sections 3, 4 and 5...it doesn't matter if they're recognised as "domestic" or "foreign" aircraft - if they don't comply with ALL those regulations...

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#259

Post by phylo_roadking » 31 Jan 2009, 03:10

And just in case there might be some thought that the garrison of the Canal Zone might still be sitting on their thumbs on December 7th...
War Warning Message from Chief of Naval Operations
Nov. 27, 1941
FROM: Chief of Naval Operations

ACTION: CinCAF, CinCPAC

INFO: Cinclant, Spenavo

272337

This dispatch is to be considered a war warning. Negotiations with Japan looking toward stabilization of conditions in the Pacific have ceased and an aggressive move by Japan is expected within the next few days. The number and equipment of Japanese troops and the organization of naval task forces indicates an amphibious expedition against either the Philippines, Thai or Kra Peninsula or possibly Borneo. Execute an appropriate defensive deployment preparatory to carrying out the tasks assigned in WPL 46. Inform district and Army authorities. A similar warning is being sent by War Department.

Spenavo inform British. Continental districts Guam, Samoa directed take appropriate measures against sabotage.

Copy to WPD, War Dept.
Army Alert Sent by Chief of Naval Operations:
Nov. 28, 1941
FROM: Chief of Naval Operations

ACTION: Com Pnncf, Com Psncf

INFO: Cincpac Com Pncf

28----

Refer to my 272338. Army has sent following to commander western defense command.

Negotiations with Japan appear to be terminated to all practical purposes with only the barest possibilities that the Japanese Government might come back and offer to continue. Japanese future action unpredictable but hostile action possible at any moment. If hostilities cannot repeat not be avoided the United States desires that Japan commit the first overt act. This policy should not repeat not be construed as restricting you to a course of action that might jeopardize your defense. Prior to hostile Japanese action you are directed to undertake such reconnaissance and other measures as you deem necessary but these measure should be carried out so as not repeat not to alarm civil population or disclose intent. Report measures taken. A separate message in being sent to G-2, Ninth Corps Area re subversive activities in the United States. Should hostilities occur you will carry out the tasks assigned in Rainbow five so far as they pertain to Japan. Limit dissemination of this highly secret information to minimum essential officers. Unquote. WPL 52 is not applicable to Pacific area and will not be placed in effect in that area except as now in force in southeast Pacific sub area and Panama naval coastal frontier. Undertake no offensive action until Japan has committed an overt act. Be prepared to carry out tasks assigned in WPL-46, so far as they apply to Japan in case hostilities occur.
In other words - the Army and Naval commands were NOT told to avoid any action - they were told to avoid "offensive" actions. If you've obtained AAFHS-42, you'll be aware that it's made quite clear in there that the full roster of USAAF activities and the patrolling of Canal Zone and Panamanian airspace was very specifically regarded as a DEFENSIVE action :wink:

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#260

Post by glenn239 » 31 Jan 2009, 18:33

Yes indeed your 1934 anti-torpedo nets are are still there. And probaly will be for several months of real time until I can head back down the the US archives for more research.
I think that if a plan is so fragile that it cannot even withstand something as mundane as torpedo nets, then its time to re-examine the whole thing.
Sort of take a Galapagos jumping-off point out of the equation...if THIS is the information that Tokyo has about USN operations - that they covered the Galapagos...
That would be checkmate for the proposed scheme then.

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#261

Post by robdab » 31 Jan 2009, 21:05

phylo_roadking, you wrote,

Here we have a nice two-line drawing of the Chitose BEFORE the large crane and derrick modification Robert suggests -
Image
...whereas HERE is a similar vierw of the Akitsushima and its crane...
Image

Now, a few minutes with a printed copy of each, a calculator and a steel engineers' ruler indicted that the afterdeck of the Chitose is 58.5 metres long, from the rear of the elevator housing - the bit that looks like a multistorey carpark? :lol: - to the rear of the ship. THIS however requires removing EVERYTHING there including the two seaplane-handling cranes just immediately aft of the elevator housing....

While a similar process indicates that the base if that large crane on the Akitsushima is somewhere between 12 and 14 metre wide...

THUS the Chitose has only some 46.5-44.5 metres free decking to carry H6K's....which are EACH 25 metres long!!! Carrying TWO rather staggered, positioned like bits of a jigsaw and well-lashed down is possible - just about - BUT THERE IS ABSOLUTELY NO WAY IT CAN CARRY A THIRD.


If you were to go to http://www.globalsecurity.org/military/ ... pan/av.htm
you would see two drawings that more closely resemble the ATL Chitose conversion that I had in mind. Both the Mizuho and the Nisshin show that the large central platform could be partially removed so as to be able to accomodate 3 Mavis. "Tis not that difficult.

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#262

Post by robdab » 31 Jan 2009, 21:15

Sid Guttridge, you wrote,

One can lead a horse to water, but one can't make him drink. If you don't have enough interest in your own subject to follow up sources you requested, then there is little more I can do for you. - What part of my reference to finding a copy on eBay did you not understand ?

As a matter of interest, in the light of the discussion above, would you modify your original plan?
If so, could you put up a modified version?
- Certainly but I need to find another important target on Panama for my ATL Japanese to attack, first.

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#263

Post by phylo_roadking » 31 Jan 2009, 21:23

If you were to go to http://www.globalsecurity.org/military/ ... pan/av.htm
you would see two drawings that more closely resemble the ATL Chitose conversion that I had in mind. Both the Mizuho and the Nisshin show that the large central platform could be partially removed so as to be able to accomodate 3 Mavis. "Tis not that difficult.
Robert, I'm VERY disappointed that your knowledge of the essential parts of your LONG-debated (in many locations) WI is SO poor...

Readers can take a look at http://www.globalsecurity.org/military/ ... -schem.htm and see the REAL two-line illustration of the Mizuho....yes you can remove the central platform - or rather take the Chitose into port and spend months rebuilding her elevator....BUT YOU CAN'T REMOVE THE TOWERS. So while you may actually fit a third Mavis aboard...it can only be loaded by a shore crane and it's STILL STUCK BETWEEN THE ELEVATOR TOWERS, with no way for the crane at the rear to lift it out from between them!!! :lol: :lol: :lol:

May I suggest you actually THINK about what you're looking at - same as you didn't do with your Tainter gate and Vertical Lift gates - before you post?

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#264

Post by robdab » 31 Jan 2009, 21:31

phylo_roadking,

The Chitose has a range of 7,800 nautical miles...about the distance from the Home Islands to the Galapagos. So she'll have to take a fleet oiler with her to be able to contemplate getting home again. - My thread opening posting already mentioned the inclusion of tanker supprt for my ATL Chitose.

Please try to keep up.

And here at long last is something I've been looking for - an H6K Mavis complete with torpedos! - My thread starting post contains a URL for the same photo.

Image

Please try to keep up.

Also, I believe that the Mavis design did not include retractible wheels. It was a water lander only AFAIK. The photo shows it mounted on a detachable carriage that was used to bring them ashore. I do not believe that such was strong enough for a dry land runway takeoff but am always open to being educated.

Robert, HOW many tons of extra explosive were you considering carrying on those rather thin supports??? - The explosives idea was glenn239's idea not mine. My only point was that a weight of explosive equal to the weight of a torpedo could be hung from each Mavis torpedo bracket.

So, now that your attack force is reduced by the carrying capacity of the Chitose to only TWO aircraft - No, three Mavis on my ATL Chitose.

....and given that at Pearl Harbour the hit rate for torpedos was only 50% - 26 out of 40 hit which is 65% with flak. I'd expect 4 gate hits although the results achieved by the Americans at the Hwachon Dam in Korea would indictae that asuming even more might be resonable.

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#265

Post by phylo_roadking » 31 Jan 2009, 21:35

As a matter of interest, in the light of the discussion above, would you modify your original plan?
If so, could you put up a modified version?
- Certainly but I need to find another important target on Panama for my ATL Japanese to attack, first.
...And I recommend that you remember to figure in ALL that you've learned about American regulation of Canal Zone and Panamanian airspace, the frequency of patrol flying, the standing orders for aircraft readiness and alert status and the pursuit & interception of unidentified and unauthorised/uncleared aircraft of ANY nationality, the US Army guarding installations on the Canal and in the Canal Zone, the civilian and USN aerial observers of your attack force flotilla in the Galapagos, the inability of Japanese agents to get up-to-date information to any attack force, and the fact that their network was being monitored by the MID.

And of course work out exactly why Adm. Yamamoto wouldn't be handing the person who suggests a plan with SO many individual points-of failure that have now been revealed wouldn't be handing him a sheet of paper for his wakizashi and the verbal expectation to NOT see him at dinner that night...

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#266

Post by phylo_roadking » 31 Jan 2009, 21:39

The Chitose has a range of 7,800 nautical miles...about the distance from the Home Islands to the Galapagos. So she'll have to take a fleet oiler with her to be able to contemplate getting home again. - My thread opening posting already mentioned the inclusion of tanker supprt for my ATL Chitose.
...with civilian liners and USN PBYs flying over them daily to observe them sitting in Neutral territory...are you actually expecting them NOT to report their presence??? :lol: :lol: :lol:
....and given that at Pearl Harbour the hit rate for torpedos was only 50% - 26 out of 40 hit which is 65% with flak. I'd expect 4 gate hits although the results achieved by the Americans at the Hwachon Dam in Korea would indictae that asuming even more might be resonable
Ahem...26 hit with a number of duds, which reduces the number downwards from your 65% towards 50%...

...and American torpedos are not Japanese ones. You can't equate the mechanical reliability of one manufactured item directly with that manufactured by the completely different industrial base of another nation! :lol: :lol: :lol:

One COULD for instance point at the 10-20 hour maintenance intervals and similar flying hours' to mechanical failure of the Jumo engines on the Me262... to the 180-hour service intervals on the Rolls Royce Welland on the contemporary Gloster Meteor... :lol: :P
So, now that your attack force is reduced by the carrying capacity of the Chitose to only TWO aircraft - No, three Mavis on my ATL Chitose.
Two. See my post above about your stranding the third in between two fixed elevator towers and out of reach of the stern crane to lift it out from between them!!! :lol: :lol: :lol:

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#267

Post by glenn239 » 31 Jan 2009, 23:00

A question for Rob and Phylo then.
What I want to know is, dropping all operational requirements and logistic assumptions from the equation, what is required to knock the Panama Canal out of operation for 3 months, in terms of amount of explosive delivered where?

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#268

Post by Simon K » 31 Jan 2009, 23:16

I would think only several thousand magnetic mines sewn at strategic points at the canal exits. Which I have been reliably informed, Japan did not possess.. I assume USN ships were degaussed?

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#269

Post by phylo_roadking » 01 Feb 2009, 00:05

Glenn - it requires the destruction of at least two locks in parallel not in line for sureity's sake (although traffic was restricted to one-way for the duration of the military control of the Canal, there were as we know parallel gates, and even a THIRD and larger one mooted at several points); or the destruction of BOTH enough of Gatun's spillway gates to ensure the lake drains AND the destruction of Madden to ensure it can't be replenished in a hurry.

HOWEVER - such a mission ALSO requires that the damage is ENOUGH to as you say keep it out of commission for three months or more....which means BOTH the degree of initial damage inflicted - AND the destruction of repair facilities....

For instance - one of the repetitive issues on Tanknet with Robert's initial mission profile is how the damaged or destroyed gates could be repaired. And it's been mentioned on here...

The answer to THAT is simple. And downstream :wink: the battleship graving dock at Balboa could throw up a gate sized plate or limpet patch from steelstock on hand within HOURS and have it sent up-canal by lighter and tugs; these same tugs - of which there are PLENTY in the Canal system - can position the lighter and hold it against the flow while the Army's Construction Engineers hoist the patch into place by its upper edge from winches etc on the spillway walkway. Then it's simply a case of clamping/wedging/cabling the plate in place assisted by the pressure of the outflow :wink: And using the rest of the gates to regulate outflow...not that any OUTFLOW regulation will be needed for a while!!! 8O This is something Robert has forgotten - that even IF they do ENOUGH damage to reduce the water level significantly...doing so means the INTACT gates don't need to be used for some time!!! In fact - the Spillway Control Room staff will be sitting twiddling their thumbs for some time!!!

So the mission requires ENOUGH damage done that the Lake empties fast enough that it can do so BEFORE repairs are effected....remembering that it can ONLY go down as far as the edge of the sill the spillway gates sit in ANYWAY before the "involuntary outflow" halts!!!

Now, I'm not a mathematician, so perhaps someone else can do THIS sum - the surface area of the lake in feet times the twenty feet the water level can ONLY drop before it halts at the sill...to give us a cubic volume in feet. Then THIS is the amount that has to drain via the spillway gates at 10,000 ft per second times the number of damaged gates.

It's STILL going to be only a scratch calculation, of course the rate of outflow will reduce as the water level goes down...

AND OF COURSE THE WATER LEVEL GOING DOWN MAKES IT EASIER FOR THE SEEBEES TO WORK AT THE DAMAGED GATE(S) :wink: Once the level goes down to the sill of the gateway, there's ONLY another 10 meters of water until the bottom on that level section of the dam. They can work from a barge or dredger manouvered into place by tugs or warped in on cables winched from the bank on either side.

(Robert has also forgotten the HUGE amount of construction on hands in the Canal Zone during 1941. Not only was the ARMY carrying out construction works, airfield and base depot construction, building underground bomb stores and the bombproof underground Quarry heights Zone HQ...going by that reference of Robert's the NAVY had heavy construction workers on hands in the Zone at both ends of the Canal to call on! There will be an embarassingly HUGE number of repair troops AND know-how available in the hours and days after an attack!!!)

SO - a "successful" mission has to see the level of the Lake going down in as short a time as possible...the water reserve at Madden lost TOO...and enough of the possible repair resources in materiel, shipping and manpower spread ALL over the Canal Zone wiped out! :lol: :lol: :lol: Robert, do you want the Japanese to have invented the Atomic Bomb in 1941???

Glenn - even after all THAT - there's STILL the problem of how fast the NATURAL rainfall runoff can replenish the Lake. As the thread on Tanknet noted...
Ok, today the average rainfall in a year is 2970mm. 70% falling in the rainy season which lasts 6 month. Now if we presume a linear distribution, it means 350 mm rain in december.

Say an additional 100mm in January (usually 10 rainy day in December and 3 in January according to climatc data)
Now if we consider that the landscape would have a water flow of 30% (the rest being used by plants, held back etc.)

1800 square miles = 4662 km²
450 mm = 450 l/m²
450 x 0,3 = 150 l/m² = 0,15 m³/m²

So we get :

4662 km² = 4662000000 m² = 699300000 m³ = 699300000000 l = 24692796610 ft³ So that means roughly 10 days if we consider a water loss of 30.000 ft³/sec. (I will calculate this more closely considering depth and pressure later)

So in December in January the lake should get so much water flowing in, that it could compensate the loss of 10 days with four gates fully open.
December isn't the END of the rainy season, it's just the tapering off; it doesn't end precisely it runs into the start of January in some years.

The natural runoff from the end of the rainy season and the water stored in Madden means the lake can replenish quickly once the outflow is stopped...

The engineers therefore have the choice to either coffer the broken or holed gates - if they're just holed repair is simple anyway - or simply wait UNTIL the outflow halts at the gate sill and do their repairs THEN with no problems except normal engineering ones THEN release the water in Madden :wink:

Glenn - I honestly can't see a situation arising that guarantees the Canal being out of action for three months from an attack on the Spillway Gates EXCEPT if a VERY large number of the gates are totally destroyed. And even THEN it JUST goes down to the sill level! The more the damage, the faster it goes down to this level ONLY. Once repairs are made - the replenishment rate is the same no matter how much damage was done in the first place :lol:

Remember what I said early on about the depth of water STILL remaining in the Dam??? While ALL this repair work is going on, the authorities can have every dredger in Gamboa out and re-dredging the lane across the Lake...and of course given that that movement is still marginally possible even down at maximum outage - every SINGLE foot gained in replenishment improves the transit of ships actually ACROSS Gatun Lake! The lake doesn't NEED to be in any way FULLY replenished for THAT to resume with no problems!!! :D

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Re: Dec.7'41: A Day That Nobody Bombed Panama !

#270

Post by Simon K » 01 Feb 2009, 00:14

my nets are still there BTW

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