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Silent Hunter 4

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Installing Silent Hunter 4 in Windows 7 Professional Edition X64

Patrol Charts for the Guerrilla Submarines Spyron Mod

Patrol charts are available for the following areas. You will need them if you are using the Guerrilla Submarines Spyron Mod.

Download All Patrol Charts for the Guerrilla Submarines Spyron Mod (posted: September 1, 2011)

Guerrilla Submarines Spyron Mod

The Guerrilla Submarines Spyron Mod is named for the Seventh Fleet's "guerrilla line" submarines, or "Spyron," as they were unoffically referred to. The Spyron activity was authorized in late 1942 by General Douglas MacArthur. He placed Commander Charles "Chick" Parsons in charge of the Spyron initiative to contact, organize, and supply American and Filipino guerrilla fighters across the Philippine islands. Parson's operations were carried out by means of special missions assigned to various submarines. The first mission was carried out by the USS Gudgeon (SS-211). On December 27, 1942, captained by Lieutenant Commander William Stovall, the Gudgeon embarked Major Jesus Villamor, six other Filipinos, and a ton of supplies including weapons, a radio, money, medicines, candy, and cigarettes, and departed Brisbane for the Philippines. On the night of January 14, 1943, Gudgeon put the men and supplies safely ashore on Negros Island. By the end of the war, nineteen different submarines undertook forty-two Spyron missions to the Philippines. Only one failed when the Seawolf was lost to friendly fire in September 1944.

In the Guerrilla Submarines Spyron Mod, I replaced all the stock personnel insertion and supply missions with missions that mirror the Fremantle-based Spyron and Allied Intelligence Bureau missions in the Philippine Archipelago, the Bismarck Archipelago, the Netherlands East Indies, Southeast Asia, and the Solomon Islands. There are also several early war resupply missions from Pearl Harbor to Corregidor and one other location in the Philippine islands. These missions are based on sources listed in the my bibliography, specifically Guerrilla Submarines, Allied Intelligence Bureau: Our Secret Weapon in the War Against Japan, United States Submarine Operations in World War II, The Coast Watchers, and Sink ‘Em All. I also referred to the official submarine war patrol reports resource listed in my bibliography.

All stock photo recons have been removed. I added thirteen new historically accurate photo recon missions. Theodore Roscoe's book has a great discussion of submarine photographic reconnaissance during the Pacific War. There were only thirteen formal submarine photographic reconnaissance missions. With the exceptions of Iwo Jima and Okinawa, they were all conducted in the Micronesia islands, starting in the Gilberts and ending at Palau. How it generally worked was the Commander Amphibious Forces would make a request to Admiral Nimitz to have a submarine conduct a recon at an area under consideration for amphibious assault. (As happened at Truk, sending air recon units often tipped off the Japs and they would move their fleet units to safe harbors and fortify defensive positions.) Nimitz would confer with ComSubPac to determine if a submarine was available to do the job and if the circumstances justified the risk. If Nimitz and ComSubPac agreed to do it, personnel from PRISIC (Photographic Reconnaissance and Interpretation Section Intelligence Center) were assigned to outfit the submarine with the necessary equipment and convert a section of the sub (usually the lower sound room) into a darkroom and laboratory. On all but one of the recons, two PRISIC photographers went on the mission. The new missions mirror the above thirteen recons. Each mission requires recons at more than one location. The key to doing them is to time the routes of enemy patrol craft (if present), run as quietly as possible, get within the zone, photograph the ships, and get out. I say ships because each location (except one) requires multiple photographs. Less formal photo recons were conducted. I added three such recon missions - at Christmas Island in the Indian Ocean, at Chichagof Harbor on Attu Island, and at Kavieng Harbor on New Ireland. So the total number of photo recon missions stays at sixteen as in stock, but they are all new.

The Guerrilla Submarines Spyron Mod provides fifteen American career start dates (Entry Points), beginning with December 1941. The next fourteen entry points follow at four-month intervals, e.g., March 1942, June 1942, September 1942, etc., but you can always use Kim Ronhof's Tbox (below) to change your patrol start date within the four month intervals. The Tbox tool is tied to a database of 150 Silent Hunter mission files that have been modified in full or partially. Thirty-seven of them have Type 5 objectives as the primary objective. In other words, when you change the game-assigned primary mission to one of these, or when the game assigns one to you, you will receive orders to deploy to a certain area and to search for and sink a specific tonnage amount (generally 10,000-tons) of enemy shipping. You are not tied to the specific area for a set time period (as in a Type 0 objective). The other missions are designated special operations (Spec Ops), such as photographic reconnaissance, lifeguard duty, personnel or supply insertion, or a special patrol assignment (Type 5 objective) as part of a task force or wolf pack (e.g., in the Battle of Midway, Battle of the Coral Sea, Battle of Truk, or Battle of Leyte Gulf). In the case of photo recons, lifeguard duty, and insertions, after you complete the primary Spec Op objective, you will receive orders within the game to deploy to a specific area where you will search for and sink enemy shipping (Type 5 objective) after the Spec Op objective has been completed successfully.

The topmost level of the mod archive incudes an Excel spreadsheet named "patrol-codes" which provides a summary of the 150 core missions included in the mod. In particular, it lists the flotilla a mission is assigned to as a potential objective in the dynamic campaign. It also lists the time period a mission will be available for selection by the game's decision mechanics. This information is helpful if you wish to use Kim Ronhof's Tbox to select a different mission. The mission ID numbers and names are listed in the spreadsheet. You will need this information when using the Tbox utility. Please note that the Entry Points correspond to the following time periods:

Entry Point 01 - December 1941
Entry Point 02 - March 1942
Entry Point 03 - June 1942
Entry Point 04 - September 1942
Entry Point 05 - December 1942
Entry Point 06 - March 1943
Entry Point 07 - June 1943
Entry Point 08 - September 1943
Entry Point 09 - December 1943
Entry Point 10 - March 1944
Entry Point 11 - June 1944
Entry Point 12 - September 1944
Entry Point 13 - December 1944
Entry Point 14 - March 1945
Entry Point 15 - June 1945

If you plan to manually select your patrol mission using Kim Ronhof's TBox, it is important to select a mission that is available for your flotilla and for the time period you are sailing in. The spreadsheet contains this information. Of course you can simply proceed without worrying about changing anything. The decision mechanics built into the game's AI will select and assign a mission to you appropriate to your flotilla's area of operations.

The mod has a total of thirteen flotillas – Pearl Harbor, Dutch Harbor, Fremantle, Brisbane, Midway Island, Tulagi, Mios Woendi, Majuro, Manus Island, Saipan, Guam, Subic Bay, and New Caledonia (Sub School). With the exception of New Caledonia, these are designated as forward operating bases for the three principal commands - Pearl, Fremantle, and Brisbane. Transfers to other flotillas can be accomplished via the telephone in the office.

Just for rookies new to Silent Hunter 4, I put a Sub School facility at Noumea, New Caledonia. The training missions assigned to that flotilla are conducted in a hot war zone as part of the dynamic campaign - students can transfer their career to a regular flotilla upon completion of one or all the training exercises. I created five training missions that mirror the types of objectives they will receive in a regular flotilla. The missions cover photo recons, lifeguard duty, insertions, and patrol type objectives.

The mod includes 206 new map locations - ports, villages, towns, islands, and waterways. I spent a considerable amount of time researching the Philippine Archipelago, the Bismarck Archipelago, New Guinea, and the Micronesia and Solomon island chains to ascertain the types of harbors and port facilities present during the war. I also wanted to ascertain the exact dates of occupation by the Japanese, the sizes of their garrisons, and the types of airdromes present. Some stock harbor locations will be conspicuously absent - Honiara, Melekeok, Saipan, Koror, Guam - just to name a few. This is because the harbors were not where the Dev Team put them or they just didn't exist. In making my changes I principally used Gordon L. Rottman's geo-military study (see bibliography) as the definitive source.

I added new dynamic traffic layers for the Solomon Islands, New Guinea, Bismarck Sea, Vogelkop Peninsula, Gilbert Islands, Marshall Islands, Mariana Islands, Caroline Islands, Palau Islands, and the Philippine Archipelago. Wherever the Japanese maintained a garrison we would expect to find harbor traffic and resupply convoys in transit to reinforce and sustain them. In some areas the stock traffic is nonexistent; in others it is insufficient. Having gotten a handle on the sizes, dates of occupation, and locations of the Japanese garrisons, I estimated the sizes and frequencies of supply convoys, and their transit routes. In doing this, the book The Japanese Merchant Marine in World War II was very helpful. In the Solomons, the strength of our air forces forced the Japanese to operate at night, using fast patrol craft and transports. So in that theater you can expect to find Tokyo Express units making supply runs.

I wish to thank Art Anker for allowing me to include his Sofu Gan mod in this archive. This is a brilliant piece of work which is described more fully below. Art also provided some edits to my localization file which changed torpedo data from the Metric to the Imperial system in the torpedo data screen. I also extend my thanks to Carotio for his Truk Atoll and Panama Canal Zone environmental mods, which I have included with some additions of my own. Finally, my thanks to Jace11 for his map labels mod, which I have also included with some additions.

The Guerrilla Submarines Spyron Mod has been tested in a clean (i.e., unmodded), stock install of Silent Hunter Wolves of the Pacific, v1.5.

The mod is v1.5 and JSGME friendly.

Please send any bug reports to me at the address posted in my Contact Me Web page.

Download the Guerrilla Submarines Spyron Mod version 1 (7-Zip archive) (posted: September 1, 2011)

Keyboard Shortcuts - Edits for the Commands.cfg file

The Silent Hunter 4 Commands.cfg file is in the following directory:

c:\Program Files\Ubisoft\Silent Hunter 4 Wolves of the Pacific\Data\Cfg\Commands.cfg

All edits should be made using Notepad or another plain text editor.

Make the Shift + B keys toggle Battle Stations on/off.


Make the Shift + G keys report your range at your current speed.


Make the Ctrl + W keys report the prevailing weather conditions.


Disable the Enter key from firing torpedoes.


This edit requires both Crtl + Enter keys be pressed to fire a torpedo, thus reducing the chance of firing one by mistake.

Silent Hunter 4 Generic Mod Enabler

The JonesSoft Generic Mod Enabler (version 2.3.1 or version 2.6.0) takes most of the hassle out of installing and uninstalling mods for your games. It has been tested on many games, including Silent Hunter III and Silent Hunter 4 Wolves of the Pacific, and should work with any mod-capable game.

The Mod Enabler is designed to be installed in the root folder of the game that you wish to mod. Before installing it, you should ensure that you have a clean, unmodded installation of your game, preferably with the latest patches installed.

Download the JonesSoft Generic Mod Enabler version 2.3.1

Download the JonesSoft Generic Mod Enabler version 2.6.0


Kim Ronhof's Electronic Cipher Officer (ECOPTC version 2.0.0 C)

The ECOPTC program converts plain text messages into enciphered text and deciphers enciphered messages. It uses a simulation of the coding machine used on American submarines in World War II. It adds an additional degree of realism to your Silent Hunter 4 adventures. The program will install and run in Windows XP, Windows Vista, and Windows 7.

Download the Electronic Cipher Officer (ZIP archive)

Kim Ronhof's Silent Hunter 4 Patrol Report Generator (version 5102) and Silent Hunter 4 Tools (Tbox)(version 2.0)

Tbox is a Single Patrol Generator for the dynamic American Career mode. It allows you to edit the dynamic career save file to change the patrol area (mission-objective file) you are assigned by the game, your boat's name, your name and rank, and your patrol start date. For those of you who are familiar with Hawk's Patrol Zone Selector for SHCE, Tbox accomplishes the same goal. The programs will install and run in Windows XP, Windows Vista, and Windows 7.

Download the Silent Hunter 4 Patrol Report Generator and Silent Hunter 4 Tools (ZIP archive)

SubSoWesPac Air Strike Mod

My biggest complaint about Silent Hunter 4's enemy airstrike configuration is that there are too many night attacks. While Japan did have competent night fighters in its arsenal, they were principally used as interceptors. In all my years of playing the original Silent Hunter, I did not ever come under attack by an enemy airplane at night and I do not recall reading about frequent night attacks against U.S. boats in the Pacific by Japanese aircraft, unless the boat was close to a Jap air base and its radar was detected by the enemy.

I have made my own modification to the game's "AirStrike.cfg" file. The sole change reduces the Night Strike Probability by 90% to 0.005, from the default value of 0.05. There are no other changes. All other values are unchanged - they are the same as the ones in the un-modded Silent Hunter 4. On my system, the AirStrike.cfg file is located at the following path.

c:\Program Files\Silent Hunter Wolves of the Pacific\Data\Cfg\AirStrike.cfg

The file is v1.5 and JSGME friendly.

Download the SubSoWesPac Air Strike Mod (ZIP archive)

Art Anker's Hull Numbers Mod

I highly recommend this mod. View Art's Readme for details.

Download the Hull Numbers Mod (ZIP archive)

Art Anker's Sofu Gan Mod

Sofu Gan (Lot's Wife) is a volcanic, deserted island with a summit height of 325 feet, located approximately 404 miles off the coast of Tokyo, in the southernmost tip of the Izu Archipelago. During World War II, it served as a navigational landmark for American submarines. Our submarines also used it calibrate their radar before entering the convoy lanes around Honshu. The stock game placed the shallow sea area there, but not the volcanic land mass. During the Pacific War, the Japanese used an area southwest of Sofu Gan as a staging area for major fleet units en route to Truk or the Palaus.

Thanks to Art Anker's excellent creativity and hard work, now it is in the game. Art experienced a host of frustrations and challenges in creating this work. But he never gave up. Job well done my friend. Congratulations!

The images below are thumbnails. Click on them for a larger image.

Lot's Wife thumbnail

Sofu Gan thumbnail

Download the Sofu Gan Mod (ZIP archive)