S Class Questions

ancient46 · 01-27-09, 02:55 PM

I've been working on setting the sub draft to make the game's subs look like as the official Navy photographs. However I have run into a problem with the S class. I can find lots of excellent examples of how the S-18 and S-42 types sit in the water but they do not match the sub modeled in the game. Many are much much different.

If I lower the sub to match almost all of the pictures I have and set the waterline at the bottom of the anchor the rear is too high. Here is a sketch of the 1944 S-20 to illustrate the problem. http://www.navsource.org/archives/08/0812507.jpg I am assuming the line drawn through the boat on the external view is the designed waterline.

If anyone can point me to a reference that pictures the S boat modeled in the game I would greatly appreciate it.

On a side note the S-20 was commanded by John Phillip Cromwell from 1936-1937. A SH4 attack method by Rockin Robbins and Nisgeis was named for this CMoH winner.

LukeFF · 01-27-09, 09:16 PM

The hull shape of the S class is based on the 1920s'-30s style of the hull, before the boats were modernized. A draft of 5.3 meters will put it where it needs to be historically correct while on the surface.

ancient46 · 01-28-09, 07:29 AM

I wish they had modeled an S class as one we would have seen in the war. I wish they had used a boat like the S 30 type.

Most of the information I found was that the safety Mod done before the war started included the marker buoys but the model does not have them, only the hatch. I found a design sketch of one of the later 18 types and I can work from that. I was going to leave out the S boats since I couldn't match it with any picture I had found. For me it is not worth changing the draft unless I can demonstrate a historical basis for the change.

LukeFF · 01-29-09, 02:19 AM

Quote:

Originally Posted by ancient46

I wish they had modeled an S class as one we would have seen in the war. I wish they had used a boat like the S 30 type.

Most of the information I found was that the safety Mod done before the war started included the marker buoys but the model does not have them, only the hatch. I found a design sketch of one of the later 18 types and I can work from that. I was going to leave out the S boats since I couldn't match it with any picture I had found. For me it is not worth changing the draft unless I can demonstrate a historical basis for the change.

Not to mention the hull type we have is for the S-18 group of boats. The hull for the S-42 had a noticeably different shape both near the stern and forward of the conning tower.

The interior model...ugh, don't even get me started on that abomination... :rotfl:

DaveyJ576 · 02-02-09, 12:50 PM

The drawings by Jim Christley that you have referenced on Navsource are quite accurate. The waterline shown on the drawings is probably a light load waterline. That is the waterline with no fuel, fresh water, stores, or weapons on board. The actual full load waterline would have been about 12-14 inches deeper. The torpedo tubes would not have been visible and the rudder would have been just below the surface, out of sight. It was also not uncommon for the boats to be slightly trimmed by the stern, leaving the boat with a slight up angle when at rest.

The safety mods done during the 1920's cut away part of the superstructure "skeg" that ran down from the end of the main deck to the rudder. This was done to allow the installation of an escape hatch in the motor room. However, the normal surface trim of these boats resulted in this escape hatch being underwater at all times.

Take a look at this picture:

http://www.navsource.org/archives/08/0813105.jpg

The safety mods also had rescue buoys installed at the aft end of the superstructure were the skeg was cut away. However, not all of the boats got these buoys right away. Some were not installed until 1941.

There was no significant difference in the hull shape of the later S-42 group as opposed to the earlier boats. The S-42 group was 6 feet longer and the conning tower fairwater was shaped differently (to accomodate a gun access trunk at the forward end), but other than that the hull shape was the same. What you might have been seeing were before and after photos of the skeg modification.

Some of the boats received extensive wartime modifications and this radically changed the visual outline. See photo of S-47 below:

http://www.navsource.org/archives/08/0815807.jpg

It is amazing that the waterline did not radically change as new guns, radar, sonars, and A/C were added.

ancient46 · 02-03-09, 02:36 AM

Well the problem I am having is finding the boat used for the games model. The best view I found was the S-18 taken in after 1943 http://www.navsource.org/archives/08/0812307.jpg. If I set the boat so that the water line matches the photo the rear of the boat with part of the screws is out of the water. I am trying to match screen shots in sh4 with the historical records. I want to make our screen shots look as if it were actually a color photograph taken during WW2. It was relatively easy until I hit the S class, then things got complicated.

01-27-09, 02:55 PM	#1
ancient46 Officer Join Date: Apr 2008 Location: Pennsylvania Posts: 239 Downloads: 108 Uploads: 1	S Class Questions I've been working on setting the sub draft to make the game's subs look like as the official Navy photographs. However I have run into a problem with the S class. I can find lots of excellent examples of how the S-18 and S-42 types sit in the water but they do not match the sub modeled in the game. Many are much much different. If I lower the sub to match almost all of the pictures I have and set the waterline at the bottom of the anchor the rear is too high. Here is a sketch of the 1944 S-20 to illustrate the problem. http://www.navsource.org/archives/08/0812507.jpg I am assuming the line drawn through the boat on the external view is the designed waterline. If anyone can point me to a reference that pictures the S boat modeled in the game I would greatly appreciate it. On a side note the S-20 was commanded by John Phillip Cromwell from 1936-1937. A SH4 attack method by Rockin Robbins and Nisgeis was named for this CMoH winner.

01-27-09, 09:16 PM	#2
LukeFF Silent Hunter Join Date: Apr 2005 Location: Riverside, California Posts: 3,610 Downloads: 41 Uploads: 5	The hull shape of the S class is based on the 1920s'-30s style of the hull, before the boats were modernized. A draft of 5.3 meters will put it where it needs to be historically correct while on the surface. __________________ ROW Sound Effects Contributor RFB Team Leader

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01-28-09, 07:29 AM	#3
ancient46 Officer Join Date: Apr 2008 Location: Pennsylvania Posts: 239 Downloads: 108 Uploads: 1	I wish they had modeled an S class as one we would have seen in the war. I wish they had used a boat like the S 30 type. Most of the information I found was that the safety Mod done before the war started included the marker buoys but the model does not have them, only the hatch. I found a design sketch of one of the later 18 types and I can work from that. I was going to leave out the S boats since I couldn't match it with any picture I had found. For me it is not worth changing the draft unless I can demonstrate a historical basis for the change.

02-02-09, 12:50 PM	#5
DaveyJ576 Officer Join Date: Nov 2008 Location: Norfolk, VA Posts: 241 Downloads: 30 Uploads: 0	The drawings by Jim Christley that you have referenced on Navsource are quite accurate. The waterline shown on the drawings is probably a light load waterline. That is the waterline with no fuel, fresh water, stores, or weapons on board. The actual full load waterline would have been about 12-14 inches deeper. The torpedo tubes would not have been visible and the rudder would have been just below the surface, out of sight. It was also not uncommon for the boats to be slightly trimmed by the stern, leaving the boat with a slight up angle when at rest. The safety mods done during the 1920's cut away part of the superstructure "skeg" that ran down from the end of the main deck to the rudder. This was done to allow the installation of an escape hatch in the motor room. However, the normal surface trim of these boats resulted in this escape hatch being underwater at all times. Take a look at this picture: http://www.navsource.org/archives/08/0813105.jpg The safety mods also had rescue buoys installed at the aft end of the superstructure were the skeg was cut away. However, not all of the boats got these buoys right away. Some were not installed until 1941. There was no significant difference in the hull shape of the later S-42 group as opposed to the earlier boats. The S-42 group was 6 feet longer and the conning tower fairwater was shaped differently (to accomodate a gun access trunk at the forward end), but other than that the hull shape was the same. What you might have been seeing were before and after photos of the skeg modification. Some of the boats received extensive wartime modifications and this radically changed the visual outline. See photo of S-47 below: http://www.navsource.org/archives/08/0815807.jpg It is amazing that the waterline did not radically change as new guns, radar, sonars, and A/C were added.

02-03-09, 02:36 AM	#6
ancient46 Officer Join Date: Apr 2008 Location: Pennsylvania Posts: 239 Downloads: 108 Uploads: 1	Well the problem I am having is finding the boat used for the games model. The best view I found was the S-18 taken in after 1943 http://www.navsource.org/archives/08/0812307.jpg. If I set the boat so that the water line matches the photo the rear of the boat with part of the screws is out of the water. I am trying to match screen shots in sh4 with the historical records. I want to make our screen shots look as if it were actually a color photograph taken during WW2. It was relatively easy until I hit the S class, then things got complicated.