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Post by Rasputitsa on Dec 14, 2013 10:33:46 GMT -6
SAI uses a round world as real ships navigate on a round world. As Randomizer says, if you keep a straight course and don't adjust you will miss your goal, in SAI just as in real world navigation. It is quite noticeable in SAI even in the relatively short distances in the North Sea. If you set a course say from the Helgoland Bight to Sunderland and just let your ships go straight ahead, after a while you will see that you are in fact heading towards a point a little off from Sunderland. Hi FW: I am aware of your use, as in the old days of sailing of the Riemannian circle to navigate, and as you say, you have to have course corrections or you will miss your destination. In inertial navigation, you input your current location in degrees, minutes and seconds, your destination then three or four waypoints depending on the distance to travel. At each waypoint, course corrections will be made to travel successfully to the next waypoint. It's the same for surface navigation, which is where it was derived from. But, a navigator doesn't really do that, he uses a standard Mercator map, takes a reading of a nearby land form like a lighthouse on a point, then draws a straight line from that point on his map to the coordinates given for his destination. That line gives him his base course, and using variables like the wind, ocean currents and estimated speed of the ship derives arrival time. If you read the orders sent out by Jellicoe to the fleet, he provides specific coordinates for the meeting point. I am certain Beatty's chief navigator took a reading on the point as they exited the port and used that his current position.
This type of navigation is actually titled orthodrome navigation used for long distance surface navigation whereas for very short distances, loxodrome navigation. Since the former cuts meridians at varying angles, you have to do constant course corrections to maintain the line. It's the combined use of both, that is actually at work. All this can be and is represented by the Mercator projection map used by navigators and familiar to almost everyone.
It was just a suggestion, to give the newbies some realism. Thanks for listening.
I to took a navigation course as part of my training a loooong time ago and all that you say is true, but surely the realism we are trying to recreate is the decision process at admiral (fleet, or squadron commander) level, this degree of detail is happening at navigation officer level. At fleet commander level the questions are more likely to be 'give me a course for Sunderland', 'set an intercept course for ...........', or clearing the smoke downrange, positioning for tactical advantage, visibility and sun effects, etc., it's not leaning over a Mercator Chart worrying about precise navigation and waypoints, you only have to get within sighting range of friendly, or enemy formations, to achieve your objectives. In 1912 the Titanic and various other vessels transmitted the position of the sinking, they were all wrong, some by several miles. Precise navigation comes into play when the fleet breaks up for entering an anchorage, etc., alternatively there's the BBC Navy Lark's immortal navigation technique of 'left hand down a bit'.
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Post by oldpop2000 on Dec 14, 2013 11:07:03 GMT -6
Hi FW: I am aware of your use, as in the old days of sailing of the Riemannian circle to navigate, and as you say, you have to have course corrections or you will miss your destination. In inertial navigation, you input your current location in degrees, minutes and seconds, your destination then three or four waypoints depending on the distance to travel. At each waypoint, course corrections will be made to travel successfully to the next waypoint. It's the same for surface navigation, which is where it was derived from. But, a navigator doesn't really do that, he uses a standard Mercator map, takes a reading of a nearby land form like a lighthouse on a point, then draws a straight line from that point on his map to the coordinates given for his destination. That line gives him his base course, and using variables like the wind, ocean currents and estimated speed of the ship derives arrival time. If you read the orders sent out by Jellicoe to the fleet, he provides specific coordinates for the meeting point. I am certain Beatty's chief navigator took a reading on the point as they exited the port and used that his current position.
This type of navigation is actually titled orthodrome navigation used for long distance surface navigation whereas for very short distances, loxodrome navigation. Since the former cuts meridians at varying angles, you have to do constant course corrections to maintain the line. It's the combined use of both, that is actually at work. All this can be and is represented by the Mercator projection map used by navigators and familiar to almost everyone.
It was just a suggestion, to give the newbies some realism. Thanks for listening.
I to took a navigation course as part of my training a loooong time ago and all that you say is true, but surely the realism we are trying to recreate is the decision process at admiral (fleet, or squadron commander) level, this degree of detail is happening at navigation officer level. At fleet commander level the questions are more likely to be 'give me a course for Sunderland', 'set an intercept course for ...........', or clearing the smoke downrange, positioning for tactical advantage, visibility and sun effects, etc., it's not leaning over a Mercator Chart worrying about precise navigation and waypoints, you only have to get within sighting range of friendly, or enemy formations, to achieve your objectives. In 1912 the Titanic and various other vessels transmitted the position of the sinking, they were all wrong, some by several miles. Precise navigation comes into play when the fleet breaks up for entering an anchorage, etc., alternatively there's the BBC Navy Lark's immortal navigation technique of 'left hand down a bit'. Hi: I understand, my geography classes and my inertial navigation classes were a few moons ago, but as of late, since retiring I have tried to renew my knowledge. I agree that if you are the fleet commander, you might not be totally interested in the precise information about your course, but I am going to attempt to research in logs and personal accounts from the period. So, I am going to hold my opinion until I can get some confirmation. Interesting subject though.
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Post by Fredrik W on Dec 14, 2013 11:07:36 GMT -6
Yes, Rasputitsa, you are right, the precision is unnecessary for the simulation. It is just a nice side effect.
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Post by Rasputitsa on Dec 18, 2013 5:00:51 GMT -6
I to took a navigation course as part of my training a loooong time ago and all that you say is true, but surely the realism we are trying to recreate is the decision process at admiral (fleet, or squadron commander) level, this degree of detail is happening at navigation officer level. At fleet commander level the questions are more likely to be 'give me a course for Sunderland', 'set an intercept course for ...........', or clearing the smoke downrange, positioning for tactical advantage, visibility and sun effects, etc., it's not leaning over a Mercator Chart worrying about precise navigation and waypoints, you only have to get within sighting range of friendly, or enemy formations, to achieve your objectives. In 1912 the Titanic and various other vessels transmitted the position of the sinking, they were all wrong, some by several miles. Precise navigation comes into play when the fleet breaks up for entering an anchorage, etc., alternatively there's the BBC Navy Lark's immortal navigation technique of 'left hand down a bit'. Hi: I understand, my geography classes and my inertial navigation classes were a few moons ago, but as of late, since retiring I have tried to renew my knowledge. I agree that if you are the fleet commander, you might not be totally interested in the precise information about your course, but I am going to attempt to research in logs and personal accounts from the period. So, I am going to hold my opinion until I can get some confirmation. Interesting subject though.
Attached to help the research, Grand Fleet signal log for Jutland, probably not exhaustive and unfortunately not including the approach phase. Attachment DeletedWorth noting that the Grand Fleet was advancing on a visual warning frontage of 40 miles, from each wing of screening forces, reducing to 25 miles, as the visibility became worse. This is a bulldozer on the move and not a precision instrument, whilst on the 'Iron Duke' they were 4.75 miles ahead of their dead reckoning estimate, Beatty turned out to be 7 miles West of where Jellicoe had expected from reports. With the sound of gunfire audible and Beattie's battle cruisers reported in sight from 'Marlborough', from the extreme starboard column and knowing that the Highs Seas Fleet was closing from somewhere to the South, shell splashes from enemy fire visible around the BCs, what a situation to have to make critical decisions. Edit : I should have quoted the sources - The Great War at Sea 1914-1918 - Richard Hough, for the information in the text, the signals log came from an internet site.
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Post by oldpop2000 on Dec 18, 2013 8:13:52 GMT -6
Hi: I understand, my geography classes and my inertial navigation classes were a few moons ago, but as of late, since retiring I have tried to renew my knowledge. I agree that if you are the fleet commander, you might not be totally interested in the precise information about your course, but I am going to attempt to research in logs and personal accounts from the period. So, I am going to hold my opinion until I can get some confirmation. Interesting subject though.
Attached to help the research, Grand Fleet signal log for Jutland, probably not exhaustive and unfortunately not including the approach phase. Worth noting that the Grand Fleet was advancing on a visual warning frontage of 40 miles, from each wing of screening forces, reducing to 25 miles, as the visibility became worse. This is a bulldozer on the move and not a precision instrument, whilst on the 'Iron Duke' they were 4.75 miles ahead of their dead reckoning estimate, Beatty turned out to be 7 miles West of where Jellicoe had expected from reports. With the sound of gunfire audible and Beattie's battle cruisers reported in sight from 'Marlborough', from the extreme starboard column and knowing that the Highs Seas Fleet was closing from somewhere to the South, shell splashes from enemy fire visible around the BCs, what a situation to have to make critical decisions. Edit : I should have quoted the sources - The Great War at Sea 1914-1918 - Richard Hough, for the information in the text, the signals log came from an internet site. Interesting, that's what I haven't had time to find yet, but it does show that during communications, while the actual course is by compass points, he prefaces the course with exact lat-long readings for his location at that moment. It would appear to me, that precise navigation was a part of fleet commanders requirements. Do you agree? BTW, thanks for finding this, I will try to get some other information.
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Post by Rasputitsa on Dec 18, 2013 9:01:07 GMT -6
Attached to help the research, Grand Fleet signal log for Jutland, probably not exhaustive and unfortunately not including the approach phase. Worth noting that the Grand Fleet was advancing on a visual warning frontage of 40 miles, from each wing of screening forces, reducing to 25 miles, as the visibility became worse. This is a bulldozer on the move and not a precision instrument, whilst on the 'Iron Duke' they were 4.75 miles ahead of their dead reckoning estimate, Beatty turned out to be 7 miles West of where Jellicoe had expected from reports. With the sound of gunfire audible and Beattie's battle cruisers reported in sight from 'Marlborough', from the extreme starboard column and knowing that the Highs Seas Fleet was closing from somewhere to the South, shell splashes from enemy fire visible around the BCs, what a situation to have to make critical decisions. Edit : I should have quoted the sources - The Great War at Sea 1914-1918 - Richard Hough, for the information in the text, the signals log came from an internet site. Interesting, that's what I haven't had time to find yet, but it does show that during communications, while the actual course is by compass points, he prefaces the course with exact lat-long readings for his location at that moment. It would appear to me, that precise navigation was a part of fleet commanders requirements. Do you agree? BTW, thanks for finding this, I will try to get some other information. I feel that obviously precise navigation is the aim of all naval operations, but that in the circumstances of the time, precision was not possible and senior naval officers would know this. Setting a Lat/Long, or bearing and distance from a known point, would be ways of directing formations and formations were indicating their own positions and the positions of enemy forces in relation to their own declared position, or as bearing and distance from other units. Short answer is that the commander would want precise navigation, but be well aware that this was probably not possible, after long sailing distances, or during the maneuvers of combat. It was more like someone groping in the dark, with the screening forces being his outstretched hands. feeling for friendly and enemy formations. The above mentioned book (Kindle download, although now not free), recommended in another thread, gives a detailed description of the processes Jellicoe went through, before stepping to the compass platform and took 20 seconds of thought, before ordering the flag signal 'Equal Speed SE', confirmed by two short siren blasts, to hurry the deployment along. He made this decision without consulting his staff officers, there was no time for debate. AFAIK, without reference to a chart, he had calculated the probable position of the Highs Seas Fleet from previous reports, some garbled and incomplete (the actual position was only 2.75 miles out). He calculated an interception point, correcting for the errors that he had seen in particularly Beattie's reports. Beattie had been steaming hard and manouvreing greatly, so not surprising that the Battle Cruiser Fleet navigation and reporting was further adrift than the Grand Fleet. The Fleet Commander's requirement is to for his formations to comply as precisely as possible to his orders. Declaring a Lat/Long is the same as clicking the cross on the SAI map, meaning take me 'there', the detail of how it is done is not of immediate concern, that's for the enquiry if it goes wrong. An aside on log entries, Beattie's ships made a 160 degree turn, an order had been misunderstood and a turn started in the wrong direction, it was easier to continue through 160 degrees than the chaos that might have resulted in trying to reverse the turn. Beattie had the episode stricken from the log, in case it was said that he had turned away from the enemy, so you can't always believe what you read in the logs. There is obviously a place for precise navigation, but on the Admiral's Bridge it was purely assessment, judgement and decision by the man on the spot. von Scheer's decision process is even more chaotic, desperation leaves little room for precision.
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Post by oldpop2000 on Dec 18, 2013 9:19:54 GMT -6
Interesting, that's what I haven't had time to find yet, but it does show that during communications, while the actual course is by compass points, he prefaces the course with exact lat-long readings for his location at that moment. It would appear to me, that precise navigation was a part of fleet commanders requirements. Do you agree? BTW, thanks for finding this, I will try to get some other information. I feel that obviously precise navigation is the aim of all naval operations, but that in the circumstances of the time, precision was not possible and senior naval officers would know this. Setting a Lat/Long, or bearing and distance from a known point, would be ways of directing formations and formations were indicating their own positions and the positions of enemy forces in relation to their own declared position, or as bearing and distance from other units. Short answer is that the commander would want precise navigation, but be well aware that this was probably not possible, after long sailing distances, or during the maneuvers of combat. It was more like someone groping in the dark, with the screening forces being his outstretched hands. feeling for friendly and enemy formations. The above mentioned book, recommended in another thread, gives a detailed description of the processes Jellicoe went through, before stepping to the compass platform and took 20 seconds of thought, before ordering the flag signal 'Equal Speed SE', confirmed by two short siren blasts, to hurry the deployment along. He made this decision without consulting his staff officers, there was no time for debate. AFAIK, without reference to a chart, he had calculated the probable position of the Highs Seas Fleet from previous reports, some garbled and incomplete (the actual position was only 2.75 miles out). He calculated an interception point, correcting for the errors that he had seen in particularly Beattie's reports. Beattie had been steaming hard and manouvreing greatly, so not surprising that the Battle Cruiser Fleet navigation and reporting was further adrift than the Grand Fleet. There is obviously a place for precise navigation, but on the Admiral's Bridge it was purely assessment, judgement and decision by the man on the spot. von Scheer's decision process is even more chaotic, desperation leaves little room for precision. I wonder if we are discussing two different signaling concepts: maneuvering signals versus navigation signals. In that sense, you and the others are absolutely correct, the game is using maneuvering signals as a basis. However, Jellicoe mixes navigation signals with maneuvering signals in the log. I am really attempting to get my hands around this whole issue. It helps me to understand the game better.
archive.org/stream/battleofjutland300grearich#page/134/mode/2up
Take a look at this, its the official dispatches etc. from Jellicoe at Jutland, very interesting.
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Post by Rasputitsa on Dec 18, 2013 9:36:52 GMT -6
I have Jellicoe's own book, 'The Crisis of the Naval War' and von Sheer's book 'Germany's High Seas Fleet in the World War', with caution on reputation protection, I hope both will be enlightening. There are two different aspects to navigation, the Strategic, getting units to the desired location at the desired time, and Tactical manouvering in battle, but I would still hold to the view that the minutiae of navigation is not for the commander, enough to issue the order for others to implement. No more than stoking the boilers to achieve an ordered speed. Obviously the commander would be a highly experienced officer, well versed in the tasks of his subordinates, so as to know the realms of the possible, in keeping orders reasonable to execute. At least you would hope that to be the case.
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Post by oldpop2000 on Dec 18, 2013 9:56:58 GMT -6
I have Jellicoe's own book, 'The Crisis of the Naval War' and von Sheer's book 'Germany's High Seas Fleet in the World War', with caution on reputation protection, I hope both will be enlightening. There are two different aspects to navigation, the Strategic, getting units to the desired location at the desired time, and Tactical manouvering in battle, but I would still hold to the view that the minutiae of navigation is not for the commander, enough to issue the order for others to implement. No more than stoking the boilers to achieve an ordered speed. Obviously the commander would be a highly experienced officer, well versed in the tasks of his subordinates, so as to know the realms of the possible, in keeping orders reasonable to execute. At least you would hope that to be the case. I have those plus "The Grand Fleet,". There are others for free on Google Books if search for free books. Good discussion.
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Post by Rasputitsa on Dec 18, 2013 11:19:07 GMT -6
I feel that obviously precise navigation is the aim of all naval operations, but that in the circumstances of the time, precision was not possible and senior naval officers would know this. Setting a Lat/Long, or bearing and distance from a known point, would be ways of directing formations and formations were indicating their own positions and the positions of enemy forces in relation to their own declared position, or as bearing and distance from other units. Short answer is that the commander would want precise navigation, but be well aware that this was probably not possible, after long sailing distances, or during the maneuvers of combat. It was more like someone groping in the dark, with the screening forces being his outstretched hands. feeling for friendly and enemy formations. The above mentioned book, recommended in another thread, gives a detailed description of the processes Jellicoe went through, before stepping to the compass platform and took 20 seconds of thought, before ordering the flag signal 'Equal Speed SE', confirmed by two short siren blasts, to hurry the deployment along. He made this decision without consulting his staff officers, there was no time for debate. AFAIK, without reference to a chart, he had calculated the probable position of the Highs Seas Fleet from previous reports, some garbled and incomplete (the actual position was only 2.75 miles out). He calculated an interception point, correcting for the errors that he had seen in particularly Beattie's reports. Beattie had been steaming hard and manouvreing greatly, so not surprising that the Battle Cruiser Fleet navigation and reporting was further adrift than the Grand Fleet. There is obviously a place for precise navigation, but on the Admiral's Bridge it was purely assessment, judgement and decision by the man on the spot. von Scheer's decision process is even more chaotic, desperation leaves little room for precision. I wonder if we are discussing two different signaling concepts: maneuvering signals versus navigation signals. In that sense, you and the others are absolutely correct, the game is using maneuvering signals as a basis. However, Jellicoe mixes navigation signals with maneuvering signals in the log. I am really attempting to get my hands around this whole issue. It helps me to understand the game better.
archive.org/stream/battleofjutland300grearich#page/134/mode/2up
Take a look at this, its the official dispatches etc. from Jellicoe at Jutland, very interesting.
Looking at the dispatches, nice link, which are mostly concentrated on the battle itself, but the early references describe the C-i-C designating, by Lat/Long, rendezvous points for the components of the Fleet to combine and sweep the Eastern North Sea. This is to be expected and in the chart room of each vessel and principally the formation leaders, officers will be working with as much precision as possible to achieve the meeting. But, the admiral will have done his job in designating the co-ordinates, placing an X on the map and this is as far as SAI goes. The formations will route until within sighting range of friend, or enemy, and tactics will take over. With a visual frontage of 40 miles, I know this is the extreme case, but navigational error within 5 miles is good enough. It was the timing that became crucial, brought about by the variable visibility and the lateness of the hour, but this is the North Sea and perhaps the RN should have realised that there would be little chance to use the maximum range of the chosen bigger calibres. This was always likely to be a close-in brutal cat fight, but Jellicoe and Beattie had to fight with what they had and it is perhaps surprising that Beattie was surprised, that there was something wrong with his bloody ships. However, at great cost, Beattie had driven Hipper's group towards an Easterly course and delivered the High Seas fleet to Jellicoe, whose masterly disposition, even at the last moment, neatly completed the maneuver. von Sheer's worst nightmare was realised, confrontation with the whole Grand Fleet and slow pre-dreds in tow reducing fleet speed, he knew he had been very lucky. Anyway, it was a navigational success to bring it all together.
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Post by oldpop2000 on Dec 18, 2013 12:09:34 GMT -6
I wonder if we are discussing two different signaling concepts: maneuvering signals versus navigation signals. In that sense, you and the others are absolutely correct, the game is using maneuvering signals as a basis. However, Jellicoe mixes navigation signals with maneuvering signals in the log. I am really attempting to get my hands around this whole issue. It helps me to understand the game better.
archive.org/stream/battleofjutland300grearich#page/134/mode/2up
Take a look at this, its the official dispatches etc. from Jellicoe at Jutland, very interesting.
Looking at the dispatches, nice link, which are mostly concentrated on the battle itself, but the early references describe the C-i-C designating, by Lat/Long, rendezvous points for the components of the Fleet to combine and sweep the Eastern North Sea. This is to be expected and in the chart room of each vessel and principally the formation leaders, officers will be working with as much precision as possible to achieve the meeting. But, the admiral will have done his job in designating the co-ordinates, placing an X on the map and this is as far as SAI goes. The formations will route until within sighting range of friend, or enemy, and tactics will take over. With a visual frontage of 40 miles, I know this is the extreme case, but navigational error within 5 miles is good enough. It was the timing that became crucial, brought about by the variable visibility and the lateness of the hour, but this is the North Sea and perhaps the RN should have realised that there would be little chance to use the maximum range of the chosen bigger calibres. This was always likely to be a close-in brutal cat fight, but Jellicoe and Beattie had to fight with what they had and it is perhaps surprising that Beattie was surprised, that there was something wrong with his bloody ships. However, at great cost, Beattie had driven Hipper's group towards an Easterly course and delivered the High Seas fleet to Jellicoe, whose masterly disposition, even at the last moment, neatly completed the maneuver. von Sheer's worst nightmare was realised, confrontation with the whole Grand Fleet and slow pre-dreds in tow reducing fleet speed, he knew he had been very lucky. Anyway, it was a navigational success to bring it all together. I suspect that many of us didn't realize the difficulty of managing a fleet until SAI. While it is just a game, it is very engaging and accurate in its game play. Reading the dispatches and first hand accounts gives you the flavor, but SAI puts you in the drivers seat. This is the way I've always felt about air combat games, there is a difference in reading about it, than flying a simulator.
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Post by Rasputitsa on Dec 18, 2013 12:17:49 GMT -6
Looking at the dispatches, nice link, which are mostly concentrated on the battle itself, but the early references describe the C-i-C designating, by Lat/Long, rendezvous points for the components of the Fleet to combine and sweep the Eastern North Sea. This is to be expected and in the chart room of each vessel and principally the formation leaders, officers will be working with as much precision as possible to achieve the meeting. But, the admiral will have done his job in designating the co-ordinates, placing an X on the map and this is as far as SAI goes. The formations will route until within sighting range of friend, or enemy, and tactics will take over. With a visual frontage of 40 miles, I know this is the extreme case, but navigational error within 5 miles is good enough. It was the timing that became crucial, brought about by the variable visibility and the lateness of the hour, but this is the North Sea and perhaps the RN should have realised that there would be little chance to use the maximum range of the chosen bigger calibres. This was always likely to be a close-in brutal cat fight, but Jellicoe and Beattie had to fight with what they had and it is perhaps surprising that Beattie was surprised, that there was something wrong with his bloody ships. However, at great cost, Beattie had driven Hipper's group towards an Easterly course and delivered the High Seas fleet to Jellicoe, whose masterly disposition, even at the last moment, neatly completed the maneuver. von Sheer's worst nightmare was realised, confrontation with the whole Grand Fleet and slow pre-dreds in tow reducing fleet speed, he knew he had been very lucky. Anyway, it was a navigational success to bring it all together. I suspect that many of us didn't realize the difficulty of managing a fleet until SAI. While it is just a game, it is very engaging and accurate in its game play. Reading the dispatches and first hand accounts gives you the flavor, but SAI puts you in the drivers seat. This is the way I've always felt about air combat games, there is a difference in reading about it, than flying a simulator. Absolutely agree, have been looking for something like this since 'Grand Fleet' on the Atari. Battle Generator set to random, sighting report of unidentified ship, 'close, or not to close, that is the question'. This game is great.
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Post by oldpop2000 on Dec 18, 2013 13:07:51 GMT -6
I suspect that many of us didn't realize the difficulty of managing a fleet until SAI. While it is just a game, it is very engaging and accurate in its game play. Reading the dispatches and first hand accounts gives you the flavor, but SAI puts you in the drivers seat. This is the way I've always felt about air combat games, there is a difference in reading about it, than flying a simulator. Absolutely agree, have been looking for something like this since 'Grand Fleet' on the Atari. Battle Generator set to random, sighting report of unidentified ship, 'close, or not to close, that is the question'. This game is great. I just downloaded RJW so that's going to be fun. In the early 1970's, my friend and I used play a board game titled Jutland on the floor of the NCO barracks, it took the whole floor. I remember that was fun.
I am going to continue this discussion on the historical discussions of SAI of the history forum just to stay within the forum rules. See you over there.
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Post by williammiller on Dec 18, 2013 13:33:22 GMT -6
We are wandering off somewhat from SAI-specific subject matter here...please move the navigation/historical material to the General Discussion thread if you wish to continue with that part.
Thanks!
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