THE DETAILS BEHIND THE ATTACK ON THE TIRPITZ I refer to the last 4 pages of the REVIEW for April 1990, in which my creative cardboard simulator of midget submarines was headed "Sink the Tirpitz". I must protest that this is inaccurate, since the game was actually entitled "The Beni Ngoma Game". In case your readers do not immediately recognize this reference, I should explain that in the 1920's, the East African Beni Ngoma tribe designed and built a number of cardboard battleships, cruisers, destroyers, etc., and paraded them through the streets on motorised floats. The officers - wearing Royal Navy style uniforms - stood on the "bridge" drinking pink gins, since this practice was deemed to be the ultimate essence of modern naval warfare. Thus the Beni Ngoma publicly showed themselves to be every bit as good as the RN... and in our own game, I would claim that we did this, too. I must also protest that your -description of the game, while splendidly evocative and entertaining to read, sadly lacked many of the technical details that might have allowed your subscribers to recreate the midget submarine simulator in the comfort (and secrecy!) of their own homes. Readers obviously spotted that this was a problem, since they have already forced you to explain that I have not, in fact, cut a hole in the middle of my dining room table (REVIEW for May, 1990, Pg 1). However, I feel that your readers also have a right to read about some of the other technical solutions that we reached within the X-15. In the first place, the navigator obviously didn't understand about the engines. There were, in fact, two of these, not one: a main (diesel) engine for use when the X Craft is running on the surface, and secondary (electric) engine for submerged action. A sliding cardboard indicator allowed the crew to select their depth and repeat this information to the umpire. Possible depths were: surfaced, periscope depth, 100 feet, 200 feet, or 300 feet (the deeper you are, the safer you are from depth charges, but if you're surfaced in daylight, you can be seen by the enemy, which is VERY DANGEROUS). tactics are determined by the dangers of running on the surface in daylight, and the fact that the electric engine's batteries must be recharged every so often by running the diesel, i.e., it is best to surface at night, but submerge during the day. The air compressor must be used when surfaced, otherwise the submerged craft will run out of air and the crew become "woozy". Another important point is that the crew received a map that had no hexes marked on it, whereas the umpire had a stylized "hex" map (taken from my A BOOK OF SANDHURST WARGAMES, published in 1982). The X Craft started at the center of a particular hex, then progressed in each "move" or "turn" to the center of a contiguous hex. A submerged turn took longer in game time than a surfaced turn - so to that extent we were using "variable bounds" - but each type of turn was resolved in the same amount of real time. My method of plotting the progress of the X Craft was to allow it only six possible rudder settings (shown on a sliding cardboard marker that was calibrated twice... i.e., repeating the selected direction both to the crew inside the sub and to the umpire outside). The setting selected by the crew determined which of the six sides of the hex the sub would exit. If the selected direction led to a fjord wall, one of two types of warning would be issued. A surfaced sub would be shown a picture of a looming cliff on the "dead ahead" face of its hexagonal "periscope"; a submerged sub would see only f ish in its perisope, but would hear scraping noises along its keel. If the sub heeded these warnings, it would veer away and exit some other hex side, but if it took no notice, it would crash into the rocks and sink. The compass should also be explained. This was a large circular dish with compass points marked on it. Half the dish lay outside the X Craft, and was moved around by the umpire every time the sub changed direction (the players were not told there were only six possible settings). The other half of the compass was inside the sub, where the navigator could read it off and work out the direction being sailed. The umpire had pre-ordained details of what the Germans were up to. Thus the anti-submarine booms and nets were marked on the master map (but not all of them were shown on the players' map), as were the patrol patterns of defending destroyers. When a German destroyer came into the same hex as the X Craft, the latter would see it in the periscope and hear the "pinging" of Sonar. Depending on the countermeasures taken by the sub, the Germans would get more or less chances to drop depth charges. Also, the die rolls needed to score a hit would be modified. In each attack, there would be a chance of sinking the sub - but the deeper it went and the longer it stayed down, the smaller chance there would be for it to be sunk. As for the Tirpitz herself, she is pre-programmed to stay at her moorings unless and until she gets wind of a midget submarine attack, one hour after which she will move to the open sea. She can get wind of an attack in two ways... either the played X Craft is seen on the surface by a German unit within 10 miles of Tirpitz, or one of the other five (unplayed) X Craft reveals itself according to its unpire pre-programming. In Wally's game, one of the unplayed X Craft attacked another ship near Tirpitz just as the played X Craft was dropping its charges. This compromised the attack on the Tirpitz herself -- so Wally should have made his attack a couple of hours earlier! And a final note by your friendly editor... So help me, I wasn't aware of half the things revealed above by the good Dr. Griffith! I must have been sleeping during the pre-game briefing... or better yet, since I was the X-Craft's navigator, I probably was studiously reviewing my deep water charts, anxious to get the show on the road. Back to PW Review June 1990 Table of Contents Back to PW Review List of Issues Back to MagWeb Master Magazine List © Copyright 1990 Wally Simon This article appears in MagWeb (Magazine Web) on the Internet World Wide Web. Other articles from military history and related magazines are available at http://www.magweb.com