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Silent Hunter:

Reality While on Patrol

One of the common discussions in our community is how to make patrols and patrol results more realistic.


Silent Hunter has a number of features to help in this area but in the end it is still a game. The primary Game feature that makes patrol's less realistic is the over abundance of targets. The second and the subject of much debate is the use of the Automated TDC. In the following paragraphs I will try to present some ideas on how to get more realism into the Patrol.

As a PTC Commander you will be playing the game at somewhere between 95% and 115% realism. Depending on if you choose Advanced or Expert level and the use of the depth gauge. How you operate determines how real the results will be.


The first item to implement for a realistic patrol is a "real" patrol plan. The basic submarine patrol in WWII consisted of searching in the assigned zone trying to determine where the Jap's were sending their convoys. Then waiting for a contact. This can be emulated in Silent Hunter by setting up a patrol route, generally crisscrossing a known convoy route, on the map screen and waiting for a contact. Another common patrol technique would be to stay in deep water during the day. Surface at dusk, charge the batteries and run in close to shore, or off a port, where you expect the enemy convoy's to be, depart before dawn for the deeper water.

During the day the submarine should be submerged, in areas were enemy patrol planes, i.e., your patrol zone, may be encountered. It is recommended that a depth of 200 feet or greater be used to avoid detection from aircraft. On a regular basis you should come up to periscope depth, or a little less to take a look around. Cruising should be at 1/3 speed to save the battery and give better sound detection. At times you can stop the engines to improve the sound range but keep some headway in order to maintain stability of the boat. Once you have radar you can take radar sweeps but it probably isn't wise to sit at radar depth all day. It's possible that the radar can lead the Jap's right to you.

After an engagement change your area of operation within the zone. The Jap's will know where you are and either send ASW forces to find you, route convoys around you or probably both.


The next degree of difficulty is the Manual versus Automated TDC usage. Although I will not go into the details of Manual TDC operation and approach techniques there are some great documentation and tools available from Kim Ronhoff and articles by Frank Kulick discussing this subject in great detail. Suffice to say that when using Manual TDC the Commander determines the settings to key into the TDC and manually keys in the entries, in effect you're the TDC operator, as well as CO, plotting party, etc. The quality of your entries determines the quality of the torpedo firing solution. Garbage In and one or more $60,000 torpedoes sail off into the sunset. I have found with a little practice Manual TDC can be more accurate than AUTO TDC which has built in inaccuracy factors. The cost to the player is much more work and time spent during an attack.

However in my opinion Manual TDC is a technique all COs should be capable of using since it allows you to setup the TDC early on radar contacts. In a pinch it also lets you fire torpedoes based on sound contacts. In a recent game I was surrounded by 9 destroyers. I wasn't able to shake them so after they made a pass I lined up the group off the stern where I had four torpedoes ready. Switched TDC to manual, keyed in bearing 180, coming in my direction, speed 0.1 knot range 2000 yards. Hit the red button and the TDC calculated the solution of a 0 track and ready to fire. Fired one at 0 offset, one at 3 left, one at 3 right and the last one minute later one at 10 right, as the formation was condensed to that side of us. Came to 1/3 speed. Registered one hit but I'm sure the force took evasive action and or chased the torpedo screws or explosions at end of run. Contact was broken and we escaped.

As early as WWI the US Submarine force adopted a separation of duties plan during a torpedo attack. Doctrine called for the CO to be at the scope viewing the situation while others did the math and plotting for the attack relaying the appropriate info back to the CO. In WWII some COs, following Mush Morton's lead, adopted a stance of having the XO, or officer with the best night vision, at the scope. This left the CO free to view the Plot, TDC and generally be apprised of and in control of the entire situation.


One of the major drawbacks I find in the Silent Hunter Auto TDC, versus a real plotting team, is that the target must be in sight for the Auto TDC to function. The solution is lost if the periscope is lowered.

To increase reality, and keep the scope out of sight I do the following. Take a reading on the Target using Auto TDC. This enters all of the appropriate data for you automatically, i.e., the following conversation: "Up scope, WHIRRRRR, Bearing Mark, 310, Range Mark, 3500, AOB port 30, Down Scope, WHIRRRR." Then with the scope out of sight you can tell the plotting party all the particulars. "Target has zigged to starboard, wait till he settles on new course. Escort at 1500 yards will pass well clear." You can see that on the chart screen with the scope down.

To do this in Silent Hunter just switch to Manual TDC before dropping the scope. This lets the TDC crank with the latest data without you having to manually key the TDC and do the distance / AOB / Target course estimates yourself. Thirty seconds later during the approach Scope Up "F2", Switch to Auto-TDC for an updated entry into the TDC, Manual TDC, "F5" to view the chart screen and get an up to date overall view of the situation, then scope down "ALT-P." This operation is much more like a real world approach. You can change the target selected in the TDC when in AUTO mode by double clicking on the ship on the chart screen.

When ready to Fire take your final Auto TDC reading, drop the scope and fire from the TDC at 8 second intervals without raising the scope or updating the solution between shots.

You can control the spread using the dial on the TDC. Generally I fire first at MOT, offset 0, second to lead the target, i.e., bow or forward goal post, third a little behind, i.e., wheel house or stern. Early in the War if using only two torpedoes drop the MOT.

If you don't feel comfortable with your ability to convert degrees to spread distance at the target's range calculation do the following. Keep the scope up while shooting, aim the red indicator at the desired point of impact on the target, BOW, MOT, or STERN, leave TDC in MANUAL, HIT the SPACE BAR, a new bearing is keyed into the TDC for you (Bearing Mark). The solution light will go out. Click the red solution light. The TDC calculates new solution using newly input bearing. FIRE, set in second point of AIM in the same manner and FIRE. You can also lead or trail the actual target using this method. So for a Large Target fire first at the Bow, second at the Stern, third to pass just behind, fourth to pass just ahead and fifth at MOT to maximize potential hits versus errors in solution / evasive action. If he is slow or turns away 2, 3 and 5 should hit. If he's fast or turns toward, 1, 4 and 5 should hit. If he's asleep, takes no evasive action, and at the right speed 1, 2, possibly 3 if he slows down quickly, and 5 should hit.

Copyright © 2006 by Ray McNeice. Used with the author's permission.