Naval mines in Command

December 16, 2016 · Posted in Mines, Uncategorized · Comment 

 

Image result for naval mineThere has been a question about Command’s mine warfare model on the forum so we would like to cover our mine model in more detail than the current manual covers.

To start it’s a good idea to have a little background on what naval mines are how they are detected and neutralized. If you’re not familiar there are some really great resources online that do a good job explaining the basics. Please do give these a good read if you’re unfamiliar with the concepts.

Now how does CMANO model mines, mine deployment, mine strikes, mine detection, and mine neutralization?

Mines in the database

CMANO eschews the traditional “minefield area with % chance to stumble on one” wargaming model and instead treats mines as discrete individual objects (yes, that means you can have thousands of them in a scenario. The sim engine can take it.). Let’s take a look at the general mine categories currently modelled in Command:

  • Bottom Mine. As the name implies, laid on the sea bottom. These are quite hard to pick on sonar and (if they are properly camouflaged) even with visual cameras. They can be used only in relatively shallow waters (if they are laid deep, when they detonate their explosive shock will dissipate until it reaches the surface).
  • Moored Mine. These are deliberately filled with some light material to provide them with positive buoyancy and then anchored to the bottom, suspended in mid-water. Because of this they can be laid in deeper waters than bottom mines. They are, however, easier to detect and neutralize.
  • Floating/drifting Mine. These float on the surface. They can be spotted and neutralized more easily than other types.
  • Moving/Mobile Mine. These are often converted torpedoes, fired from standoff range by ships or submarines, traversing a distance before settling on the bottom.
  • Rising Mine. These nasty weapons are either bottom-lying or moored, and instead of an explosive warhead their payload is a homing torpedo or rocket. When they detect a suitable target, the payload is launched and homes on the target independently.
  • Dummy mine. A fake mine, meant to delay counter-mine operations.

The mine attributes listed in the database include fuse types (magnetic, passive acoustic, pressure, seismic), arming delays, different warhead explosives and properties etc. Some of these attributes are not currently used (for example target discrimination is currently listed but not actually used in code) but have been included nevertheless for future revisions to the model. We’ve also provided generic examples of each major type in the database and in case where we’ve found detailed information on real life mines we’ve added them.

 

Deployment: Pre-fab and in-game

Mines can be deployed in any water area that meets the depth requirements for the mine. You can find these depth requirements in the database viewer or, if using the scenario editor to add a minefield, in the drop down select menu next to the mines name.

Mines are deployable in CMANO in two ways.

The first way is via the mining mission in the mission editor in either game or editor mode during gameplay by an air, sea or subsurface unit. You can create a mission by first defining an area by dropping some reference points, then selecting them and finally creating a Mining mission. This will open the mission editor allowing you to modify the mission parameters and if the mine type supports it an option to add arming delays for fields you want to activate later. Once a unit is assigned it will launch and drop mines about 400 meters apart in random lines dispersed in your defined area.

Here is an example of laying mines via a mission:

 

Things to note:

  • Multiple assets of different type can be used for the mining mission. In this example we are using the Iran Ajr in combination with a squadron of B-52Hs based at Bandar Abbas. (Yes, “Red” would not normally have access to B-52s but the Buff is as good a mining demonstrator as any. Cope!). To ensure the bombers have enough mines to sow, we are adding 10.000 Quickstrike mines to the base’s stocks. Submarines can also be used in the same manner.
  • One of the most useful custom options for the mining  mission is arming delay. This can range from 1 second up to years. This can help significantly in preventing the assigned forces from literally mining themselves into a corner. This can happen both in real life and in Command, but the delay option makes it far less likely. It also adds an extra element of uncertainty for third-party observers (“can I pass through that area before the mines are armed?”). In this example the delay is 1 hour, and every sown mine has a visible timer indicating the countdown to being armed.
  • The laying pattern is highly irregular and very rarely are 3 mines laid in a straight line. This is deliberate, as it prevents the enemy from discovering a few mines and then using their regular pattern to determine the locations of the rest. It does of course mean an uneven distribution of the mines and the possible presence of gaps in the coverage, but with enough density this is acceptable.

If you ever want to add a mine rack to a surface or submarine unit you can do so. We have added a number of mine rack type weapons records which you can add to any mount. Many combatants actually have mine racks in real life (Chinese FF, Soviet Destroyers) but aren’t filled or used unless specifically tasked.

The second way to deploy mines is there is a function in the game editor. To do so simply drop some reference points to define an area and select them. Next, go the editor dropdown menu, select minefields and then create minefields in designated area. A dialog will then appear allowing you to pick the mine you’d like and number. The editor will then do its best to randomly disperse mines in the area you’ve chosen with the correct depth requirements.

 

Going BOOM

Mine strikes are resolved in the game as follows. Once a ship or submarine reaches a certain distance from the mine a calculation is made to see if the mine is armed and triggered. If so then the mine explodes or the payload is released. If it is an explosion than our CEP modeled is leveraged and damage is applied accordingly. If it’s a payload the torpedo hit is calculated like any other torpedo and if it’s a rocket munition it will be resolved using CEP on its own. Keep in mind that any unit in range of the explosion could take damage. This includes mine hunting UUVs and RMVs that could be destroyed as well as minesweepers themselves. This could also occur during mine neutralization involving explosives or a failed attempt.

Here is an example:

 

A small USN amphibious group (an Essex LHD and a Mars replenishment ship, escorted by a Ticonderoga cruiser and a Burke destroyer) is about to enter the Hormuz straits in order to transit to the Persian Gulf. Unknown to them, we are laying a pre-made minefield using the scenario editor. We are laying approximately 500 mines, half of them moored and the other half floating ones. Despite stumbling on some of the mines and setting them off, the group crosses the minefield seemingly intact – however, close examination of the ships’ damage reports reveals that most of them have suffered substantial hull damage and many of their critical systems have been damaged or destroyed; the group is thus now a significantly easier target for follow-up attacks or may even have to abandon its mission altogether.

Several things to note:

  • Each mine category (and indeed in most cases each individual mine type) has its own operating depth restrictions. This, combined with the fact that most seabeds are non-uniform in their depth, means that laying a single-type minefield is frequently impractical. A multiple-type minefield is both easier to lay and tougher for an adversary to sweep.
  • Most modern mines follow a two-step arming & detonation logic: First the detection of an incoming valid target “wakes up” the mine, and only when the distance to the target opens (ie. the target is passing its nearest point relative to the mine, almost certainly beam-on) the warhead detonates. This protects the mine against simple “prodding” sweeps, retains the element of surprise and ensures the maximum damage to the target. Command models this faithfully.
  • If the mine happens to be right under the target, its destructive potential is magnified because of the “gas bubble” effect; under ideal circumstances the mine can even literally break the ship’s back  (similar to an under-keel torpedo detonation).

Mines are very cost-efficient and, if properly used, a tremendously effective naval weapon. It is illustrative that they have damaged and sunk more ships than any other weapon since WW2. So how does one counter them?

 

Detection

 

Mine detection varies based on the type of mine and technology used to detect them. Floating mines can be detected visually with the constraints of time of day and weather. All mines can be detected using mine hunting sonar. We do mark them as such within the database so you can use the database viewer to see what kind of sonar or gear a unit has. In general, bottom and moving mines are the most difficult to detect followed by floating and then moored and rising.

 

Sweeping

Sweeping is the most common countermeasure. Basically the sweeper is trying to prematurely trigger the mine so that it detonates (or releases its payload) while friendly forces are at a safe distance. Mine-sweeping gear is included under the sensor grouping in the CMANO database. All sonar detection is impacted by range of the unit and speed of the host unit and all mechanical gear is constrained by speed of the host vessel and usable depth of the equipment. Keep in mind all sweeping equipment has width, depth and speed constraints (ex. Mechanical sweep can sweep down to -70m to -10m at 8 knts.). If you zoom in on any unit with sweeping gear the sweeping arc is visible behind the unit.

Let’s look at an example of sweep operations:

 

“Red” has created a mine barrier on the entrance to the straits of Hormuz, and side “Blue” has to neutralize it by clearing at least part of it to create a safe transit lane. Blue has access to two Avenger-class and one Osprey-class mine-warfare ships (MCM), plus a dozen MH-53E Sea Dragon helicopters at nearby airfield “Base 1”, fitted with the Mk105 mine-countermeasures equipment.

First, we take a peek “behind the scenes” by briefly enabling “God’s Eye” view, to see what Blue is up against. The minefield looks pretty thick (around 3000-4000 mines). Normally Blue does not have access to this information.

Switching back to normal view, we define an area for the safe transit corridor we want to open. Using the created reference points, we create a new mine-clearing mission and assign all available assets to it, enabling the 1/3rd rule (more on this later). Then we sit back and watch them get to work: The ships activate their HF sonars and plot a course towards the area, and some of the helicopters begin their air ops procedures for taking off. This is going to take a while, so time acceleration is widely used.

Some observations:

  • Zooming on the MCM ships and helicopters shows their mine-sweep coverage (the blue triangles). Once one or more mines are detected, the vessels maneuver in such a way as to place the target mine inside this coverage area in order to trigger it. (The odds of this happening depend on the tech levels of the sweep gear and the mine being prodded; an old mine is much easier to sweep with modern equipment and vice-versa). If no mines are detected the units will still patrol inside the designated area, aiming to set-off undetected mines (hopefully without being damaged by them).
  • Helicopters are much more efficient than ships at sweeps against detected mines thanks to their speed (and reduced vulnerability) but are less effective at detecting the mines in the first place. Ships on the other hand have the sensors suitable for detecting mines en-masse but are less effective at clearing them, and more vulnerable. As is obvious in this example, ships and helicopters are most effective in this mission when cooperating to maximize their strengths.
  • All ships (including MCMs) try as much as possible to avoid passing too close to detected mines (the pathfinding code takes known mines into account when plotting a course). The “minimum safe distance” is estimated based on the ship’s own signature characteristics (magnetic, noise etc.) and whatever information is available about the mine contact. Smaller ships have a smaller keep-out distance and MCM ships have a big advantage thanks to their special signature-suppression techniques (non-metallic hulls & structure, enhanced degaussing, low-noise motors, reduced pressure etc.). This enables them to maneuver much closer to mines than other ship types in order to sweep or hunt them.
  • Despite these measures however, all 3 ships progressively suffer blast damage. (MCM vessels are designed with the assumption that they will suffer multiple proximity blasts during their lifetime, much more intense than for frontline warships). Even the best MCM ships are vulnerable to this; during the mine-clearing operations off Inchon in 1950, multiple MCM ships and destroyers were lost. Normally the ships withdraw after a certain damage threshold and return to a tender or naval base for repairs, rotating with others.
  • Midway through the operation one of the helicopters is destroyed by fragments from a surface mine detonation. This is not a bug; helicopters occasionally do get damaged or lost while detonating nearby mines (the USN lost two helicopters this way while clearing the Haiphong harbor in 1973). One of the upcoming new features of Command is gradual aircraft damage; this will enable sending the half-damaged helo home for repairs instead of permanently losing it.
  • At 8:53 we enter the mission editor and deactivate the mission’s “1/3rd rule”. This option dictates that hosted aircraft & ships will depart for their missions in 1/3 increments rather than all together, in order to rotate and thus provide continuous coverage of the patrol/mission area. Disabling this option allows us to perform a “surge”: All available assets tasked to the mission are immediately launched, providing temporarily a significant increase of on-station assets at the cost of reduced coverage in the long term. This is one of the typical trade-off decisions that the player must make.
  • Different sweeping gear types have different probabilities of setting off a given mine, based on the fuse type involved and the technological level. Old equipment can only get you so far!

Towards the end of the video, we pause the scenario and activate “God’s Eye” once more, to witness if the sweep team has made a difference. As can be seen, a very obvious dent has been made on the mine barrier; there is still much work, but the safe-transit corridor is beginning to take form. There is also something else noteworthy: Some mines close to the sweep team have not been detected at all. Such is the uncertain nature of mine operations.

This example was presented under favorable conditions for the sweep team: No unsweepable mines were included, and these do exist. Other mine types can be swept but are really hard to detect in the first place. Sweeping in general is efficient but bound to miss some here and there; a hard proposition for the forces that have to pass through the supposedly sanitized area. Thus sweeping is typically complemented by active mine-hunting operations.

 

Hunting

Compared to sweeps, hunting mines is extremely tedious and inefficient (it is sometimes described as the difference between using a lawnmower and cutting individual grass leaves one at a time); however, it is sometimes the only way to deal with sophisticated mines that ignore sweeping countermeasures.

CMANO includes a range of equipment types to neutralize mines in the game which gives players a range of options with different degrees of success. The equipment is deployed on traditional minelayers, aircraft, UUV, USV and RMVs and includes: divers with explosive charges; explosive charges hosted on units (killer type ROV/USV), moored mine and mechanical cable cutters (moored mine only) etc. Divers with explosive have the best probability of success, followed by explosive charges and all other equipment after.

Let’s look at an example mine-hunting operation:

 

In this video we present a typical mine-hunting scenario taking place inside the Persian Gulf. The Scout and Gladiator, two Avenger-class MCM vessels team up with The Sullivans, an Arleigh Burke-class destroyer and the Canadian frigate Halifax. The Avengers are the main mine-hunting force while the warships are screening them against any attacks. To hunt the mines, the Avengers are carrying SLQ-48 and Remus-600 tethered remote-operated vehicles (ROVs); these undertake the brunt of the mine neutralization process so that the ships stay (mostly) out of harm’s way. The Sullivans is also aiding the mine search by carrying and deploying a WLD-1 autonomous ROV.

At some point during the mine hunt, the force has to deal with some surprises. Things don’t always go as planned!

 

Delegating: The mine-clearing mission

CMANO provides a mine clearing mission within the mission editor. You create it by dropping some reference points, selecting them, selecting new mission from the Reference Point and Missions drop down and then add the units you’d like in the mission editor. The third rule is available for aircraft and ROVs. ROVs never appear in the mission editor but are added to the mission when their host unit is.

 

Hunting strategies

To effectively hunt mines in the game it is important to evaluate the constraints of the threat and the capabilities of your equipment.

The ocean is a big place and your ability to successful search any great swath of it for mines is pretty low even with the best gear. It is best to constrain your searches to areas that have the depth characteristics to contain mines and that the forces you are trying to protect might actually transit. Anything larger is a waste of time and resources. You may even consider rerouting transiting forces instead of trying to sweep lanes. It’s a strange game but the only winning move may be to not play.

Evaluating the mine hunting equipment you have is critical. Please do take a look at your order of battle and use the database viewer to see what units you have, the equipment they carry and evaluate their capabilities when developing a strategy.

Here are things we think you should consider and take note when make your decisions.

  • Traditional minesweeping ships are vulnerable even when successful at doing their job because depending on the size of a mine’s warhead it is likely the minesweeper will take points damage with any detonation from sweeping. We have coded in some things to reflect some of the design features to minimize this but it will happen and your ships have a limit as to how many close order detonations they can take.
  • Aircraft are preferable over ships because the likelihood of them being destroyed or damaged during sweeping is lower. Likewise UUV’s are somewhat more expendable and their losses hurt a little less than a mothership.
  • Many modern minesweepers act more as motherships for UUV or USV’s that sweep so it may be best to keep them out of the mine zones themselves thus only assign the UUV’s or aircraft to the mission.
  • Consider hunter-killer pairings. Aircraft and UUV/USV may have payload constraints so please review loads to make sure you actually have units that can detect and units that can kill mines. If it’s the case that a loadout can do one or the other please do assign both types.
  • Keep in mind the difference between a ROV and UUV. ROV equipment is tethered to the mothership. When a mothership is assigned to a mission all hosted ROV units will be assigned as well and launch once in the patrol zone or if a killer type once the mothership detects a mine. Keep in mind the tethers have a limited range which will constrain how far the ROV can travel from the mother ship and also means the mothership may have no choice but to move into the mined zone. On the other hand UUV and USV units are independent units that can be assigned directly to a mission within the mission editor. This is modeled this way to reflect their independent nature and lets the mothership standoff.
  • Do not create massive search areas when creating mine clearing missions. The patrol paths are random and the larger the area the more dispersed they are. Try to create search boxes smaller than 40 nautical miles (even smaller if just sweeping a lane) for best results and then create new ones or move the existing reference points to move ahead and shift the search area. If you don’t like a current plot you can just hit F3 for a new one.
  • If mines are smaller larger ships could be used to sweep with their own structures. You run an absolute risk of losing those ships but it’s a valid strategy that was utilized during the Iran/Iraq war.

Conclusion

We hope we’ve covered most of the basic questions about how the game models mine warfare and provided enough information for you to devise your own strategies. Please do feel free to contact us with any further questions!

New airborne mine-clearing system

July 5, 2009 · Posted in Blogroll, Uncategorized · 1 Comment 

ramics Wired’s Danger Room reports on a new airborne naval mine-clearance system being developed by Northrop Grumman. The system is based on a Seahawk helicopter firing high-speed underwater supercavitating projectiles:

Mounted on a helicopter, it combines a sensor to see through water with a 30mm cannon, which can take out a mine with a single shot.

The difference is in the ammunition. When a RAMICS round strikes the water, the pressure wave from blunt tip produces a bubble which surrounds the projectile. This reduces friction so, unlike other projectiles, the bullet keeps its velocity underwater.

A possible counter-torpedo role is also mentioned:

However, the success of RAMICS in tests suggests another alternative. If you can have a Phalanx gatling gun on the deck of a ship to defend against missiles, why not have something similar to destroy incoming torpedoes? RAMICS shows that it’s possible to detect a torpedo underwater using a laser-based sensor, and a 30mm supercavitating round which can destroy a mine can certainly destroy a smaller, think-skinned torpedo. The main question would be accuracy – but RAMICS has proved more accurate than expected in tests, and only needs one shot.

In fact, this is exactly the approach taken by Darpa’s Very High Speed Torpedo Defense project. Testing of the sensor, targeting mechanism and projectiles are being carried out this year in a variety of sea states. (Elsewhere, it’s been suggested that an underwater gun pod, firing supercavitating rounds may be used rather than one above the water).