Tag Archives: MCM

The Number of Mines is Less Than Infinity

By Dr. Michael M. Rosenthal, Naval Surface Warfare Center, Panama City Division

“I would be very surprised if professionals engaged full time in [Mine countermeasures] MCM who speak routinely with other professionals in the same field had no genuine prior knowledge.”–Fred Huffer, Professor of Statistics, Florida State University

Mine countermeasures are actions intended to reduce the risk that mines pose to transiting vessels. Risk is defined as the probability that a transiting vessel will incur mission abort damage from a mine detonation if it travels along a predetermined route through the potentially mined area. The purpose of an MCM operation is to lower the risk so it is safer to transit. The estimation of risk is critically important to determine if the level of risk to a transiting vessel is acceptable and if the applied effort is effectively lowering the risk.

Some of the traditional MCM tactics are founded on Bayesian risk metrics that utilize a non-informative prior distribution for the number of mines. Some statisticians prefer to use non-informative priors because they feel it is more objective. The non-informative prior reduces the amount of required inputs from the tactician so there is less error introduced from the human operator, but it also defeats the entire purpose of using a Bayesian paradigm because the prior distribution does not utilize any information. It assumes that any number of mines is equally likely. In most cases, it is far more likely that there are just a few mines and it is very unlikely there are millions of mines.

Bayesian methods are ideal for the development of MCM risk metrics because they facilitate learning as information is acquired. This is good for MCM because new information and new decisions are frequently acquired throughout the operation. New events often occur which provide critical information and appropriate responses are promptly needed. These events vary greatly in detail. Bayesian analysis centers on utilizing Baye’s theorem to formally combine prior information with newly gathered information. This provides more freedom to create information synergy. 

Bayesian calculations utilize a prior distribution to incorporate information about parameters of interest before conducting a trial. In the context of MCM, the total number of mines is an unknown parameter of interest and a search or sweep of the mines is a trial. The choice in prior distribution is less critical when data is plentiful as long as the prior is not too restrictive. When there is an abundance of data, a reasonable prior will have a weaker impact on the final analysis because the posterior distribution will be primarily influenced by the data. However, data is usually limited in MCM operations, so the prior distribution will have a stronger impact on the analysis. In this case, it is critical to scrutinize the choice of prior in order for the risk metric to be meaningful.

Some of the traditional risk models actually use an improper prior for the total number of mines. An improper prior is sometimes used as an uninformative prior with the interpretation that any value is equally likely. However, many statisticians caution against using them since they are known to complicate interpretation and this usually does not provide an appropriate Bayesian update. The improper prior is formed by taking a limit of uniform distributions as the maximum number of possible mines goes to infinity. This does not converge to a probability distribution, so there is no meaningful interpretation of the prior belief for the number of mines.

Having an appropriate Bayesian update is important to MCM because if the result of a single pass of an MCM clearance does not reduce the posterior risk to an acceptable level, then the MCM staff will need to re-plan and execute a second clearance operation in the same area to further reduce the risk. This process will iterate until the risk is lowered to the threshold level.

As Fred Huffer stated, “It would be very surprising if professionals engaged full time in [Mine countermeasures] MCM who speak routinely with other professionals in the same field had no genuine prior knowledge.” If the user cannot reliably provide any information, then a large value for the expected number of mines and a corresponding large variance can be chosen because there is less certainty in that estimate. The user should be able to reliably provide some basic information that can be utilized in the prior belief by answering two simple questions:

  • How many mines could be in the region (few or many)?
    • (Few) i. e. the enemy has a small inventory or just a few can fit in the region
    • (Many) i. e. the enemy has a large inventory or they could lay thousands in the region
  • How certain are you in the amount above (low or high)?
    • (Low) a subjective guess based on limited intelligence information
      • i. e. if I were a minelayer, what would I do?
    • (High) a more objective belief based on concrete observations.
      • e. g. vessel with room for 10 mines was sighted laying mines.

The negative binomial distribution is one possible prior distribution that can be used for the mine risk Bayesian framework. Analytical expressions for the required clearance and the risk from remaining mines are easily derived. Not only is the mathematics cleaner and easier to interpret, but it also provides a sensible approach to incorporate prior intelligence information (information known before applying effort) into the analysis.

How does using the negative binomial distribution compare with the popular (uninformative) improper prior? There is no significant difference between calculations derived using the improper prior and using a negative binomial distribution with mean of 10^15 and a variance of 10^30+10^15 as the prior distribution. This default distribution implies that on average we expect there to be one quadrillion mines in the region with an unthinkably enormous variance (one nonillion + one quadrillion) to adequately accommodate our complete uncertainty in the possible number of mines prior to applying effort. To put these numbers into perspective, the surface of the ocean has an area of roughly 360 million square kilometers. That is 3.6×10^14 square meters. If you could place one quadrillion mines over a 360 million square kilometer area, the mines could be spaced on a rectangular grid roughly 0.6 meters meters apart. This setting of the prior goes as far as to say that we think it is reasonably possible that there could more than two quadrillion mines in the region.

If there is genuine concern that the end user cannot do better than this assumption, then after applying mine countermeasures a simple hypothesis test can be done to validate the user selected prior mean and variance against the default. In this way, if the end user significantly mis-specified the prior, then a flag can be automatically raised to warn the commander that the user is unable to translate the prior intelligence information into a reasonable prior belief for this operation. In this case, the command will have significant evidence to reject the assumption that a more reasonable prior belief can be derived by the end user, and return to the default condition. It is important to note that such a flag raise would not imply an outrageous deficiency in judgement by the end user. However, a flag-raise should initiate a discussion of caution toward objectively and consistently arriving at a reasonable prior distribution. Following this protocol should effectively insulate the MCM mission from this type of human error.

We generally prefer to make decisions based on an analysis that utilizes more information over a similar analysis which utilizes less information. An analysis that relies on a non-informative prior can most often be improved with an informative prior. With a non-informative prior, no prior information is being specified, so it is easy to come up with a distribution that utilizes some additional information. An informative prior often improves the interpretation and practicality of the analysis because more realistic assumptions can be made.

The updated theory in this work gently bridges more traditional doctrine into a broader realm of possibilities so that some basic information that has not been utilized can now be incorporated to improve the decision quality for the Navy.

Dr. Michael Rosenthal received his doctorate degree in Mathematical Statistics from the Florida State University in 2014. He received his bachelor’s degree in Mathematics with a minor in Statistics from the University of Florida in 2009. For five years, Dr. Rosenthal has worked at the Naval Surface Warfare Center, Panama City Division, developing basic research topics with academic colleges and assessing warfighter needs for updating and transitioning actionable tactics in the field of mine warfare.

Featured Image: BALTIC SEA (June 18, 2019) HDMS MSF-1 assigned to Standing NATO Mine Countermeasures Group One (SNMCMG1) conducts side scan sonar exercises while transiting the Baltic Sea during exercise Baltic Operations (BALTOPS) 2019. (U.S. Navy photo courtesy of NATO by CPO Brian Djurslev/Released)

The U.S. Navy Needs AWNIS for Mine Warfare

Mine Warfare Topic Week

By LT Colin Barnard, USN

Earlier this year, General Scapparotti, former Commander of U.S. European Command and Supreme Allied Commander Europe of NATO forces, sounded the call for a greater U.S. Navy presence in the Euro-Atlantic region to counter Russian aggression. The U.S. Navy has been increasing its presence in the region since Russia’s illegal annexation of Crimea in 2014, most notably conducting patrols in the Baltic and Black Seas. More recently, the U.S. Navy reestablished U.S. Second Fleet in Norfolk, Virginia, the commander of which will also head NATO’s new Joint Force Command in the same location, and is providing the flagship for Standing NATO Maritime Group 1 for all of 2019, one of four groups that make up NATO’s Standing Naval Forces.

Despite these increases, General Scapparotti was correct to say that an even greater U.S. Navy presence in the region is needed. However, greater U.S. Navy presence in Europe means greater involvement in NATO; and greater involvement in NATO requires greater use of NATO doctrine, some of which is not currently practiced by the U.S. Navy.

One such doctrine is the Allied Worldwide Navigational Information System, or AWNIS, which is crucial for conducting military operations at sea, especially mine warfare, while minimizing disruption to merchant shipping. This crucial doctrine can help modify and reroute sea lines of communications as they become threatened and endure combat operations. But unfortunately, the U.S. Navy knows very little about this system, its processes, or its merits.


AWNIS is not a technical system but rather “instructions for the promulgation of navigational dangers during times of war,” as the first NATO Military Committee document described it in 1952. AWNIS is necessary to conduct operations at sea while minimizing disruption to the maritime domain because it provides the procedures to promulgate Safety and Security of Navigation (SASON) information on navigation hazards that result from military operations—e.g. sea mines—fulfilling legal obligations specified in international humanitarian law and conventions such as Safety of Life at Sea (SOLAS).

To accomplish this, AWNIS collates inputs from tactical units—e.g. mine countermeasure (MCM) forces—then disseminates the information to merchant and military ships based on classification level. To promulgate the information to merchant ships, AWNIS uses the existing civilian Worldwide Navigation Warning System (WWNWS) architecture to transmit Navigation Warnings (NAVWARNs). To promulgate the information to military ships, AWNIS uses the Q-Message system. More information on AWNIS processes can be found in the primary AWNIS publication, Allied Hydrographic Publication 01 (AHP-01). The Q-message system is specified in a classified supplement to AHP-01.

AWNIS’ Origins

The British Royal Navy, in conjunction with what is now called the U.K. Hydrographic Office (UKHO), developed the AWNIS doctrine in response to lessons learned during WWI and WWII. During WWI, Central Powers sank more than 5,000 allied and neutral merchant ships in the North Atlantic Ocean with projectiles, torpedoes, and mines, creating navigational dangers for all seagoing vessels, including submarines. However, there was no procedure in any navy at the time to track the shipwrecks and sea mines, or disseminate their locations while taking into account operational security. Additionally, mine clearance and salvage operations take time, as do chart corrections.

Without a procedure in the military to identify and share information about navigational hazards during the war, civilian institutions had to locate and mitigate these hazards when the war ended. To this day, shipwrecks from the wars of the 20th century and, more dangerously, sea mines, are still being discovered in the waters around Europe. Germany placed over 40,000 mines around the British Isles during WWI alone. A key part of the AWNIS doctrine is post-conflict stabilization, which ensures all hazards to navigation that emerge during a conflict are tracked, then declassified and shared with civilian institutions to ensure restoration after the conflict is over.

AWNIS and Mine Warfare

In NATO, the AWNIS doctrine facilitates Mine Danger Areas (MDAs) and Q-Routes, in addition to other threats to safety and security of navigation. AWNIS Officers embarked with MCM forces draft MDA requests to the AWNIS lead, known as the Safety of Navigation Information Coordinator (SONIC), who is co-located with the MDA establishing authority, usually the Maritime Component Commander.

While it is crucial that MDAs be reported to all friendly naval forces, this detailed information is classified and cannot be shared with merchant shipping. If merchant shipping were told where MDAs are established, the enemy responsible for laying the mines would know which mines have been found. Thus, the details of an MDA are classified and distributed via the Q-Message system only. To fulfill the legal obligation to inform merchant shipping of the mine threat, NAVWARNs are used to establish Areas Dangerous to Shipping (ADS), which can cover a wider area than actually affected in order to maximize the safety of the merchant mariner and, ideally, freedom of maneuver for naval forces. Similar to a Maritime Exclusion Zone, which is also established by NAVWARN, an ADS should be carefully planned in order to ensure the least disruption to the maritime domain. Another doctrine exists in NATO and works closely with AWNIS in this effort—Naval Cooperation and Guidance for Shipping (NCAGS).


More than 50,000 merchant ships sail the world’s oceans, carrying more than 90 percent of the world’s trade. Conversely, only 1,500 warships sail the world’s oceans, of which approximately 200 are at sea at any given time, the rest remaining in port for maintenance and training. While vastly outnumbered, what warships do at sea can greatly affect merchant shipping, potentially disrupting its free movement and thus the global economy. AWNIS and NCAGS work in concert to reduce this potentiality.

While the AWNIS doctrine is responsible for managing the environment on which both military and merchant ships sail, the NCAGS doctrine provides the procedures for military forces to cooperate with and guide merchant shipping, effectively assisting shipping to travel from point A to B safely, i.e. freedom of navigation. This can be accomplished using basic routing guidance like Sailing Information, or through more tactical measures like group transit and lead-through operations. NCAGS relies on the AWNIS overview of the environment to accomplish this task. In the event of lead-through operations, NCAGS also relies on Q-Routes, which are pre-planned channels and routes surveyed during peacetime. Utilizing the Q-Message system, Q-Routes are activated as needed to ensure access to ports or other areas of operational importance for military and merchant ships.

AWNIS and SLOC Protection

In addition to closely cooperating with mine warfare and NCAGS, AWNIS also collates information necessary for the Maritime Component Commander to efficiently position assets to protect sea lines of communication (SLOCs). When navigational hazards like minefields and shipwrecks caused by mines, torpedoes, or missiles are plotted, the Maritime Component Commander is able to visualize the battlespace and the threats to SLOCs. Overlay the operational intelligence picture of the adversary’s naval and anti-access capabilities, especially coastal missiles, and the picture becomes mostly complete.

NCAGS officers have the means to recommend routes for both merchant shipping and strategic sealift around these threats, effectively establishing a SLOC. This also aids in the deconfliction of military activity from merchant shipping. For example, during a scenario in which merchant ships must sail from the U.K. to Norway during a major conflict, NCAGS would rely on AWNIS to show where all recent missile and mine strikes have occurred at sea or in ports, all MDAs, and activated Q-Routes in order to accurately advise the ships where to sail. NCAGS officers deployed in ports or on merchant vessels would be used to communicate sensitive information such as the details of a Q-Route.

AWNIS and Hybrid Warfare

The AWNIS doctrine is increasingly relevant in the context of an aggressive Russia that is openly challenging the laws of the sea through hybrid maritime activity. In November 2018, Russia closed the Kerch Strait to innocent passage, first by promulgating a false NAVWARN, then by placing a merchant vessel under the Crimean Bridge to block the strait. More recently, Russia has been promulgating NAVWARNs for naval exercises in the Black Sea that cover larger areas than necessary, seemingly with the intent of disrupting freedom of navigation. In most cases, the Russian Federation Navy (RFN) does not fully use these exercise areas.

While the RFN is ultimately responsible for the safety of merchant vessels passing in or near these exercise areas, accidents are possible. Even worse, it is difficult to foresee how the international community would respond to such an accident, especially if there were indications the accident was intentional, e.g. to disrupt the passage of a merchant vessel bound for a Ukrainian port. Regardless, as long as Russia continues to abuse the international systems in place for disseminating SASON information, the international shipping community would be right to distrust information promulgated by and for the RFN. Conversely, the U.S. Navy and NATO need to take care to always use these systems correctly, which the AWNIS doctrine seeks to ensure. In peacetime, crisis, and conflict, the U.S. Navy and NATO stand ready to be recognized as trusted brokers of SASON information.

Practicing the AWNIS Doctrine

The U.S. Navy should look to other NATO navies in order to establish AWNIS expertise for its own purposes. The already well-established U.S. Navy NCAGS community, part of the Reserve Component, should become the primary AWNIS expertise for the U.S. Navy. This is how the navies of the U.K., Norway, the Netherlands, and Belgium manage the system. As AWNIS and NCAGS are inseparable in practice, the majority of reserve officers with warfare backgrounds in the U.S. Navy NCAGS community should be trained in both. From this new U.S. Navy AWNIS and NCAGS community, every numbered fleet commander should be assigned a Staff AWNIS and NCAGS Officer, acting as the principal adviser on SASON and ready to act as the SONIC in the event of an operation. If MCM forces are involved, reserve officers should be ready to support them with AWNIS expertise.

The central location for AWNIS and NCAGS expertise in NATO is the NATO Shipping Centre (NSC), part of NATO Maritime Command in Northwood, U.K. Though tasked with wider maritime situational awareness responsibilities, the NSC should play a role in establishing AWNIS expertise in the U.S. Navy, bearing in mind that AWNIS is not only relevant to the littorals of Europe. The mine threat is equally existential, if not more so, in the Strait of Hormuz and Taiwan Strait.

With the AWNIS organization in place, military units at sea and merchant shipping could be confident in the U.S. Navy’s ability to manage SASON information during crisis or conflict. More importantly, the Joint Force Commander could be confident in the Maritime Component Commander’s ability to protect SLOCs and help both merchant shipping and strategic sealift make it to their destination, whether to support the civilian population or the Land Component Commander.

AWNIS is not the only NATO doctrine the U.S. Navy needs to practice, but it is fundamental. No longer can the crew of a destroyer wait until they “chop” under NATO operational control to dust off the NATO publications on the back shelf. As recently argued by VADM Lindsey and members of his staff at NATO’s Combined Joint Operations from the Sea Center of Excellence (CJOS-COE), U.S. Navy knowledge gaps in NATO doctrine need to be identified and filled to ensure successful integration and interoperability with NATO forces. The U.S. Navy’s mine warfare community is already ahead of other warfare communities in this endeavor, through participation in NATO exercises like DYNAMIC MOVE. Adopting AWNIS is a natural next step.

Lieutenant Barnard is serving as a staff operations and plans officer at NATO Maritime Command in Northwood, U.K. He was previously gunnery officer onboard USS ARLEIGH BURKE (DDG 51) and weapons officer onboard USS FIREBOLT (PC 10), and he was recently selected to be a foreign area officer in Europe. He graduated from the University of St. Andrews in Scotland with a master’s in terrorism studies and holds a bachelor’s in political science from Abilene Christian University in Texas. His views are his own and do not represent the views of the U.S. Navy or Department of Defense.

Featured Image: HMCS St. John’s performs manoeuvres with other members of Standing NATO Maritime Group One while on Op REASSURANCE in the Baltic Sea, March 21, 2018. (Photo: CPL TONY CHAND, FIS)

Call for Articles: PEO USC Launches CIMSEC Mine Countermeasures Topic Week

Submissions Due: October 14, 2019
Week Dates: October 21-25, 2019
Article Length: 1000-3500 words
Submit to: Content@cimsec.org

By Dr. Sam Taylor, Senior Leader, Mine Warfare
Program Executive Office, Unmanned and Small Combatants (PEO USC)

Naval experts almost universally agree that conducting effective mine countermeasures (MCM) is one of the most difficult and time-consuming missions for navies to successfully execute. Mines come in many different and increasingly deadly types, and can be deployed in deep or shallow waters, and in the surf zone. The bottom clutter and the dark, turbid ocean environment effectively helps to hide them from easy detection.

While difficult to undertake and execute well under demanding operational conditions, achieving success in the MCM world is not a mission impossible. For the U.S. Navy, MCM has been comprised of minehunting and minesweeping tactics using a dedicated force of MCM-capable ships, helicopters, and specially-trained Explosive Ordnance Disposal units. But the legacy MCM inventory is becoming increasingly costly to maintain and is rapidly approaching the end of its useful service life.

Today the Navy is approaching a strategic juncture in MCM where a host of emerging technologies provide new opportunities for widening the traditional approach to mine warfare and could, if successfully executed, bring about a 21st Century renaissance in MCM. Harnessing these new technologies to assist in resolving the very challenging MCM mission set is critical to the future of how the U.S. Navy conducts mine warfare, especially in light of emerging global great power threats.

The list of emerging technologies goes well beyond the additional capability being brought to the Fleet through the modular MCM Mission Package on the Littoral Combat Ship, to include new airborne and unmanned systems and integrated processing capabilities. These systems offer increased speed of operations, faster processing times to identify mines and other underwater objects, and fewer false alarm rates. The modular LCS MP will increase the pace at which Navy formations can clear mined waters. But this is just the beginning for how MCM can transform to conduct future mine warfare operations.

Some of the most salient technological opportunities of importance to naval mine warfare include exploring the integration of artificial intelligence and machine learning; the increasing technical maturity of unmanned underwater vehicles (UUVs) and unmanned surface vessels (USVs), combined with their expanding inventories; assessing new advances in communications, especially underwater; new algorithms being developed for the execution of swarm tactics; the assessment of advances in computer processing speeds; and modular systems engineering techniques for mine warfare.

Technologies and tactics that can help conduct in-stride mine detection are also of keen interest, because dedicated and optimized modular MCM forces will not be available everywhere and at all times. Similar to the tactics U.S. military land forces adopted in Iraq and Afghanistan over the last two decades, the Navy is keen to understand how risk to general purpose forces, operating in a distributed maritime fight, can be reduced through technological and tactical advances that can help these ships avoid the most common mine threats they may encounter. Optimization of ships and submarines for an MCM “mark and move” capability will be critical to ensuring the Navy can maintain freedom of access and maneuver during great power conflict.

To better understand the impact emerging technology poses for MCM and to jumpstart critical thinking, the Navy’s Program Executive Office for Unmanned and Small Combatants (PEO USC) is teaming with the Center for International Maritime Security (CIMSEC) to solicit new ideas. Here are some of the strategic questions that PEO USC is seeking to explore regarding the future of Navy MCM systems:

  • How do we more creatively apply new, innovative technologies to address the operational and tactical challenges posed by mines?
  • Are there better, more innovative operational constructs that can be employed to expand the use of unmanned systems to tackle MCM?
  • How can we employ more innovative operational MCM concepts that seek to take advantage of new technologies and other scientific advances while still maintaining fleet support?
  • Can we re-think the entire approach to confronting the MCM problem?
  • Were we to develop a new generation of MCM tactics and doctrine from first principles, based on our current understanding of technology trends, how might MCM fundamentally change?
  • What new areas of science, technology, or mathematics might we exploit to significantly enhance current and future MCM capabilities?
  • Are we effectively using the right set of metrics and algorithms in MCM?
  • How do we expeditiously translate these new technologies and operational concepts into more flexible and adjustable requirements?

Contributors can answer these questions and more to help chart the course for the future of U.S. Navy MCM capabilities and concepts. Please send all submissions to Content@cimsec.org.

Dr. Sam Taylor received his doctorate degree in Engineering from the University of Memphis in 1994, where his major was electrical engineering. He received his bachelor’s degree and master’s degree in electrical engineering from the same institution in 1990 and 1991, respectively. Dr. Taylor is responsible for the overarching leadership of the Mine Warfare portfolio within PEO USC and works to ensure the seamless delivery of mine warfare capability to the fleet. Prior to joining PEO USC, Dr. Taylor worked at the Naval Surface Warfare Center Panama City Division, Florida, in numerous positions, including the Deputy Department Head for the Littoral and Mine Warfare Systems Department and Chief Technology Officer.

Featured Image: (September 21, 1987) Mines on the Iranian ship Iran Ajr during a personnel inspection of the USS Lasalle in the Persian Gulf. (AP Photo/Mark Duncan, Archive)

Mines of Yemen: Operation SUNNY SALAMANDER

By Patrick Van Hoeserlande


The Yemeni Civil War was an ongoing conflict that began in 2015 between two factions: the then-incumbent Yemeni government and the Houthi militia, along with their supporters and allies. Both claimed to constitute the Yemeni government. Houthi forces controlling the capital Sana’a, and allied with forces loyal to the former president have clashed with forces loyal to the government based in Aden. Al-Qaeda in the Arabian Peninsula (AQAP) and the Islamic State of Iraq and the Levant have also carried out attacks, with AQAP controlling swaths of territory in the hinterlands, and along stretches of the coast.

On 21 March 2015, after taking over the capital Sana’a and the Yemeni government, the Houthi-led Supreme Revolutionary Committee declared a general mobilization to overthrow Hadi and further their control by driving into the southern provinces. A week later they reached the outskirts of Aden, the seat of power for Hadi’s government; Hadi fled the country the same day. Concurrently, a coalition led by Saudi Arabia launched military operations by using airstrikes to restore the former Yemeni government; the United States provided intelligence and logistical support to the campaign.

Notwithstanding warnings from the United Nations (UN) that 13 million Yemeni civilians faced starvation in what it said could become “the worst famine in the world in 100 years,” this war claimed 30,000 dead and hundreds of thousands as a result of a year-long famine.

Finally, in 2021, the fighting fractions came to an agreement on how to govern the nation. With all infrastructure destroyed and institutions neglected, the United States Security Council (UNSC) agreed on the United States Security Council Resolution (UNSCR) 3001 creating the UN Mission for Rebuilding Yemen (UNMRY). The mission’s HQ was in Aden chosen for its symbolic value and its port.

Acknowledging the fragility of the ceasefire agreement between the warrying parties, the UNSC requested NATO to provide the forces for an emergency evacuation of a minimal staff. Although, the UN had plans to reduce, in case of raising tensions, the in-country staff to less than 250, there were indications that in case of an evacuation, more people, not related to the UN mission, would try to get a lift out. Although NATO as the most powerful and cohesive alliance could not refuse such a request, it took the North Atlantic Council (NAC) two months to answer positively.

Soon after the UN started its preparation to deploy the mission, NATO stood up amphibious Task Group Yankee (TG-Y). The vicinity of the port led to the decision that an evacuation via the harbour had the best chances for a flawless evacuation. Due to resource limitations, TG-Y was not a permanent group but assembled during collective training and exercise periods followed by periods wherein the group was spread across the globe. However, nations providing the troops had assured that the group would be ready when needed. To further reduce the burden on the troop-contributing nations, TG-Y was kept on a flexible readiness status in relation to the assessed risk on the ground. An unannounced readiness test by SACEUR showed that the majority of the ships were indeed at the requested readiness, although some nations had stretched the interpretation of readiness.

After the turn of the year 2027, troubles again started in Yemen. Assessing the risk in the first half of that year was troublesome work. As a result, the readiness of TG-Y fluctuated throughout that period. SACEUR urged the participating nations to increase the number of exercises to assure interoperability, and, not spoken out loudly, the readiness of the group. By the end of May, a Houthi militia splinter group threatened a possible evacuation of the UN mission leading to an UNSC decision to initiate the operation. The NAC responded quickly by activating the Execution Order for the Evac Ops SUNNY SALAMANDER. 


In the weeks before the NAC decision, MARCOM’s Ops Centre and in particular its Naval Mine Warfare Coordination Unit (NMWCU) had already started preparing the battlefield. Closely following-up the crisis, they knew it was a matter of weeks for the ‘go ahead’ and they did not want naval mines to spoil the timeline.

Fregatkapitein (BEL) Samantha (Sam) Vleugels was the commander of this small unit and the first Belgian NMW officer trained solely in the use of Maritime Unmanned Systems (MUS). She was one of the first members of the growing group of maritime officers who had never sailed on a manned minehunter ship. Yes, she had done her time aboard, but these ships were not specially designed solely for mine warfare. They were all multipurpose platforms or ships of opportunity. The new mine warfare systems could be deployed from almost everywhere, even on land.

Her Norwegian colleague Flaggmester (NOR) Thorben Jørgensen had served several years on a minehunter. He had loved looking for mines along the Norwegian coastline. Although the latest generation of ships used MUS to ease the task, his adventurous spirit told him that it was more fun to feel the present danger of mines. He was good at his current job, but would immediately go for another tour out there in the icy cold. The rainy weather typical for the British Island made Northwood not an ideal place for a Norwegian sailor to live.

“COMMARCOM asked me to make sure that TG-Yankee can operate safely in the waters around Aden,” she told the chief.

“PSA Charlie did a sweep two months ago. The group is now busy along the Somali coast. We could send them for another run,” he replied. Persistent Surveillance Glider Group Africa Charlie, in short PSGGAC but commonly referred to as “PSA Charlie,” was a loose collection of gliders specialized in seabed mapping. They did not really look for mines, but by using their data and comparing the different surveys over time, artificial intelligence could detect potential targets and classify those targets that were most probably mines, historical or new ones. This kind of information was crucial to assess the mine threat and to prepare a quick countermeasure plan.

She had considered that option too, but found it not sufficient in the light of the events on the ground. “Let’s do that and also retask WTF Africa 05.” Wave glider Task Force Africa 05 (WTFA05) was a group of Mine Hunting MUS (MHMUS) under the control of a wave glider. The latter served as the link between NMWCU and the underwater drones and as a charging station. The central point of WTFA05 was a new type able to operate covertly. It only deployed its antenna when necessary and, if needed, it could dive for a short period. That made it ideal to prepare an amphibious landing zone.

“Good idea. It will take them some days to be on station, but consider it done.” Thorben turned his chair towards the computer screen and formulated the task to both groups. He did not have to command every asset individually, no, he just had to formulate the task of the two groups and the planning software proposed a Course of Action (CoA). If the levels of risk and the operational elements were within the task parameters, he told the AI he agreed with the assessment and things got started. The software decided on the number of assets to retask, ensuring that old and new tasks were executed according to the stated parameters.

Just for his awareness, he requested the computer to run a simulation of the proposed CoA. He also had a look at the risk maps based on the last survey of PSA Charlie and interacted with the AI to prioritize some promising corridors for demining. Happy with the result, he called it a day.

Vleugels and Jørgensen felt successful when they heard that Ops SUNNY SALAMANDER was initiated. It was the first time that the new concept was put to a test and they already scored. In the old days, only a mine hunter TF could be sent to the area. As these ships were not made for speed, the first part of the operation would already have delayed the whole operations. Speed was of the essence and this time the naval mine threat would not delay the action.

“The assumption of the plan was that TG-Y would sail to Yemen via the Suez Canal, but because they are on exercise in the Atlantic the fastest transfer is via the Arabian Sea. PSA Charlie did a survey there and we can use ‘Ocean of Data’ to identify potential mines in the route, but we lack a minehunting capability,” concluded Sam. “Ocean of Data” was a database of oceanographic data maintained by a company using civilian MUS. Although not as detailed as the military’s own, for deeper waters this data was good enough. Because NATO provided unclassified data collected with the national MUS, the unit had easy access to this database through a partnership agreement.

“The task group does not have a minehunter with them. There are no ships in the vicinity that we can use as a vessel of opportunity,” answered the chief.

“Let’s broaden our possibilities. Does AIRCOM have access to MHADs?” she replied. MHAD or Mine Hunter Air Delivered was an underwater drone designed to be dropped by almost any aircraft or helicopter. This made it an ideal asset for speedy delivery of a minehunting capability.

He started a search in the database of stand-by capabilities and answered:” Yes, AIRCOM has MHADs available. France has offered them for the current stand-by period.”

“OK, send AIRCOM a request for support and make sure that SHAPE is in CC,” she ordered. While he launched the request, something was bothering her. Not all mines were huntable. Having only minehunter drones in the area would not be enough.

“Chief, are there minesweepers in the area?”

“Negative. No ships, no drones,” while he kept on typing, “but … the USS Michigan is not that far away.” 

“Does she carry LBMS?” LBMS or submarine-launched Large Body Mine Sweepers were torpedo-like workhorses designed to tow a minesweeping array. Before the chief could give her answer, she was heading to the submarine warfare unit. Sam knew that he could not answer her question because that kind of details on subs were not readily accessible, and even if they were, she had to ask her colleagues to get out the task.

USS Michigan  

The USS Michigan, commissioned in 1982 and the third ship to bear the state’s name, was a United States Navy Ohio-class nuclear powered ballistic missile submarine converted to a guided missile submarine (SSGN-727). Later she had undergone a modification to accommodate special weapons and to serve as a mothership for unmanned underwater vehicles.

After they had changed their course toward the Arabian Sea, they arrived at their firing position. Although they would not fire the sub’s normal weapons, the crew used the standard tactical vocabulary.

“Tubes one and two ready, sir.”

Captain (USA) Jean-Jacques Smith smiled when he heard the reply. His parents were both vivid divers and they named their son after the famous French diving pioneer Cousteau. Their love for the underwater world had turned his gaze towards the silent world of submariners. The mystery of the dark held him in its grasp.

A second “Sir?” brought him back to the task at hand.

“Launch number one.”

A metallic sound followed by a whoosh marked the departure of the first LBMS.

“Torpedo one away.”

“Confirmed. LBMS one is active.”

“Launch number two.”

 “Torpedo two away.”

“LBMS two also active.”

“Confirm the launch to HQ and bring us back to our holding station.”

“Aye, sir.”

His order was further translated to the different stations of the sub. The highlight of the day was over, now they had to make sure that the sub slipped quietly into obscurity without any detection.


The night shift briefed on the successful launch of the LBMS and the preparation of a German A400M sub-strategic airlifter to drop the MHADs. They confirmed that the robotic sweepers were already sweeping mines cooperatively on the far segment of the approach to Aden.

When Sam entered the area of her unit, Thorben had verified the activity of the two minesweepers. The first elements of WTFA05 were already busy hunting mines in the last leg of the sea route and PSA Charlie was active in other potential landing zones. Things were going well.

“What’s the status of the A400M?”

“According to the Info from EATC the aircraft will leave at 1000 for Cazaux Air Base to pick up the two DHAMs.” The European Air Transport Command or EATC was a single multinational command with its headquarters located at Eindhoven Air Base, the Netherlands. The fleet of over 300 assets were located at the national air bases through the twelve member nations.

She looked at her watch and decided they still had some time. “The Task Group wants a minehunter ship in front of them and the admiral agreed to it.”

“But that doesn’t make sense. The drones are doing a good job. The route will be clear. They don’t need a ship.”

“I know, but the old guys don’t trust what they don’t see. They want a ship to feel safe. The Mine Warfare advisor Captain Wiegmann could not convince his COMTF, so we have to stick to the task.”

“The German captain is a decent guy and a great specialist. If he was not able to turn the decision, nobody can,” answered the chief.

“Do you know him?”

“Yes, I worked with him during exercise ARTIC MINE. Great commander.”

“Then you will be glad to see him because he is online now.”

That moment Kapitän zur See (DEU) Rolf Wiegmann’s face appeared on the right screen. He was an old-school mine warfare specialist but experienced in the use of new technologies.

“Hi team. I guess you have heard about my admiral’s request?”

“Yes commander, we are aware of it.”

“Any proposal on how to get a ship for us?”

“There are no ships around. Not even an ‘Old Lady,’ so we have to go for another solution,” said Thorben. Sam did not like the expression “Old Lady” for a worn-out, stripped ship equipped for (semi)autonomous operations in a minefield. These ships, small or big but always old, could be used as minesweepers but also as a quick and dirty test for the presence of mines. Through the years she had accepted that sailors talked about a ship as a ‘she’ and that there was nothing odd about that. But, sending an old lady unprotected into a minefield was still hard to accept.

“Looking at the characteristics of the local seabed, an ABNL – the Belgian-Dutch maritime cooperation – ship would be perfect because she could be used to assist the landing if necessary. The Dutch and the Belgian are accustomed to operate in sandy conditions,” Sam declared with some proudness in her voice. The chief picked up that tone and knew she was right. His navy was specialized in rocky coasts, but these were not found around Aden.

“They are too far away to be on time. Their operational ships are participating in the live clearing activity in the Baltic Sea. Even if they turn around now and sail at high speed they will arrive after D-day.”

“Right,” she sounded a bit disappointing.

“We have a Portuguese Fast Multi-purpose Support Ship ready to sail out and join the naval exercise in the Mediterranean Sea. If we ask it to sail through the Suez Canal, it could join the task group in time,” proposed Thorben.

“Let’s do that,” replied Rolf. “What about the mine clearing module? I know the Portuguese don’t have those yet.”

“We could ask Den Helder to provide us with one of their modules. If we fly the container to Port Said International Airport, the Portuguese ship could pick it and the crew up,” proposed Sam regaining her enthusiasm.

“Great idea,” confirmed the chief.

“Okay, team, keep me posted and if you need my support, don’t hesitate to call me. Rolf out.”

“Nice to have this figured out.”

“I’ll talk to my national chain of command; can you take care of the Airbus for me?” Sam asked.

“Already busy with it.”


After the pick-ups in Melsboek, Belgium, and Cazaux, France, they had been flying to Said. A quick stop to drop of the mine clearance module and its crew of six, they refuelled the plane and took off again. According to their flight plan, their current leg would soon end above the Red Sea.

A buzzing sound announced the opening of the cargo door. The noise of the four turboprop engines swelled and filled the cargo bay. The crew chief looked down and saw the inviting surface of the Red Sea. It was dark and there were only distant lights. Good, nobody is watching was the thought that went through his mind.

“Cargo door open and locked. Ready to drop.”

“Roger that,” responded the pilot.

The red light went on indicating that the loadmaster had to start the final check. The parachutes were hooked on. The cargo clams blocked in the right direction. Nothing visible that could hamper the release.

A nightly parachute extraction drop was always spectacular and dangerous. Once the main release handle was pulled over, there was no stopping to it. Everything, intentionally or not, attached went overboard. The two air force specialists had no intention to drop something else except the two DHAMs. They did not really know the purpose of this drop. They did not care. Their task was to execute a clean drop.

The orange light went on. Instinctively they both stepped back into safety.

“Crew chief clear.”

“All clear in the back.”

Green light.

Immediately, the loadmaster pushed the handle and the parachute left its storage place. Taking air at high speed, it instantly deployed fully and with a hard jerk, it yanked the container out. They could hear the noise in their active noise reduction headsets. They both witnessed the white splashes of the two DHAMs, but lost all sight of the black chute.

“Closing door.”

“Going home,” replied the pilot.


“All systems functioning as planned. Sea approach cleared above requested confidence level,” stated the report.

“The Portuguese ship will join us in the afternoon. Everything will be ready for the evacuation, admiral,” concluded Rolf in his briefing.

“Job well done, Rolf. Thank MARCOM for me,” responded COM TASK GROUP YANKEE.


“Our German captain sends us thanks from his boss. A job well done,” said the chief. It was the first time that they had used the new concept of MCM operations to prepare an amphibious operation. All those years against critics finally paid off. The underwater drones enhanced by AI did what they were supposed to do.

Suddenly the screen flashed red. A red rectangle warned them about an explosion. This warning came from the wave glider of WTFA05. Its hydrophones had picked up the noise of the explosion. The next line informed the unit that MHMUS 04 was damaged and sinking to the bottom. Chief Jørgensen started the forensics diagnostics program to have a better idea of what just happened.

“It looks like a commercial ship was leaving the port while MHMUS 04 was busy neutralizing a mine. The ship must have come too close to the mine, so 04 decided to let it explode before it could finish the job,” explained the chief.

“Why did it do that?” wondered Sam, although she knew the answer.

“We think that these drones do that to protect the ship and prevent collateral damage, but we’re not sure. Their program has learned it that way and the manufacturer left it as it was,” Thorben explained. Sam knew that was half the truth. The manufacturer had no idea how the AI-based software had come to that conclusion and was unable to de-program it. AI was not a rule-based software but the result of endless iterations of data interpretation cycles. Changing the outcome was not as easy as changing a line in the software.

“Nothing we can do about it. Note that we have to pick up the damaged drone in the near future. A task for the Portuguese?”

“OK, I will launch a request for that,” answered the chief.

“I wonder how the other side will react to that incident.” 


“Good morning team,” said Rolf.

“Good evening. You have read our report on the explosion?” asked Sam.

“Yes, thanks for that. Any changes?”

“No, no reaction from the other side as far as we can detect.”

“Okay. Our MQ-10 is on station. I’m forwarding its feed to your station now.” The General Atomics MQ-10 Havoc (sometimes called maritime Reaper) was an unmanned aerial vehicle (UAV) capable of autonomous flight operations developed primarily for the United States Navy. The MQ-10 was an improved version of the MQ-9 hunter-killer UAVs and designed for long-endurance, high-altitude armed surveillance.

“We have it. Thanks,” replied Sam. “Can you fly over SIERRA beach? We want to see if there are mines in the breakwater zone.”

The drone operator changed the course a bit and swept the camera towards the beach where the special operations team would go ashore.

“There, and there, and maybe here,” said Thorben while his pointer went over the spots on the image from the camera. “Possible UWIEDs.” The homemade naval mines or Underwater Improvised Explosive Devices were placed to prevent an assault from the sea. Because they were positioned in the breakwater zone, they were hard to detect with a MUS. The UAV’s multispectral camera was a great help to detect possible mines in shallow water.

“There is a truck on the beach,” announced Rolf.

Immediately the operator zoomed in on the truck. All saw the cargo in the back of the truck. They all thought the same: more UWIEDs.

“Should we destroy the truck?” asked Sam.

“Yes, they could add more mines. We can hit it with our gun,” proposed Rolf.

“Wait a moment!” It was the chief. “Can you hit this spot first,” he said while marking a spot in the shallow water of the beach, “and then walk towards the truck?” On the second screen they could see the map with estimated mine threats. There was a dark green area running to the indicated spot. They understood that the requested firing pattern would clear possible UWIED in the breakwater. It would open a safe passage for the SOF team without giving the intent of clearing an infiltration path away.

They heard a long drumming sound and a moment later, the camera filmed the effect of the rapid fire. Water spewed up followed by a destructive trail towards the accelerating truck that ended up in a ball of flames. It was a beautiful but deadly spectacle.

With an alarming sound, a red text popped up: POSSIBLE ONGOING MINE LAYING OPERATION DETECTED. “Helvete! Can you turn the camera to the entrance of the port?” asked the chief in disgust.

The screen turned blurry to stop with an image of the inlet. Without being asked, the drone operator zoomed in on the deck of the ship. They were witnesses of the drop of another sea mine. There were still some mines left on the small ship. If they would allow this crew to continue their activity, their preparatory clearance work would be in vain and the whole evacuation operation would have to be postponed. This in turn would increase the risk for the UN staff.

“Deal with it!” Rolf requested without consulting the others. The operator threw a quick glance at her mission leader who gave an approving nod. Two seconds later Fox 1, an advanced small calibre air-to-ground missile, left its rail. The missile rushed towards its target turning it into a burning wreck. The secondary explosions were violent witnesses that the ship’s cargo of sea mines were destroyed as well.

They did not have time to enjoy this little victory as Thorben announced that the computer estimated that the Houthis probably had dropped four sea mines. Enough to delay the operation with some days depending on the type of mines. “Our gunfire must have shielded the noise of their sneaky activity,” he concluded.

Disappointment quickly followed victory. The two operation centres turned quite.

With “Can you show me the results of the surveillance by PSA Charlie?” Sam broke the loud silence.

“Sure thing.”

“Right, have a look at the beach to the East of Little Aden.” All eyes followed the move to the East. Sam zoomed in. They all recognized the way out. There was a stretch of at least 200m of dark green on the chart. An amphibious landing zone. “Go where there are no mines” was one of the catchphrases in the concept. A pass by the MQ-10 would confirm the absence of UWIEDs in this breakwater zone. The operation on the ground would be a bit more complicated, but it was doable within the planned timeframe.

“Quick thinking team,” were the thankful words spoken by Rolf.

“Thanks. It’s part of the job description.”


“Does the task group still need the Portuguese ship?”

“Why do you ask?”

“Well, this little action we had, made me think. We can use it to reinforce their idea that we will use the port for exfiltration and recuperate the damaged MHMUS 04.”

“Elaborate,” asked the captain.


After the captain had explained their deception plan to his commander, the multipurpose ship with the ABNL modules sailed toward the port of Aden. At a safe distance, the crew put up a good show of a demining operation. They even ignited an old sea mine to increase the theatrical effect.

Observers of their activity at sea quickly concluded that the Houthis had at least five days before the port would be accessible. Time enough for their own plans.

However, the real activities under water had no relations with this show. Mine hunter drones were widening the green zone of SIERRA beach while another drone salvaged the damaged number 4.

As planned, in the middle of the night the SOF team came ashore and organized the evacuation. The surprise was complete and all staff evacuated safely and without real incidents.


The Secretary General read the UNSC letter felicitating NATO for the flawless evacuation of its staff out of Yemen. Listening to the diplomatic sentences, Captain Wiegmann reflected on the excellent work of the team and the value of the new concept. In the old days, this evacuation would have been much more difficult to pull off.

Major Van Hoeserlande (BEL Air Force) is an aeronautical engineer with thirty-five years active duty on the counter, including command tours and deployments in joint environments. His love for writing and storytelling started in high school and has never panned out. As a diver-editor most of his articles are about underwater adventures, but his interests include innovation, management, technology and travel. As from August 2018, he is concept developer in NATO’s Strategic Headquarter in Norfolk, VA and uses stories to illustrate conceptual ideas. The views presented are those of the author, and do not reflect the views of NATO or Belgium.

Featured Image: Underwater minefield by Juan Jose Torres