Professional Notes

The Planner's Objective

A properly planned minefield has a specific military objective. Besides damaging and possibly sinking ships, it may be planted to funnel a task force into a given area in which defending forces have concentrated resources to decimate the attacker's assets. The planner's objective may be to affect the psychology of the attacker, hoping to influence him into changing his mission plans and delay his advance. For our discussion, the minefield's objective is to sink ships or to damage them sufficiently that they can no longer complete their mission (mission-abort damage).

The sensitivity level of a mine must be set so that its actuation contour matches as closely as possible the maximum distance at which its explosive charge can inflict mission-abort damage to the passing ship (mission-abort damage contour). If the mine is set too sensitive, it may explode at such a large distance that the planner's desired minimum level of damage is not achieved. In this case, the mine is wasted and eliminated as a threat.

If the mine's actuation threshold is made too insensitive, targets may pass without it firing at all. Then the planner risks a catastrophic failure of the entire minefield, posing no threat or damage to any transiting vessel.

Degaussing and Shallow Water

A planner is consistently challenged to correctly select firing sensitivities for the minefield that will result in actuation contours matching the weapon's minimal acceptable damage level. Difficulties increase if the minefield's targets are military vessels that could be equipped with signature reduction systems, such as degaussing. If the target ships are known to be degaussed and have reduced magnetic field levels, then the planner must increase the sensitivity settings of the mines to avoid a catastrophic failure of the minefield.

The difficulties can be demonstrated with an example. In this scenario, the mines have five sensitivity settings, no. 1 through 5, corresponding to five magnetic field actuation levels—3,000 nanotesla (nT), 2,000 nT, 1,000 nT, 500 nT, and 250 nT, respectively. If a passing ship's magnetic field exceeds the actuation threshold of the sensitivity setting selected, the mine will detonate. 2

The planner must choose an actuation threshold that the target is expected to produce at the mine's maximum mission-abort damage distance, requiring sensitivity adjustments for the water depth in which it is to be planted. If the target ships are expected to be undegaussed, then the planner may select setting no. 1 (corresponding to a 3,000 nT actuation field) for mines deployed in shallow water. At deeper depths, the target's undegaussed signature may be only 500 nT at the mine's maximum mission-abort damage range. In this case, an optimum sensitivity for the mine might be no. 4.

Although a mine's actuation level must be adjusted according to the water depth where it is to be deployed, matching its actuation sensitivity to its mission-abort damage contour is generally not difficult when facing undegaussed vessels with large signatures. If a transiting vessel is expected to be equipped with signature reduction technology, which may have lowered its magnetic field down to, say, 2,000 nT in shallow waters, then the mine's setting will have to be changed to no. 2 to avoid the possibility of a failure of the minefield.

However, degaussing systems not only lower a ship's magnetic field, they also cause its signature amplitude to fall off with depth at a faster rate than the undegaussed case. As a result, the magnetic field of a degaussed vessel may now be lower than the actuation threshold of the mine's maximum sensitivity setting (no. 5), even at moderately shallow depths. Degaussing systems increase a ship's safe operating area, swiftly regaining control of those waters that have been seeded with magnetic bottom mines.

Reducing Signatures

Equipping naval vessels with an advanced degaussing system could further reduce their signatures and susceptibility to actuating mines. If these advanced degaussed ships have shallow water signature levels of 250 nT at the mine's mission-abort damage range, then the minefield planner will have to increase the mines' sensitivity to no. 5.

At only slightly deeper water depths the field levels of the transiting vessels may be much less than 250 nT, enabling their safe passage over the magnetic bottom mine at its most sensitive setting. The increase in safe operating area can be achieved without increasing the number of active mine countermeasure platforms or spending critical mission time to clear the minefield.

Of course, moored mines still have to be countered, though this can be accomplished much more rapidly and with less mine countermeaures (MCM) effort than a comparable bottom minefield. Eventually all magnetic bottom mines must be actively hunted or swept, so that commercial ships and those military vessels not equipped with degaussing systems can safely sail through the area. But this can take place at a latter time, when the demands of the mission and availability of MCM resources allow.

Very Shallow Water

Consider an example of an amphibious assault task force transiting a hypothetical minefield along a "Q" route (transit lane) extending from deep water to very shallow. In this scenario, the task force comprises vessels equipped with advanced degaussing systems, making them invisible to magnetic bottom mines in the deep portion of the Q route.

As a result, all MCM resources that would otherwise be assigned to counter magnetic bottom mines in deeper waters can instead concentrate on the very shallow waters closer to shore.

When magnetic bottom mines are planted in very shallow waters, the minefield planner should have no difficulty in adjusting mine sensitivities to match their maximum damage contours, even for advanced degaussed ships. However, mines that are set on a high sensitivity to attack vessels with low magnetic signatures are more easily swept. (Mines on setting no. 5 are more easily swept than those at 1.)

A direct relationship can now be established between ship signature levels and effective sweep widths: Lower ship signatures force more sensitive mine actuation settings, resulting in an increase in sweeping efficiency against more sensitive mines.

If the minefield planner tries to avoid this increase in sweep efficiency by not raising sensitivities even though he knows that the transiting vessels' signatures have been lowered, then he risks a failure of the entire minefield.

But a mine designer may incorporate features into the weapon to prevent it from being easily swept, regardless of ship signature levels. Sweep-resistant or "smart" mines exploit differences in the influence signatures of ships, background noises, and sweep systems, to determine if a valid target is present. Smart mines are designed with multiple decision points in their firing logic to classify the source of a detected signal as noise, a minesweeping system, or a valid target.

But these extra decision points inserted into a smart mine's firing logic are actually vulnerabilities that can be exploited to prevent it from detonating. Onboard or off-board devices that generate influence fields to confuse a mine's logic and prevent it from reaching a firing decision while a ship sails past it are called mine-jamming systems. Work is under way to develop both environmental and organic mine-jamming systems. 

Countering the Threat

Lower magnetic field signatures can eliminate the need for bottom mine clearing operations in deeper waters, and can increase sweeping efficiency in very shallow waters. Mine hunting and sweeping, signature reduction, and jamming are all tools to reduce the risk to a ship when transiting a minefield.

But they are not to be used in isolation. Instead, MCM technologies and operational tactics must be employed in an intelligent and harmonious fashion with signature control, to obtain maximum protection of ships within the constraints of their mission. To eliminate naval mines as a threat, we must grasp and leverage the direct relationship between ship signature levels and the effort needed to clear a minefield with active MCM systems.

1. "U.S. Navy Marine Mammal Mine Hunting System," U.S. Navy Marine Mammal Program, Space and Naval Warfare Systems Command, 18 July 2005, .

2. John Holmes, Exploitation of a Ship's Magnetic Field Signatures (Denver: Morgan & Claypool, 2006).

Dr. Holmes is the senior scientist in the Underwater Electromagnetic Signatures and Technology Division at the Naval Surface Warfare Center, Carderock, Maryland. He has written two books and several articles on underwater electromagnetic signatures and their reduction. He is chairman of Syndicate 2 of the NATO Naval Mine Warfare Working Group that is responsible for establishing technical standards for naval mine warfare systems and equipment. 

Language of the Mind: Cross-Cultural Preparation for Marine Advisers

By Lieutenant Colonel Thomas D. Affourtit, U.S. Marine Corps (Retired)

Insight into yourself is the first and perhaps most important prerequisite as you prepare for assignment as an adviser. What do you bring to the counter culture? How will your own motivational characteristics, strivings, and needs impact not only the new environment, but your human counterpart as well?

To develop cross-cultural expertise, advisers must understand themselves, in particular in relation to their counterparts. A better understanding of the interpersonal relationship will reduce the time needed to build rapport, establish trust and confidence, and gain the deeper insight necessary for promoting adaptation.

The U.S. Marine motivational profile displayed in Figure 1 was developed from a sample of Marine advisers training for duty in the Middle East. 1 The Arab Muslim comparison group comes from a sample of Arab college men located in Jordan. 2 The line through the middle of the figure (50th percentile) represents the U.S. Male Standard. 3

More Leadership-Oriented: Marines

Compared with the Marine adviser, the Arabs sampled were not as achievement oriented (ACH). Marines may see Arabs' need to excel or accomplish as somewhat lacking. This differential is most likely more severe in a non-college Arab population, where emphasis on fate rather than self-determination is more pronounced. Marines, therefore, have to be reasonable with regard to setting goals, and tolerant of their counterparts' willingness to accept failure as the will of Allah. Positive reinforcement of any accomplishment will reap the best rewards for Arab advancement.

Arabs, as well as Iraqis, were not as motivated as their Marine advisers to assume a leadership role, take charge, or make decisions. They may seem hesitant and uninspired with regard to assuming command. However, in general, this sample of Arabs was much more willing to take orders (deference, DEF), and to seek guidance from the Marines. 4

Again, this is a general pattern, and variation within the population should allow the Marines to identify those who are more disposed toward leading others.

Another contrast between the Marines and their Arab counterparts was the latter's strong need for order (ORD), i.e., to maintain the status quo, to retain a proper sequence of events. Marines were much more flexible in this regard. Trained to function within a more confused environment, Marines adapt more readily to changing events. By comparison, the fog of war may bewilder the Arab soldier.

More Socially Oriented: Arabs

On the social side (affiliation, AFF), the Arabs were much more inclined to be friendly and to participate more often in social activities. The Marine sample was not necessarily indifferent socially, yet they were not as gregarious as the average American male standard. As a result, Marines may appear somewhat aloof and unfriendly by Arab standards.

The characteristics of nurturance (NUT) and succorance (SUC) have historically been associated with females in U.S. society. Understanding and kindness toward others, especially those less fortunate, is a fundamental Islamic principle, a core value of the five pillars of Islam. Arab self-respect is tied to the display of generosity and sympathy. Conversely, seeking sympathetic indulgence from others is the reverse side of this characteristic.

Marines may be favorably impressed with Arab warmth and expression of tenderness, but at the same time, they may consider the outward display of these characteristics to be distasteful. For example, Marines report an aversion to "man kissing" as a sign of affection and acceptance by Arab males. 5

Similarities and Differences: Cultural Conditioning

Arab self-abasement (ABA) stems primarily from a strong sense of Islamic fatalism, evoking feelings of hopelessness and perhaps self-blame, especially when things go wrong. Marines, on the other hand, are unaccustomed to such displays of emotion, especially within a military population. The Marine adviser may view his counterpart with disdain at this display of what may be considered a weakness, akin to defeatism. But if the Marine adviser can understand that this behavior is ingrained in the national culture, and if he is willing to accept the difference, he can temper his reaction or perhaps indulge the trait for the sake of mission accomplishment.

On a more positive side, Arabs are disposed to learn from their American trainers. They are open to gaining new skills, and willing to accept change (CHG), as long as it does not conflict with or corrupt Islamic principles. Arabs realize that acceptance of some Western principles is essential to regain preeminence.

Arab curiosity and inclination toward learning is reinforced by their high endurance (END) score. Perseverance and persistence of the Arab mind are often mentioned in the literature. This characteristic should be of value to Marine advisers as they prepare the way for Iraqi self-sustainment.

Both Arabs and Marines in this sample manifested an interest in understanding differences between themselves and others (intraception, INT). This is a very favorable characteristic in interactions between cultures. It signals a more open personality, and a willingness to interpret cultural nuances in a less-judgmental manner.

Aggressiveness (AGG), as defined by the scale of measure, was high for both Arabs and Marines. However, the operational difference between the two groups may, again, be a matter of expression. The Arab male culture is well known for an argumentative nature, verbal intemperance, and inclination toward threats. Marines, on the other hand, are perhaps more inclined toward physical competitiveness.

Finally, there is a highly significant difference between the Marine adviser and the Arab male with regard to the manifestation or expression of heterosexual interest (HET). It is well documented that Arab societies repress heterosexual expression and involvement early in development, with a lasting effect into adulthood. Much of anti-Western sentiment is associated with a concern that Arab mores will be corrupted by American values. And Western displays of opposite moral codes in Arab communities have been used by anti-coalition forces to recruit insurgents. Marines, therefore, must be aware of the extreme difference and moderate their behavior accordingly.

How to Learn about Yourself

The profile comparison described here reveals significant differences and similarities that identify critical stress points for an adviser and signal the need for adaptive response. The results substantiate, for the most part, what is already known about the Arab culture from a Western perspective. The Marine adviser profile sharpens the picture and details the contrast.

However, the primary benefit derived from this method occurs when the individual Marine gains insight into his own strengths and weaknesses relative to the Arab culture. This understanding opens the door for adjustment toward more effective behavior.

At this point, much can be gained from individual insight and counterpart comparison. Armed with his profile, the adviser is more capable of monitoring his behavior and correcting his course. Moreover, enlightened leadership is more capable of identifying dysfunctional behavior that may require adjustment or reassignment.

Displaying his profile to me, one Marine master sergeant asked whether he would make it as an adviser. The profile revealed extreme variation in dominance (DOM) and aggression when compared with the Arab sample. I told him that his expression of concern was a catalyst to motivate him to temper his approach to the situation.

The characteristics that make him an effective leader in the Marine Corps will not necessarily render him effective in another culture. But adaptation will make him a more expansive leader in the future. By understanding his strengths and weaknesses and allowing himself to adapt or request reassignment, the adviser will be better equipped to accommodate the stressful situation and avoid adverse career impact.

Personal insight is just one weapon in the Marine adviser's inventory. It gives him an edge, along with other skills he brings to the event. Collectively, his abilities can mean the difference between success and failure, or perhaps life and death. The difference between the Gold Medal and eighth place in the 2006 Olympic downhill ski race was only 1.29 seconds. Hopefully, the insight edge will help our Marines become Gold Medal advisers.

1. The Marine sample comprised 1,358 advisers (LCpl to Col), 2004-08. Administration was voluntary and anonymous, in keeping with the ethical standards of the American Psychological Association, and legal constraints governing the use of such techniques.

2. While the Arab sample does not exactly represent a military group, the profile does conform to empirical descriptions of the Arab culture found in literature and is reinforced by feedback from Marine advisers recently returned from Iraq.

3. The assessment technique, based on the theoretical formulation of H. A. Murray, yields a profile of relatively independent normal personality variables. Validity has been established by more than 60 years of research.

4. This finding is in sharp contrast to a Vietnamese military sample. They were also disinclined to assume leadership, but were relatively unwilling to follow direct orders, leading American advisers to judge them as stubborn and resistant to authority.

5. While the Marine standard shows an opposite trend overall, some were inclined toward the same characteristics common in the Arab population. It is not unusual for U.S. males to embrace these traits. However, it is the manner in which these inclinations are expressed in other cultures that brings into question one's masculinity.

Lieutent Colonel (and Dr.) Affourtit is the founder and president of Interaction Research Institute, Inc. He has been conducting research and training overseas advisers since the Vietnam conflict in 1971. Since 2004, he has prepared Marines for advisory duty in Iraq, Afghanistan, Africa, and elsewhere.


UAVs Can Be Sub-Launched and Recovered, and More

By Robert A. Ruszkowski, Captain Karl M. Hasslinger, U.S. Navy (Retired), and Captain Robert L. Lowell, U.S. Navy (Retired)

Reusable multipurpose unmanned aerial vehicles (MPUAVs) operated from submarines could provide long-range, stealthy, all-weather reconnaissance and specialized mission support in many scenarios. They could also be operated interchangeably with surface ships.

The Navy has completed conversion of four Ohio -class ballistic missile submarines (SSBNs) to guided-missile submarines (SSGNs). Each SSGN possesses significant payload volume and flexible ocean interface, with its 24 Trident missile launch tubes. This capacity invites continued innovation to find ever more useful and capable payloads. The MPUAV may be just such an SSGN payload. In particular, the unique combination of inherent submarine stealth and a stealthy MPUAV capable of carrying interchangeable payloads could enhance the ubiquity and persistence of U.S. forward deployed forces.

Consider the following future scenario. An SSGN covertly patrolling a contested littoral in advance of other maritime forces is tasked to conduct an intelligence, surveillance, reconnaissance, and targeting (ISR&T) mission of suspected weapons of mass destruction sites deep in hostile territory. Two MPUAVs with sophisticated sensor packages are released from the submerged SSGN. Later, the MPUAVs initiate launch and enter hostile air space with speed and stealth, to collect intelligence directly and/or deploy additional sensors, such as unattended ground sensors. Completing their mission, the MPUAVs fly to a planned at-sea rendezvous point for recovery by the submerged SSGN.

As activities increase at the weapons sites, the SSGN is tasked to acquire below-the-weather, high-resolution, target imagery via additional MPUAV sorties. The geo-registered imagery is fused with data from national systems to document hostile intent and determine aim points for the precision strikes using cruise missiles.

Shortly after the initial strike, MPUAVs collect battle-damage-assessment imagery that is combined with unattended ground sensors or other inputs to direct follow-up strikes. Hostilities escalate, and the MPUAVs are selectively used to provide targeting, battle damage assessment, and focused jamming and information warfare support for follow-on forces.

Reusing MPUAVs

This scenario raises an important question: Why not use expendable UAVs? Certainly, expendable submarine-launched UAVs could have significant utility. The MPUAV is envisioned to complement these expendable systems by providing higher levels of capability that could be reused over longer periods.

Currently envisioned expendable sub-launched UAV systems would have limited payload capacity, range, and speed. Their effectiveness would likely be restricted in more severe weather conditions, due to their relatively small size and slow speed.

In most scenarios involving countries with significant military capabilities, it is assumed that high-value targets would be protected by sophisticated surface-to-air missile systems. Such defenses may preclude even stealthy aircraft—manned or unmanned—from closely approaching targets or from direct overflight. Therefore, the sensor systems carried by a UAV would need to be capable of high-resolution collection at significant ranges for target identification.

This reality drives sensor aperture size and power for electro-optical, infrared, or synthetic aperture radar systems. Such state-of-the-art sensor systems can weigh hundreds of pounds, occupy multiple cubic feet, and require significant electrical power. Thus, these high-capability payloads can dictate the size of the UAVs needed to carry them.

Further, these sensor systems can be relatively expensive and/or contain sensitive technologies. Integrating them on board expendable UAVs may be cost-prohibitive. And a submarine carrying only expendable UAVs faces usage limitations inconsistent with its ability to remain on station for extended periods without escorts or logistic support.

Launch and Recovery from SSGNs

To initiate air operations, a submerged SSGN extends and releases an MPUAV from a Trident missile launch tube. The MPUAV rises to the surface, where launch force is provided by two disposable solid rocket boosters similar to the Tomahawk cruise missile booster. The MPUAV turbofan engine is rapidly started during the launch ascent, and the boosters are jettisoned after burnout. Upon mission completion, the MPUAV returns to a designated retrieval point at sea, initiates engine shutdown, and splashes down.

After splashdown, the buoyant MPUAV floats until rendezvous with the recovery SSGN. The submerged SSGN deploys a remotely operated vehicle (ROV) to secure an in-haul cable to a tether deployed from the MPUAV. The SSGN then hauls the MPUAV toward a launch tube saddle mechanism, where the aircraft docks. With wings folded, it is retracted into the launch tube, the hatch is closed, and the tube is depressurized and drained.

Once on board the SSGN, a hands-off servicing concept is envisioned to include freshwater wash-down, attachment of rocket boosters, refueling, and payload reconfiguration, if required. The MPUAV can then be relaunched at a later time.

An Immersible MPUAV Is Feasible

Given typical operating depths for launch and recovery, the MPUAV needs to withstand moderate hydrostatic pressures while remaining watertight, and it needs to be resistant to saltwater corrosion. In 2003, a study funded by the Defense Advanced Research Projects Agency was conducted to ascertain the feasibility of an immersible submarine/sea-launched and recovered MPUAV. Specific immersibility features were evaluated; SSGN-MPUAV interfaces were defined; and launch, recovery, and servicing concepts were refined. Here are some of the key findings from that study.

  • The MPUAV will rely on an onboard pressurization system to offset the expected hydrostatic pressures during submerged launch and recovery operations. Such a system eliminates the need to design the airframe to withstand the total expected hydrostatic loads and accommodate the attendant weight penalties.
  • The turbofan engine and propulsion system will remain dry when submerged via a combination of actuated watertight inlet and nozzle doors and internal pressurization via the system described above. These close-off doors feature inflatable seals around their perimeters. The seals are similar to those used on fighter aircraft canopies and will be inflated by the onboard pressurization system.
  • Access panels will not be open during routine servicing on board the SSGN. Such access panel perimeters and manufacturing seams will be made watertight with a combination of silicon-based compounds derived from aircraft fuel tank sealants. Additionally, these seams may include an external treatment of paintless film adhesive appliqus.

Successful Demonstrations 

In fall 2006, the recovery concept of the MPUAV was successfully demonstrated in the Hood Canal near Submarine Base Kitsap, Washington. This culminated in an end-to-end test event from splashdown to recovery cable coupling by an ROV, through inhaul and submerged docking. A full-scale mockup of an MPUAV design, a Naval Undersea Warfare Center ROV, and a large test rig simulating the launch and recovery mechanism were used. This first-of-its-kind testing was part of an 18-month Phase 1 project that was a follow-on to preliminary studies. (The MPUAV is now in a concept-development phase. Should it enter production, Lockheed Martin envisions making the aircraft and working with General Dynamics-Electric Boat to handle the launch and recovery mechanism, servicing systems, and other aspects of submarine integration.)

Phase 1 also completed other key risk reduction testing and design work. The rapid engine start demonstrations pioneered the feasibility of repeated, rapid, clean starting of a medium-size turbofan engine. A full-scale forward fuselage test article was used to measure data for critical splashdown loads and verify the watertight integrity of the inlet close-off door. New analytical techniques were developed to simulate the splashdown dynamics and forces. The ROV-assisted recovery cable hookup demonstrations proved the feasibility of intercepting a tether deployed from the buoyant MPUAV and coupling the recovery cable to it for submerged recovery inhaul operations.

This was a prerequisite to the full-scale tests, but it may also be extensible to the recovery of other buoyant payloads or resupply pods for the SSGN itself. The launch and recovery mechanism design provided the basis for a system that could be accommodated in a SSGN Trident missile tube for extending and retracting a wide variety of future payloads, including an MPUAV.

Future Payoffs

The MPUAV concept could provide sustainable, renewable air operations that would be organic to the SSGN or other submarines with large payload tubes. Surface ships such as littoral combat ships may also be able to operate MPUAV, because this new class of aircraft can be launched and recovered from a buoyant state in the water.

However, the combination of a stealthy submarine and a stealthy air system may provide unique joint war-fighting capabilities and possibilities. The MPUAV concept may have significant utility across a wide range of missions, including all-weather ISR&T, delivery and monitoring of remote sensor systems, battle damage assessment, Special Operations Forces support, jamming and information warfare support for strike missions, and armed reconnaissance.

This mission flexibility will be enabled by a modular payload capability. The MPUAV's 1,000-lb. payload capacity, stealth, and high speed make it ideal for deep, hostile airspace penetration in areas that may be defended by sophisticated integrated air defenses and for conducting high-value, time critical tasks.

Such capabilities will be separate from and complementary to those of expendable submarine-launched UAV systems. The MPUAV is a uniquely capable system concept offering unprecedented operational possibilities to a new dimension of conventional and unconventional operations-from under the sea or on the sea. The collective results of the submarine/sea-launched and recovered MPUAV demonstrations, tests, and studies to date have provided a foundation for continued development. 

Mr. Ruszkowski Jr. is a senior staff engineer and designer for Lockheed Martin Aeronautics Company. Captain Hasslinger is a former SSN commanding officer now working as a strategist for General Dynamics—Electric Boat. Dr. Robert L. Lowell Jr. is a staff engineer at General Dynamics-Electric Boat and a former SSBN commanding officer.




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