Conserving Fuel at Sea
By Commander Glenn P. Kuffel, Lieutenant Commander Barry Palmer, and Lieutenant Commander Mary Katey Hays, U.S. Navy
Volatility in the global oil market has resulted in extreme cost fluctuations for F-76 Diesel Marine Fuel (DFM). Over the past year, the quarterly costs for DFM to the U.S. Navy have varied from $70 to $170 per barrel.1 With annual fuel bills routinely in the billons of dollars and cost estimates unpredictable, fuel conservation is no longer an option to be considered; it is an operational imperative. By collectively managing our fuel costs through conservation at the unit level, force and Fleet commanders can have greater flexibility keeping the Fleet at sea and not consider reducing underway-training days. Here we address only Arleigh Burke (DDG-51) class guided-missile destroyers, but many of the suggestions apply to all ship classes.
Engine Selection
Main Engines: An Arleigh Burke DDG has four General Electric LM 2500 gas turbine main engines for propulsion, with two engines per shaft. One engine alone is sufficient to propel the ship at greater than 15 knots.
It may seem intuitive that each main engine burns fuel at the same rate, but this is not the case. The main engines consume fuel at different rates for a variety of reasons. Age, compressor blade wear, fuel pump efficiency, and combustor efficiency among others affect an engine's performance. Considering engine selection, while balancing engine hours, may yield cost savings.
Gas Turbine Generators: Flights 1 and 2 Arleigh Burkes have three Allison 501K gas turbine generators. The minimum requirement during underway steaming is two generators placed online and in parallel, both powering the electrical bus. Like the main engines, each gas turbine generator has a different burn rate to maintain the required electrical output. Considering which generators to operate, while balancing hours, may also yield a cost savings.
Maintenance Matters
On both the main engines and generators, one of the simplest ways to ensure maximum fuel efficiency is to keep them clean and maintained within the planned maintenance system (PMS) guidelines. Dirty gas turbine compressor blades reduce efficiency, increase engine wear, and cause higher fuel burn rates. PMS requires water-washing a gas turbine main engine after every 100 hours of use and 200 hours for gas turbine generators. Water washes should be conducted more frequently during or after operations in dust storms or heavy seas to keep the compressor blades clean.
Beyond PMS, there are engine performance indicators, such as temperature and torque, which can be compared among engines. These indicators may reveal trends that show an engine within PMS standards but not operating at peak performance and, therefore, using more fuel. Many performance deficiencies can be corrected by adjusting the engine's electronic controls, while others may require engine component cleaning or overhaul. Fuel and repair parts are funded by separate accounts that cannot be interchanged at the unit level, but the Navy realizes an overall savings when the engines are operating at maximum efficiency. For instance, a main fuel control valve for a gas turbine main engine costs approximately $18,000. By contrast, an engine that burns an extra five barrels of DFM per day can cost an additional $10,500 to $25,500 every 30 steaming days.
Operational Engineering
Various missions require different engineering plant lineups. Generally, the greater the mission's risk, such as going alongside an oiler for refueling, the more engines are placed online. However, by carefully weighing the risks, evaluating the mission, and executing a well-briefed plan, commanding officers can conserve fuel without hazarding their warships.
Speed Efficiency: Maximum transit speeds are set by the numbered Fleet commander. However, a warship's most fuel-efficient speed depends on the engineering configuration in use and the data the engineer has for each main engine. When the mission allows, conducting voyage planning using the most efficient speed will reap fuel savings.
Restricted Water Transits: Warships routinely conduct restricted water missions with all four main engines on line and three generators operating. In 2008, the USS Carney (DDG-64) transited rivers and canals with only four engines (two for propulsion and two for electrical power generation) instead of using all seven engines. Originally, this engineering lineup was selected due to operational refueling considerations. Through well-prepared briefs and good communication between the bridge and engineering watch teams, the Carney was able to safely mitigate risks. As the data below show, approximately 407 fewer barrels were used at a savings of nearly $52,000.2
- 22-hour round-trip Suez Canal transit: 122 barrels conserved, $15,494 saved.
- 14-hour round-trip Delaware River transit: 200 barrels conserved, $25,400 saved.
- 6-hour round-trip York River transit: 85 barrels conserved, $10,795 saved.
There are times, during river and canal transits, when operational risk management (ORM) requires all engines to be available. During the Carney's Suez Canal transits, all seven engines were started and on line as necessary before arriving at the entrances due to time of arrival and traffic density. Two main engines and one generator were secured once inside the canal.
If warships routinely conduct restricted water transits with the minimum engines required, and as operations permit, the Fleet can achieve a significant cumulative fuel savings.
In-Port Single Generator Operations: During overseas deployments and U.S. port visits, shore power is rarely available for a warship's use which requires generators to remain running. Routine operations in port can be conducted with one gas turbine generator until additional amperage is needed for pre-underway equipment material checks. On the Carney, engineers observed a daily fuel savings of 30-40 percent, with a daily burn rate of 1.2 to 1.8 percent total fuel capacity when operating on a single gas turbine generator versus two.
Special Evolutions: Warships conduct a range of special evolutions at sea, including underway replenishment, helicopter operations, small boat launch and recovery, passive sonar tail streaming, torpedo countermeasure tail streaming, and aircraft carrier plane guard. ORM for some of these, such as underway replenishment, demands the maximum engineering redundancies be available without delay. But for many others, a close study of ORM will provide the commanding officer with the confidence to conduct special evolutions with one to two main engines online and two gas turbine generators. The seas, winds, time of day, crew proficiency, watch station manning, and commanding officer's standing orders are all to be considered.
Drift Operations: When under way without a suitable anchorage nearby, and as the mission permits, it's okay to turn off the main engines and drift. Warships should consider the timing of this carefully, however. For example, during the nightly ebb in the unit-level training phase, drift operations should be routine, versus steaming in a confined "box" the navigator has designated on the chart.
Overtime Port Operations Costs
To minimize overtime costs, routine operations in homeports are conducted during established time periods. Any deviation requires approval by the type commander via the immediate superior in command.
Again, funding sources do not align. U.S Fleet Forces Command pays for fuel from a centrally managed account. Port costs, including overtime, are paid by the Commander, Naval Installations Command. Money spent for an early departure or late arrival is not viewed as a fuel savings, but as a loss due to overtime costs. The comparative costs are hundreds of dollars in overtime versus tens of thousands in fuel.
It should be simple to tie fuel savings to any overtime cost. But this requires cooperative staff work. When staffs make overtime approval a "bridge too far," commanding officers are forced to make speed and burn fuel to make commitments or pilot pickup time. This preserves the overtime funding lines—and incurs a far greater fuel cost.
Clearly some of these recommendations will test commanding officers' comfort levels, and fuel conservation should not be a consideration when an operational requirement demands speed. Training should never take a backseat, either, as commanding officers must run their ships through the paces of full power runs, tactical high-speed maneuvers, and junior-officer development.
For the time being, there is no technological alternative to fossil fuel for powering our warships. We must use this resource wisely as missions and operations permit. It is doubtful that fuel oil costs will significantly decrease; we should prepare for larger bills. But by collectively conserving, we may be able to hold the line and perhaps even reduce overall fuel costs. Doing so will preserve our underway-training days and operational tempo.
1. Hasan Pehlivan (manager of energy conservation, Naval Sea Systems Command), e-mail to authors, 31 March 2009.
2. Calculations assume a transit speed of 10 knots for the Suez Canal and 15 knots for the Delaware and York Rivers, and do not account for speed changes in the course of routine navigation. Savings are based on a cost of fuel at the time of transit, which was $127 per barrel. At $170 per barrel, the following the savings would be realized: Suez Canal, $20,740; Delaware River, $34,000; York River, $14,450.
Four Questions Simplify the Use of Force
By Commander Andrew J. Norris, U.S. Coast Guard
Small units typically conduct Coast Guard PWCS (ports, waterways, coastal security) missions, including harbor patrols and vessel boardings and escorts. They are commanded by very junior personnel—vested with the authority and responsibility to make some of the most difficult decisions a military commander must ever make. For example, if a small boat approaches an escorted nuclear-powered submarine at high speed, violating repeated warnings and a published no-entry zone around the sub, the unit commander must correctly assess whether terrorists or irresponsible teenagers are at the helm. This commander then has to decide—instantly—how to respond lawfully and appropriately if it is determined that the boat is operated with evil intent.
I refer to this latter decision as the response determination. It is controlled by two doctrines: the Coast Guard Use of Force Policy (CGUOFP), and the Standing Rules of Engagement (SROE).1 Each of these is complex in its own right. The CGUOFP intersperses a number of broad principles with some specific provisions, such as four ways of classifying subjects against whom force is being applied, six levels of force that may be used against an individual, and four steps that can be taken against non-compliant vessels. Similarly, the SROE require an operator to understand not only broad principles but also such precise terms as self-defense, necessity, proportionality, hostile act, and demonstrated hostile intent. The doctrines pose interesting and vexing questions about how they interrelate and which one applies when.
Classroom-style training focuses on teaching and testing the details of each policy and their relationship to each other. Such training is necessary, but does not go far enough. To foster appropriate response determinations in fast-moving, confused situations, trainers must lead operators beyond memorization and recitation, to a state of internalization. This requires training that simplifies complex concepts and reflects the thought processes in which operators will engage.
Fortunately (and surprisingly), the SROE and CGUOFP can be boiled down to four bedrock principles that foster internalization. They are simple to understand and geared to the mental state in which operators will be at crunch time.
Is a Threat of Death or Serious Injury Imminent?
PWCS operators always have the right to use force, including deadly if necessary, to defend any person who faces an imminent threat of death or serious physical injury. This rule applies whether the threat is to a military unit, sub-unit, or personnel; or to civilians, infrastructure, or hazardous materials.
For all of those but a threat to civilians, both the SROE and CGUOFP authorize the unit commander and personnel to use all necessary force, including deadly, in response to a hostile act or demonstrated hostile intent. In addition, the CGUOFP permits the use of force, up to and including deadly, in individual self-defense when the service member has a reasonable belief that there is an imminent threat of death or serious physical injury to the officer or another person.2
The SROE typically apply only in the context of defending military assets and personnel; not to defending civilians.3 But the CGUOFP states in section B.3.b. that deadly force may be used against persons and/or vessels posing an imminent threat of death or serious physical injury to any person. Possible situations include one vessel threatening another; theft, sabotage, unauthorized control, intentional damage, destruction of hazardous materials or deadly weapons; and threatened damage to or destruction of critical infrastructure such as locks, bridges, and power plants.4
The SROE and the CGUOFP use different terms to describe the trigger for these uses of force: "hostile act" or "hostile intent" in both, "imminent threat of death or serious physical injury" in the latter. In a perfect world, operators would be able to distinguish the subtle differences, if any, between these terms in a fast-moving, confusing, adrenalin-laden situation.
But in the real world, that is expecting too much. Since a hostile act or demonstrated hostile intent equates to an imminent threat of death or serious physical injury, in the interest of simplification and internalization, only the CGUOFP trigger for use of force in defense of life should be emphasized in the PWCS context.
Is the Law Being Infringed?
Operators always have the right to use non-deadly force to compel compliance with the law or lawful orders. The CGUOFP (and other rules) permits the use of non-deadly force to enforce the law.5
Chapter 4.D of the Maritime Law Enforcement Manual prescribes a continuum of force that can be used to compel a vessel's compliance. Chapter 4, section B.3.a, permits the use of non-deadly force to enforce a lawful order, prevent a federal crime, effect an arrest, or prevent an escape. If the subject of an order acts in a manner that imminently threatens death or serious physical injury, the rules under Question 1 apply.
If There Is Flight, Is There Danger?
Operators may use deadly force to stop a fleeing subject only if: (1) there is cause to believe the person has committed a violent felony; (2) the person poses an imminent threat of death or serious injury; (3) the subject has been warned.
Simplifying this situation is difficult, because in some ways it is an exception to the non-deadly provisions of the previous question. This situation is not unique to the Coast Guard; it derives from the Supreme Court's ruling in the case of Tennessee v. Garner, 471 U.S. 1 (1985), in which a police officer killed a fleeing burglar with a single round to the skull. It turned out that the burglar was a 15-year-old eighth grader who had stolen ten dollars and a purse.
The court ruled this to be an unreasonable use of force and came up with detailed prerequisites that must be satisfied before a law-enforcement officer can use deadly force to stop a fleeing suspect. The Coast Guard incorporated these into the CGUOFP.
Is This Level of Force Reasonable?
Whenever operators use force, they may use only the level that is reasonably necessary for the purpose. In CGUOFP terms, only force that is "reasonably necessary under the circumstances" may be applied. Excessive force may never be used.6
Reasonableness under the SROE means force "proportional" to the threat. That is, force must be sufficient to respond decisively to a hostile act or demonstrated hostile intent, but not excessive in terms of its nature, duration, or scope.
As with the threat determination in Question 1, the doctrines governing use of force employ different terms to prescribe the lawful level that may be applied. Since "proportional" means the same as "reasonably necessary under the circumstances" and not "excessive," we can and should use a single standard—the CGUOFP's—in the PWCS context to meet the criterion of reasonableness and promote internalization.
As a whole, these four questions reflect the fundamental principles of both of the use-of-force doctrines governing Coast Guard PWCS operations. Notwithstanding the nuances and intricacies, a PWCS operator who has internalized them will be eminently suited to respond to the ultimate nightmare scenario: having to make an instant threat and response determination in or around a port in the United States.
Memorization and recitation do not serve an operator well in such a situation. The person must have internalized the applicable principles long before then. Trainers can facilitate internalization by simplifying issues and focusing on thought processes. Teaching personnel to ask these four questions, in conjunction with traditional classroom training, is a way to achieve this.
1. The CGUOFP is set out in the Maritime Law Enforcement Manual (MLEM), Commandant Instruction M16247.1D, Chapter 4. Personnel must adhere to this while conducting missions and engaging in self-defense (MLEM at 4.B.1). For the SROE, see Chairman, Joint Chiefs of Staff, "Standing Rules of Engagement/Standing Rules for the Use of Force," CJCSI 3121.01B. The SROE apply to Coast Guard units, wherever located, that determine they must take action in defense of themselves or other U.S. forces in the vicinity, even if that need arises while the unit is engaged in a Coast Guard mission (MLEM, Chapter 4, section E.1).
2. MLEM, Chapter 4, section B.3.b.1.
3. U.S. persons and property, and/or U.S. commercial assets may be defended as an exercise of national self-defense; special authorization is required for such a use of force. See SROE, Enclosure A, section 3.b.
4. See MLEM, Chapter 4, sections B.3.b.4. and B.3.b.5.
5. See 14 USC 89, which permits qualified Coast Guard personnel to use all necessary force to compel compliance with law-enforcement-related activities.
6. MLEM, chapter 4, section B.2.
Improving FleetTac and DivTacs
By Captain Robert Oldani and Lieutenant Richard Eytel, U.S. Navy
What has become of our proficiency in tactical communications and divisional tactics? In the not-too-distant past, both were staples of the surface warfare community. We set the standard for other navies. Sadly, almost two years of underway operations with ships from different navies have convinced us that today, tactical communications lack professionalism, and divisional tactical maneuvering exercises (DivTacs) are sloppily executed.
A short time tuned in to the Fleet Tactical Maneuvering circuit (FleetTac) will expose the alert listener to a multitude of common communication mistakes. These include not answering signals in alphanumeric order of call signs, units transmitting over one other, improper use of immediate or delayed executive methods of executing action signals, passing information signals via an executive method, and double call-ups.
FleetTac communications and shiphandling continue to be important as ships operate in close proximity in littoral waters, during counter swarm tactics formations, and in providing escort defense operations. Sloppy practices may accomplish the intent, but they are unsafe and a poor reflection on surface ship operations, pride, and professionalism. Additionally, as U.S. Navy ships operate with coalition partners, the use of formal communications, predictable in their cadence and format, and understandable in their standard nomenclature, make communications more effective and avoid a sea of "say again" requests.
We can do better. Excellence in operations demands proper use of established procedures. A thorough understanding of the Allied Maritime Tactical Signal and Maneuvering Book (ATP 1, Revision D, Volume 2), a firm grasp of fundamental communication procedures as guided by the Allied Communications Publication (ACP-125[F]), and a developed sense of shiphandling characteristics are necessary to get this right. It is time to improve FleetTac and DivTac proficiency!
Communications
Know the Rules: ACP-125(F) is an underused but valuable guide and text. Chapter 4 on discipline, chapter 6 on operating rules, and chapter 7 on the executive method constitute a clear tutorial on proper radio procedures. As is the case with so many references, use of this publication provides knowledge and confidence to the user, and reduces the need for locally produced gouge sheets.
Order of Call Signs: Alphanumeric. In accordance with chapter 6 of ACP-125(F), Fleet units are to respond to signals in alphanumeric order, not the order of the column, seniority, or any other random order. This simple, basic rule is seldom followed. Following a specified order avoids stepping on one other and repeated calls for "did you copy my last?"
Double Call-Ups: The Fleet Tactical circuit is guarded. Therefore, separate call-ups are unnecessary. Keep FleetTac communications short, crisp and formal, and avoid double call-ups.
Action versus Information Signals: It is clear that we have a gross misunderstanding of the difference between information signals and action signals in the Fleet. Action signals are clearly identified in the signal book and should be passed using either the immediate or the delayed executive method. When in a line or column formation, guide movements such as speed changes, turns, and so on are action signals. Conversely, information signals such as base course, base speed, and guide's movement when in a screen formation, are merely for the information of all. These should not be passed with an executive method.
The formats for the two executive methods are different and often interchanged, which can lead to confusion on exactly when to execute the change. The following is an example of an action signal executed by the immediate executive method: "L0N, T1N, 1XO, this is CO1, immediate execute, speed one, two, I say again, immediate execute, speed one two, stand by . . . [un-key the microphone for three seconds] Execute, over." The other units would then roger out in alphanumeric order.
Alpha Station: While there is no ATP level directive on when "Alpha station" shall be used to signal a ship's position, many commanders have decreed that its use is neither required nor desired. Alpha station is an unnecessary signal, as the officer in tactical command already possesses the necessary resources to determine ships' positions. Additionally, watchstanders can be pressured to report Alpha station early, confusing the tactical picture.
Accuracy, Brevity, and Clarity: The age-old guidance of the ABCs of communication is always applicable. Bridge teams should practice their communications with each other to avoid nervous chatter and the long, unprofessional pauses so commonly heard.
Lack of Knowledge of ATP 1(D), Volume 2
We need not memorize signals from the book, but most watchstanders have insufficient knowledge of the information in ATP 1(D), Volume 2. They must thoroughly understand the general instructions of chapter 1 and be familiar with the details of the signals in the remaining chapters.
Turn versus Corpen: Another very basic concept that seems to trouble inexperienced watchstanders is the difference between a turn and a corpen. The memory aid "turn together true" can be used to reinforce the idea that upon execution of a turn, all ships turn at the same time to the new course, maintaining the same true bearing to the guide. Upon execution of a corpen, the formation stays the same, and ships have the same relative bearing to the guide upon completion of the maneuver.
Automatic Changing of the Guide: How often are signals passed confusing bridge teams on which unit is the guide? Too often. Chapter 1 specifies a finite number of occasions when the guide automatically shifts upon execution.
Ships in a column "exchanging station" is a different maneuver than "reversing the order of a column." This distinction is important, as the guide shifts may be different. Similarly, a ship taking a new station in front of the formation is not "the ship being formed on." And the guide never shifts when executing a turn, except for a search turn, which is really a corpen maneuver. All shiphandlers need to know and understand these automatic shifts to safely maneuver ships at sea.
Basic Shiphandling Skills
Maneuvering board proficiency is a necessary skill for quickly obtaining a solution of course and speed to get to station. The advance of electronic navigation and radar systems has made it easy for watchstanders to lose this important skill. Basic maneuvering board skills should be exercised on a regular basis in order to stay proficient.
Inexperienced shiphandlers have difficulty maneuvering at the correct time to get on station, and are not aggressive enough in quickly regaining station once they realize they are off. Conning officers should work aggressively to attain and maintain station.
When determining whether a ship is on station, the distance between ships in a line is measured between foremasts or navigation bridges. Bearing should be shot to the approximate position of the other unit's centerline pelorus.
Effective maneuvering requires cohesion between bridge watchstanders, and between the bridge and the Combat Information Center (CIC). The bridge team should be augmented with additional watchstanders dedicated to certain tasks.
The operations specialists and the CIC watch officer should pass their signal interpretations and maneuvering solutions to the bridge and provide forceful backup as required.
Ten Rules to Improve Tactical Communications and DivTacs
- Learn and understand ATP 1(D), Volume 2 and ACP-125(F).
- Call up and answer in alphanumeric order.
- Send action signals using one of the executive methods.
- Don't send information signals via an executive method.
- Review the difference between turns and corpens, and know when and how the guide automatically changes.
- Augment the bridge and CIC teams with additional qualified watchstanders.
- Frequently practice communications and DivTacs between the bridge and CIC.
- Conduct internal shiphandling training with watchstanders.
- Keep training dynamic. Plan and execute meaningful and exciting DivTacs sessions that maximize automatic changes of the guide, and include numerous signals with short times to station.
- Do not tolerate substandard communications on any external or internal nets.