Indian Defence Review

Rising costs of Hydro-carbons, technology innovations and general inflation are an intrinsic and unavoidable part of the life cycle costs of a warship. It is evident that maritime nations will ultimately face a squeeze on their capital budgets for new military hardware. This may well be a timely opportunity for planners to examine the options available to them to control their capital expenditure (CAPEX) budgets without prejudice to their operational needs. Such a review would conclude that ships need to be designed more efficiently and their operational life increased beyond current norms. These aims can be realized if such demands are mandated by the Naval Staff. These can then be translated at the design stage and detail protocols established to ensure fleets will perform at optimum levels during their life cycle.

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Science has shown that the deterioration of marine assets is preventable and can be controlled. Ships like humans, if properly cared for, can achieve longer life spans without serious prejudice to their initial performance. In fairness, it should be noted that without updates and modernization, it is not feasible for any Warship to maintain its relative international rating during its entire life span. A brand new ship will in time slide down the ladder in the hierarchy of fighting platforms. However, this shortcoming can be corrected through a half-life modernization program which is much cheaper than “a one for one” replacement. This submission does not discuss the many options regarding modernization and updates to maintain position in the international hierarchy pertinent to the class. It will suffice to say half – life modernizations are feasible, practical and necessary.

“¦without updates and modernization, it is not feasible for any Warship to maintain its relative international rating during its entire life span.

Currently, these are now being planned and implemented very intelligently by some major Naval powers.

Lifecycle Costs: The total life cycle cost of any warship can be broken down into its sub-heads. These are the R&D, Procurement, Fuel, Personnel (direct and indirect), Support & Maintenance. The percentage breakdown of the life cycle costs for each of these subheads depends on the type of ship. There are certain distinguishing patterns that are worthy of closer investigation by Planners. The breakdown of the Life cycle percentage costs for a typical Destroyer equivalent are as follows:

The table shows that the percentage costs for Procurement and Fuel are increasing. This trend is here to stay. Fortunately, the cost of Personnel, Procurement, Support and Maintenance are within the control of the Naval Staff. Many large design Bureaus are now making strenuous efforts to reduce these linked costs to offset the increases already highlighted. Some of the factors influencing these costs are detailed in Table.

Crew: Personnel costs both direct (wages and pensions), indirect (recruitment, training and medical), fuel and initial procurement costs all increase with the size of the crew. It is therefore imperative that the crew be reduced to its bare minimum. Some Navies still have larger crews than others for near identical payloads. The need for cross training, cross utilization, sealed machinery and automation to attain crew reductions cannot be stressed enough. In today’s egalitarian World, there is little need for cleaners, cooks help and laundry-men etc onboard war-ships. Many of these trades are legacy requirements from a colonial era; a chapter that is now history. None of such personnel are found in the space station. Astronauts, both women and men many with Doctorates, are responsible like other millions for their own House keeping and general maintenance duties; a policy that an efficient Navy needs to emulate.

Experience has shown that every twenty years, marine equipment, weapons, and weapon systems are made near-redundant due to newer and lighter and superior replacements.

It should be noted that civilian air and marine transport now operate at much higher operational efficiencies with smaller crews motivated by very harsh and demanding economic realities. Similarly, businesses using cross training techniques continue to effect drastic cuts in their personnel ranks. Navies need to examine why they cannot maintain parity in productivity with their maritime and civilian counterparts. At the design stage, a life cycle total cost saving of Rupees 10m-20m can be achieved for a reduction of a single crew member as it affects many linked parameters in the costing model.

In addition to salaries, shore accommodations and pensions, Crews generate a hotel load that includes Fresh water, storage and make up machinery, lighting, ventilation, power generation, recreation facilities, canteens, wardrooms, galleys, refrigerated stores, sick bays, store rooms and pantries etc. A smaller ship requires less maintenance and upkeep since surface area is a function of the square of the length. There will also be a reduction of the “wet spaces” which means less surface exposure to the surrounding electrolytic fluid which promotes corrosion. The size of the crew must be carefully assessed at the design stage. Once the ship is in service, there are other details that need to be addressed if Navies are to attain the maximum life span of their Fleets.

Shock: Other things being equal, the principal driver of procurement cost of all systems in a warship is the shock requirement. Since these systems are contained on the platform, it is easier for specification writers to specify the same overall shock requirements for all systems throughout the platform. This inevitably leads to a closed system of design and procurement relying on specialized suppliers who enjoy a monopoly in the supply of very expensive shock hardened equipment. The majority of fast moving proven commercial equipment readily available off the shelf cannot qualify in such a process.

The shock intensity of modern weapons has been growing by leaps and bounds. The shock spectrum used by most designers does not often match the weapons the ship will face during its commission. If it takes a decade or more between concept formulation and delivery of the ship, it is certain that the next generation of weapons will have higher shock factors than are current. It is therefore not necessary to excessively proof harden certain equipment when statistics show that the survival of the entire Platform in collision or battle could be low.Navies are now realizing that costs can be drastically reduced if they very prudently incorporate technology that already exists and is used by Industry. The use of such open systems and shock limiting elastomeric mounts and shock absorbers drastically reduces cost and speeds up construction. The global trend is towards the use of Open Systems using shock isolation by mounted rafts and non-rigid wire suspension mounts particularized for each equipment rack or the compartment itself. Technical divisions responsible for detailing and interpreting the Statement of Requirements (SOR) often make unrealistic and unwarranted demands that result in extravagant costs. A serious effort to enforce Open Architecture where practical, will result in huge savings.

Service Life: Naval fleets are national assets and the Navy is the nominated custodian. Like any other business, the Navy needs to know the as designed life expectancies of its capital assets. This information is first established at the design stage. The life expectancies of warships are a subject that is gaining worldwide momentum and needs to be addressed. In the case of new construction, the expectancy should be stipulated by the Naval Staff. New carriers should have a life expectancy of fifty years. A target of up to forty years is now feasible for other sea going ships subject to the consideration that the Ship will and must undergo a half-life refit at twenty years. Experience has shown that every twenty years, marine equipment, weapons, and weapon systems are made near-redundant due to newer and lighter and superior replacements. It has also been shown that if Hull integrity can be guaranteed, it is extremely cost effective to do a half-life modernization. An unbolt or a strip and rebuild is a preferred route when budgets are tight.

With time and sustained operations in heavy weather, the paint film develops micro fine cracks allowing seawater the access it seeks. Since the exposed steel surface is not homogenous, electro potential differentials exists leading to corrosion and loss of strength.

A target life beyond twenty years cannot be achieved using the old methods of design and maintenance. It requires a new mind set. The life cycle costs of a ship are a result of decisions made at the design stage.

These costs can be grouped as visible and invisible. The invisible costs are manifest only after the ship has been built. They arise due to complexity, precision, variability in outcomes, over sensitivity, immature technology, omitted health and environmental hazards, short life spans, and excess demand of operational skills. The invisible costs due to these factors can only be quantified by experienced staff and are fairly substantial. Hence, increasing target life is a very intricate tasking that involves close review and update of the existing practices. Unlike Machinery and Equipment which can and may be fully replaced during a Half-life modernization, the Hull cannot be changed. The design and subsequent preservation of the hull are thus key elements which affect the life of the ship as a whole. The rest of this submission will discuss how this life extension can be achieved.

Corrosion Control: Corrosion control at the design stage has in the past generally been accorded little priority. The optimization of structural weight using closed spaced stiffeners with light weight plating results in hungry horse looking structures. Such designs being more elastic initially have a superior shock response. However with time, the strength of these thin plate hulls will degrade faster with corrosion which is inevitable. A light weight hull is more prone to fatigue cracks both in the preserving paint film and the joining welds. With time and sustained operations in heavy weather, the paint film develops micro fine cracks allowing seawater the access it seeks. Since the exposed steel surface is not homogenous, electro potential differentials exists leading to corrosion and loss of strength. The process is self-sustaining if not interrupted. For longer life, a stiffer hull using wider spaced stiffeners and thicker plating incorporating a small accidental corrosion allowance is far better. The resultant penalty on power and fuel is more than offset by the longevity gained.

At the design stage, the influence of long term corrosion and its correlation to the Hull strength is often overlooked due to limited data and expectations. Nevertheless, the reduction of structural weight still remains a dogmatic priority of many designers. Detailing shell structures for longevity requires special effort. Many junior civilian design staff responsible for such work, being far from the sea, are indifferent to the unrelenting electro chemistry that can send a ship to its grave prematurely. Corrosion the silent killer depends on water. Every effort to reduce the electrode and the electrolyte is necessary. The preparation, Paint schemes; passive and active cathodic protection for the surfaces in each compartment need to be very carefully examined. Humidity control using increased ventilation and De-humidifiers in wet/moist spaces are absolutely necessary to avoid condensation and contamination of Insulation. The drainage slope, scupper, downspout, and suction locations need careful review and quality assurance (Q.A) at the design stage using 3-D graphic simulators. As part of the pre painting preparation, all horizontal surfaces of stiffeners, openings and drainage ports that may retain water need to be rounded off after erection and pre lined during painting prep. A tedious task that is more often not done.Construction and Maintenance: If longevity is to be achieved, the Q.A standards of warship hull manufacture and repairs which includes survey, repair, prep and paint needs a massive overhaul. The current technology used is very deficient and is compounded by poor tooling, staging, lighting, ventilation, humidity control and lack of appropriate machinery and personnel. Poorly educated laborers, painters, fitters and platers form the bulk of the construction department trades. Ships and submarines are built with high strength steels which are expensive. During maintenance, corroded surfaces have to be stripped off paint and prepared for repainting. Very often, freshly sharpened, hardened steel chipping hammers have been used to do this. This leaves a set of notch indentations on the steel surface which reduces the strength of the original plate. The net result is a surreptitious and unplanned degradation of Hull strength which has never been documented or accounted for.

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The training, education and compensation of the hull trades and junior hull design staff have long been neglected. There is a technology gap in as much the average worker has little or no formal technical training whilst his departmental head needs a Master Of Science Degree and more. Many of the older generation of hull workers do not even have a high school diploma. Such a wide and heavily skewed spectrum of qualifications within a Department can never guarantee an extended hull life. Based on the savings to be gained, it will pay off handsomely if the construction departments are fully modernized and the compensation packages re-engineered to meet the desired goals and standards required. The use of cameras, real time computerized media recording, detail work process standards and visual training documentaries are seriously lacking. Most yards do not have a set of detail process videos detailing the various jobs step by step including appropriate tools and equipment, electronic documentation of the Q.A, Q.C standards, atmospheric controls, the monitoring equipment required and the expected productivity norms. Modern 2 coat epoxies require SA 3 prep, sponge blasting, ultra clean vacuums/wash and spot infra-red dryers.

As terrorists get more sophisticated, they will endeavor to use the sea route to move fissile materials and “dirty devices” into maritime countries clandestinely using container bound shipments.

Preparation and pre-lining of weld lines and contoured surfaces at site referred to earlier also deserves special attention. During construction, the integrity of the Module during handling, erection, welding and house-keeping must be continuously verified and recorded by qualified Technologists to ensure the integrity of the paint film, the design dimensions and layout. The cost of careful design with proper regular high performance maintenance and planned half life refits to extend the serviceable life of a hull is small compared to the costs of building a new ship.

In lieu of repair at site, “repair by replacement” and subcontract through joint partnership with the Private sector have not made much headway. Though such competitive practices reduce costs, Public and quasi public sector, unions and management, all being stakeholders, are usually unresponsive to outsourcing since it limits their growth and monopoly. Maintenance costs and down time can be considerably reduced if alternate competitive repair options are permitted and are a part of the pre-planning process. Life raft repair and maintenance is just one of such examples.

Like naval ships, all merchant ships are required to carry a set of identical Lifesaving gear under identical regulations. In times of peace, merchant fleets have a much higher operational availability and are subject to more intense economic competition, than Naval ships. Yet, the owners of merchant ships, who can afford less downtime and costs, entrust the Maintenance of their Life saving gear entirely to the Private sector. On the other hand, some Navies have insisted on expanding their owns hop facilities in the Public sector for identical work. There is little justification for that choice. An independent audit to establish the maintenance work that could be done by joint partnership between the two sectors would go a long way in reducing costs and improving operational availability.

Fire & Nuclear risk: A sustained fire on board any ship will seriously degrade the hull. Since this risk cannot be eliminated entirely, it must be carefully monitored and reduced. The need of an electronic Fire and Inflammable& Hazard (FIH) statement that lists the types, quantities and combustion end products of every flammable and nuclear Hazards on board every warship and Submarine at any instant is necessary. No Command can afford to be indifferent to such basic precautions. A guarantee of a long life span necessitates that the risk of a fire and consequential loss of strength is controlled. To achieve that, the electronic FIH statement should be kept up-to date whenever the agreed ceiling change limits have been reached. A copy should be handy and available in the Command, the Repair Yard when a ship is taken in for repairs and outside Fire fighting agencies when summoned for assistance. The Design Office has to be the initial originator for the FIH but maintenance thereafter should be the entrusted to the Ship and Command.

As terrorists get more sophisticated, they will endeavor to use the sea route to move fissile materials and “dirty devices” into maritime countries clandestinely using container bound shipments. It is therefore necessary to install smart sentinel wind/solar powered Radiation and Visual Detector Buoys to guard the channel fairway used by the ships of the command. This will enable the detection of all radio-active sources being shipped in and facilitate ships to be quarantined when necessary. Such detection should be an integral part of the Base security. The cost is small considering the possible catastrophic loss due to any contamination of the Base, the Fleet and the Port.

Salvage & Damage: Collisions and accidents do occur. These risk also needs to be adequately addressed so that the Integrity of the hull can be immediately assessed. This is best done when the Command has a specially trained Fleet Salvage and Diving Office with a Computerized system responsible for the stability, fire fighting, damage control, structural sea keeping response and underwater security of the fleet. This office should also be responsible for the visual capture of any associated damage to the Fleet, marine archeology and wrecks. It should be no surprise that such an organization in addition to its extensive Diving facilities will need a host of salvage equipment, surface and underwater vehicles. Additionally, an underwater security inspection and cleaning station and a real time panoramic visual camera system to display the state of any Hull and any corroded sites and damage to the ship and naval staff are essential.

The establishment of monthly statistics of ships in terms of Operational availability, distance sailed, wave bending Stress from stress gauge extrapolated to standard load condition also needs to be done regularly and analyzed. This information is of importance for correlating the strength of the hull with time. The cost of fitting a few strain rosettes under the Upper deck when the ship is on the ways or in dock at the time of construction is every small. Knowing the exact current load and stress, it is feasible to extrapolate the result to the standard wave Bending stress. Such data will help to establish the Command to monitor the degradation of hull strength on an annual basis thus enabling them to determine the limits of the operating envelope for different sea spectrums and damage profiles.

 If the Navy desires to implement a lasting improvement, we need to train a new cadre of hull technologists who understand the science of corrosion, surface preparation and paint.

Painting: Maintenance painting of the ships external hull done manually by brush from suspended staging under wet monsoon conditions has always been problematic. This is an expensive wasted effort which can never meet the Q. A standards of application required for modern epoxy and silicon paint systems. This is further compounded by the docking arrangements used. The use of side shores to provide a lateral constraint when the ship is in dock makes it impossible to erect any temporary shelters during painting of the ships external underwater hull. The practice of using side shores while dry docking stems from tradition; there are no side shores used when ships are launched on ground-ways.

Engineering protocol requires that the ship in dock be adequately supported against any lateral forces due to the hundred year maximum Seismic Earth quake/wind Loads for the zone, and the maximum unanticipated and unaccounted load shifts during refits. These transverse loads can be adequately supported by a set of anchored side blocks which then makes it practical to dispense with the side shores. If the ship sides are clear and accessible, it is then feasible to utilize power activated mobile screened staging between the ship side and the dock side to provide dry conditions during external painting. With the use of such mobile staging, infra red industrial heaters, fans and mobile controlled powered manual or robotic cleaning and spray painting machines, it is feasible to repaint a degraded epoxy surface to specification by locally isolating the Hull from the monsoon like weather. To do this, there must be adequate clearance of the ship in dock.

The older dry docks were designed for narrower ships with smaller Beam to length ratios. In recent years, this ratio has increased resulting in ships with wider beams. Because of this, the clearance of ships in these older Docks is often extremely small. Clearances of 4-5m, 10m and 2 meters for the side, tail and head respectively are absolutely necessary for good access by the maintenance teams. If external bottom painting is done correctly using current technology and use made of mechanical underwater robots for gently cleaning the slime film periodically, the dry Docking interval can be increased to at-least six years and more. To achieve this, it is also necessary that ships alongside do not berth in polluted shallow water. Such sea water being warmer adds to the fouling and corrosion threat. Sea water that has lower temperatures and is more neutral is preferable. This can be achieved if harbor dredging both capital and annual are planned and integrated into the overall requirements.

Conclusion

In some countries, maintenance has never been very popular or readily accepted as a necessary pre-planned expense. As proof, as one travels around, one has to look around at the variation in visible rust stains & cracks on buildings, trains, buses, vehicles and coastal ships. Hiding a rusted surface by a cosmetic coat of paint, as is often done before a VIP visit, is not the solution. If the Navy desires to implement a lasting improvement, we need to train a new cadre of hull technologists who understand the science of corrosion, surface preparation and paint. Since it is impractical to have a dual set of new and old maintenance standards, I hope that the younger generation will embrace the genesis of a new standard which will maintain and guarantee the operational integrity of our ships and public infrastructure against the ravages of corrosion, wear and tear.

If there is a total commitment to the systemic change suggested, it is feasible to increase the operational availability and extend the life of our ships hulls by at-least 25 percent and more. However, that will require a massive reformulation and training of the “construction” departments in both private and public shipyards and an investment in modern hull maintenance techniques, personnel and equipment. This expense will be miniscule compared to the improved readiness and longevity gained by the ships of the Fleet and the reduced CAPEX that will eventually follow. In addition, their survivability with age against fire and damage due to Action or Collision will undoubtedly also be better than ever before.