Papers & Publications

The Future Naval Battlespace & Implications for Key Enablers

SKARDA, R. (Steller Systems), BOLTON, M. (MTWB Consultancy), TALL, I. (Royal Navy).

The impact of ongoing global events, from AUKUS to increased tension in the straits of Taiwan, South China Seas and Baltic, highlight profound changes in the global strategic context that places the maritime domain at the heart of efforts to maintain freedom of trade and manoeuvre. Globalisation means the Sea Lines Of Communications (SLOCs) are vital to the economies of the world, pressure on natural resources and climate change will mean contests in the world’s Seas and Oceans will escalate including asymmetric and semi-deniable (grey zone) attacks alongside more traditional blue water peer to peer naval combatant operations and humanitarian aid requirements. The future Naval Battlespace is hard to predict with the rate of technology change, it is safe to say that uncrewed vehicles, drone swarms, Artificial Intelligence (AI), powered autonomous elements, low observables, hypersonic weapons, Directed Energy Weapons and cyber capabilities will all feature, requiring the structure and composition of naval forces to evolve rapidly. Energy usage and the maintenance of freedom of manoeuvre through energy supply and resupply will be critical. Many of these threats are also opportunities and through pursuing these opportunities the threat will be better understood and mitigated, but economic balance must also be pursued. The paper will look at the Platform, Marine Engineering and Combat System aspects that will need to develop in order to enable improved effectiveness in the future battlespace and will draw out key threads that should lead to virtuous cost-effective development cycles to prepare naval forces for the future. Uncrewed vehicle launch and recovery, survivability, operability, modularity and reduced crewing are themes that will be looked at in the platform. Future fuels and energy management, environmental performance and availability will be considered through the Marine Engineering aspects and the Combat Systems will cover future effectors, network enabled capability, sensor integration, open architectures as benefit and threat, operator workload and combat system automation. Cross functional aspects will be explored such as the future of survivability, management of damage control in lean manned and autonomous vessels, automation of currently manpower intensive operations and how this may affect personnel and organisational structures.

Link to paper

Implementation of A Novel Federated Approach to the Analysis of Sinking Ships

GODDARD, R. (Steller Systems), SCHOFIELD, J. (Survivability Consulting Ltd), GLIDDON, P. (Steller Systems), MENZIES, D. (Survivability Consulting Ltd), MARSHALL, S. (UK MOD), THOMPSON, H. (Steller Systems)

This paper presents a summary of the development activities undertaken as part of the refinement and implementation of a new, federated analysis of sinking ships first presented at INEC 2020. The described approach uses a functional survivability analysis as the basis to generate a time domain sinking ship assessment and subsequent escape and evacuation analysis. The result of this approach is a time to sink based on a realistic input threat against which an escape time is generated using the same damage inputs and taking account of the environment and damage induced restrictions in the flow of evacuees. The approach is designed to replace fixed and empirically derived escape criteria with realistic scenario-based assessments which cover the range of likely threats leading to abandonment. The methodology used leverages state of the art escape and seakeeping software using a survivability software model at its core. Results are driven by a large number of inputs for each software stage, all of which determine the complexity of the input modelling required and the processing time of the analysis. A sensitivity study has been conducted on an in-service Royal Navy platform and the results are summarised. The impact on assessment implementation is then discussed. The practicalities of using the methodology to conduct whole ship assessments of naval platforms is further discussed. Through the conduct of this most recent study, a number of advancements and opportunities have also been identified and are presented.

Link to paper

Bringing the Naval Inclining Experiment into the 21st Century

PAYNE, G. (Steller Systems), GODDARD, R. (Steller Systems), GLIDDON, P. (Steller Systems), MARSHALL, S. (UK MOD)

The concept of using inclining experiments to calculate the Vertical and Transverse Centre of Gravity (VCG and TCG) of a ship has been in place since the late 1700s. Whilst the form of current inclining experiments differ greatly from these early conceptual approaches; they still rely on a long-standing classical method to calculate the results. The classical method assumes that the ship is wall sided – an assumption that, in the modern day, does not need to be made. This paper utilises new, more accurate methods formulated by (Karolius, 2018) and (Dunworth, 2015) and compares them to the classical method. In order to understand their reliability and practical advantages and their applicability to the naval vessel hull form, a large number of past naval vessel inclining experiments have been reassessed utilising the two new methods. The results have then been compared to the classical results that were originally calculated at the time of inclining. This paper discusses the differences and practical benefits of these new methods alongside their potential to simplify the inclining experiment process. The work considers these factors for a range of naval platforms and makes recommendations as to how the methodologies are best applied to different types of naval vessel. Further work and future possibilities to improve the inclining experiment result accuracy further are also outlined.

Link to paper

The Future Warship – A Scoping Study

LYNN-RODGERS, A. (Steller Systems), POTTER, A. (Steller Systems), GLIDDON, P. (Steller Systems), PEARSON, D. (Steller Systems), PARDOE, A. (Steller Systems), GODDARD, R.

The current maritime defence sector is held back by a risk averse attitude to technology uptake. This is starting to change in the use of autonomous systems, however this is at the expense of other more wide reaching technologies. In this paper several promising technologies are applied to a frigate design dubbed E-SPARTAN, and their effect compared to a baseline frigate concept, SPARTAN. The designs are then compared across key metrics such as capability, sustainability, through life cost and stability. The technologies investigated were the large-scale adoption of composites and sustainable propulsion options based on an IFE propulsion system. Through rules based structural design the use of composites was demonstrated to save at least 50% of the structural weight in a like for like comparison, equating to up to 22% of lightship. This weight saving facilitated the increase in mass of the IFE propulsion system, in addition to a 240t battery bank to allow peak shaving and silent running. Alternative fuels were investigated and biodiesel was found to the most effective alternative fuel, increasing engine performance whilst being a sustainable product, producing low emissions and facilitating the use of MDO in operational areas where biodiesel is not available. Other commonly discussed alternatives such as batteries and hydrogen were found to require too large a storage volume and/or mass to be viable for the existing mission profile. The vessel operating costs were shown to be less than the equivalent conventional frigate, this is due to a reduction in non-attributable growth, a reduction in hull maintenance and the flexibility of upgrading an IFE solution. Overall the changes gave additional capability, with added design and operational flexibility, both key to a cost effective general purpose frigate (GPF). The structure requires less maintenance, due to a reduction in fatigue and corrosion. The build would be more technically challenging, requiring upskilling of the workforce for composite construction, however with life cycle savings circa £21.5M. The proposed changes constitute a stability improvement due to a lower center of gravity and the opportunity to locally optimize the layup and materials to improve survivability and signatures. The design provides additional capability due to signature reduction and silent running, both key for central frigate roles such as mine counter measures (MCM) and anti-submarine warfare (ASW), as well as providing additional sustainability credentials and facilitating operation in emissions controlled areas. The authors conclude that the implementation of such a radical concept would entail upskilling of the ship construction workforce, but the benefits of such a solution are seen across capability, flexibility and through life cost when considered over a class of vessels.

Link to paper

A Novel Approach to the Analysis of Sinking Ships: Combining Vulnerability, Stability and Escape & Evacuation Simulations

GODDARD, R. (Steller Systems), SCHOFIELD, J. (Survivability Consulting Limited), MENZIES, D. (Survivability Consulting Limited), MARSHALL, S. (UK MOD), THOMPSON, H. (Steller Systems)  15th International Naval Engineering Conference and Exhibition (INEC), 2020

At present naval ship ultimate stability, Escape & Evacuation (E&E) analysis and operator guidance are largely produced independently. Carpet plots are calculated quasi-statically giving estimations of vessel likelihood of survival using delineations of “poor stability” and “vessel lost” to the command. The definition of poor stability does not account for the dynamic effect of sea states on vessel motion. With advances in the software used to model threats and resultant ship damage effects, a new approach is proposed whereby E&E is modelled as a ship function in a survivability analysis. By integrating and automating this analysis with state-of-the-art E&E and seakeeping software, an ultimate stability carpet plot is produced giving times to sink based on time domain seakeeping simulations. In parallel, escape times are generated including the effects of flooding and ship motions on movement of personnel which are then compared to the calculated sinking times. Through a combined consideration of threat, flooding and ship motions the escape arrangements of a vessel can be improved. It is possible to conduct this combined analysis in a cost and time efficient manner through the use of the tools developed as part of this work.

The Autonomous Machinery Design of Tx Ship

EDGE, W. (Steller Systems), FIELD, C. (Rolls-Royce), WALSH, K. (Thales UK)  15th International Naval Engineering Conference and Exhibition (INEC), 2020

Today’s naval platform procurement processes are dominated by both fiscal and manning pressures that result in lean and ultra-lean-manned technologies being integrated into vessel design. Concurrently there has been huge advances over the last 5 years in ‘systems automation’ and platform autonomy. The vessels that make up tomorrow’s navies will be a force mix of manned, un-manned, or ‘optionally-manned’ platforms.

The Transition Ship (Tx Ship) is a Thales concept for the future development of naval warfare: an optionally manned trimaran that introduces the option of unmanned warships whilst retaining the alternative of keeping the man-in-the-loop during early maturation of its systems. The design showcases the benefits of optionally manned assets and offers commanders a flexible platform for anti-submarine warfare, mine countermeasures or intelligence gathering missions, with its technologies also helping reduce manning on conventional ships through state-of-the-art sensors and effectors.

Critical to realising optionally manned vessel operation is fully autonomous management and control of the ship’s mission systems and machinery systems. A manned Engineering Department traditionally keeps the vital systems on board available enabling Command to fight the ship, these include monitoring the performance of machinery system for extended periods, routine equipment maintenance and battle damage control. On Unmanned Surface Vessels, these functions are still very relevant but now need to be undertaken without humans onboard.

This joint paper by Tx Ship consortium members Thales, Steller Systems and Rolls-Royce, discusses the design practices surrounding power and propulsion system and auxiliary systems design considering the lean manned and unmanned missions. Central to this is the selection and optimisation of these systems with respect to availability, rather than more traditional metrics in order to enable the unmanned mission. These systems are fully integrated with the autonomous machinery controller which operates the marine systems in support of the vessel’s mission and calculates the vessel capabilities and impact of health events to assist with mission planning. The control, maintenance, and battle damage concepts designed for Tx Ship’s Marine Engineering systems address the unique challenges of supporting unmanned vessels and contribute to the vessel’s unique autonomous mission capability; these challenges will be outlined in this paper.

Large Naval UUVs – Navigating Between Simple and Very Complex

HARRIS, K. (Steller Systems), PAYNE, G. (Steller Systems)  15th International Naval Engineering Conference and Exhibition (INEC), 2020

There are a wide range of Unmanned Underwater Vehicles (UUVs) in operation today and they already include a vehicle with 45te displacement. Technology developments in underwater communications, autonomy, and battery and power systems, driven in part by the automotive industry, mean that many previously perceived barriers/blockers can be overcome, and underwater capability opportunities realized.

These opportunities include distancing operators from threats, reducing cost, but also reducing manpower requirements for mundane operations. Many nations require these roles in territorial waters, the extended neighbourhood and expeditionary operations. This and payload requirements conspire to drive future vehicles into a less well understood design bracket between current small UUVs and manned diesel-electric submarines.

This paper describes some of the resultant Large UUV design challenges and opportunities such as shorter development cycles, the risk of an unstable design space between relatively simple expendable UUVs and very complex manned submarines, the need for reliability and applicable rules and standards. It describes a design methodology that applies light-touch system engineering principles to vehicle concept development to address these challenges. This is supported by development and description of an illustrative Large UUV design which provides a good balance of cost, complexity, and capability.

The High-Capacity Expanding Lifeboat HiCEL – Meeting the Modern Search & Rescue Challenge

WRIGHT, J. (Ministry of Defence), PAYNE, G. (Steller Systems)  14th International Naval Engineering Conference and Exhibition (INEC), 2018

The Mediterranean migrant crisis has resulted in the highest population displacement since the Second World War. In 2016 alone, over one million made the journey across the sea. Since 2013 over 15,000 have died as a result of this journey. Small vessels such as wooden fishing boats and RIBs are commonly used by smugglers as transport. These are often unseaworthy and filled with numbers of passengers far exceeding their intended capacity.

When failure occurs, rescues are typically conducted by the nearest available vessel. These vessels are often ill-equipped for a large-scale Search and Rescue (SAR) operation making it highly dangerous for all involved. The size and quantity of lifeboats available are often insufficient for the large numbers of people to be rescued; as a result, repeat journeys are required, making the rescue process slow, inefficient and hazardous.

This paper outlines a novel solution to this problem. A concept design is presented for a rapidly expandable lifeboat capable of holding large numbers of passengers, whilst still fitting into the operational envelope of common davits. The unique inflatable design can be deployed quickly from a range of vessels and aeroplanes offering an immediate platform from which disembarkation onto a suitable vessel can be achieved. CONOPS are outlined along with the required capabilities of the design. Drop stitch technology is identified as a viable means of manufacturing the large inflatable platforms.

Finally, the paper discusses an alternative solution, retrofitting existing enclosed lifeboats with the solution to offer a more cost-effective alternative.

Link to paper (IMarEST members only; alternatively please contact us for a copy of the paper)

Humanitarian Operations:  Not a Grey Area

GODDARD, R., HORNER, D., PEDDER, S., PIPKIN, C.   13th International Naval Engineering Conference and Exhibition (INEC), 2016

Responding to natural or man-made disasters forms a key part of the Royal Navy’s (RN’s) remit, deploying its highly skilled workforce to deliver aid, provide life-saving equipment, restore infrastructure and conduct evacuations and repatriations. Currently humanitarian operations are conducted by a variety of RN vessels, drawing upon the skills and adaptability of their crew. However the vessels, which are designed primarily or exclusively for military operations, are required to operate outside of their design intent and so provide a sub-optimal humanitarian response; furthermore, conducting humanitarian operations prevents the vessels from conducting military duties and interrupts their operational programmes.

With both the overseas aid and Ministry of Defence (MOD) budgets under increasing scrutiny, it is important to ensure that both are being used in the most effective manner; can more be achieved using a different approach? The provision of dedicated Humanitarian Operation Ships (HOS) has the potential to offer a more targeted and efficient response to this core aspect of naval operations, whilst providing a range of other benefits.

This paper draws together arguments for and against the development of one or more dedicated HOS, and discusses the requirements for such a vessel type and potential operating models. The financial implications of this approach are estimated, based on the cost of recent humanitarian operations, to demonstrate that such an approach is financially viable.  Finally, a concept design for a HOS is presented in order to demonstrate how the benefits outlined above can be realised.

Link (members only)

Small Combatant Accidental Damage Extents

GODDARD, R., HORNER, D. , MARSHAL S.  14th International Ship Stability Workshop, 2014

A cost benefit analysis has been conducted to understand how the extent of transverse watertight subdivision as a result of accidental damage extent requirements drives vessel cost, and where the balance lies between cost of increasing survivability and cost of vessel loss. The results of this investigation suggest that a 15% accidental damage extent is appropriate for a small naval combatant.

A great deal of work has been conducted in recent years concerning the derivation of appropriate accidental damage extents for naval vessels; this work has focussed predominantly on extents determined as a percentage of vessel length. Traditionally however, small vessels less than 90 metres in length have struggled to comply with such a standard and have consequentially been certificated against an extent based on number of compartments.

This paper explores the impact on small combatant design of moving from a two compartment damage requirement to a 15% length damage extent through a series of design explorations on four current small combatants. The implication of a 15% extent is examined with regard to the respective changes in ship size and watertight definition required to achieve compliance, and corresponding conclusions are presented.

A cost benefit analysis has been conducted to understand how the extent of transverse watertight subdivision as a result of accidental damage extent requirements drives vessel cost, and where the balance lies between cost of increasing survivability and cost of vessel loss. The results of this investigation suggest that a 15% accidental damage extent is appropriate for a small naval combatant.

A great deal of work has been conducted in recent years concerning the derivation of appropriate accidental damage extents for naval vessels; this work has focussed predominantly on extents determined as a percentage of vessel length. Traditionally however, small vessels less than 90 metres in length have struggled to comply with such a standard and have consequentially been certificated against an extent based on number of compartments.

This paper explores the impact on small combatant design of moving from a two compartment damage requirement to a 15% length damage extent through a series of design explorations on four current small combatants. The implication of a 15% extent is examined with regard to the respective changes in ship size and watertight definition required to achieve compliance, and corresponding conclusions are presented.

Link (members only)

A New Approach to the Derivation of V-Line Criteria for a Range of Naval Vessels

GODDARD, R. DAWSON, N., PETERS, A.  14th International Ship Stability Workshop, 2014

Previous work has gone some way to understanding the applicability of the current naval V-lines standards to modern day naval designs by carrying out damaged vessel simulations using the CRN developed time-domain ship motion program FREDYN. The work presented in this paper seeks to further this understanding of V-lines by analysing the damaged motions of six vessel types, varying from a small Mine Counter Measure Vessel (MCMV) to a large auxiliary, and implementing a new methodology for the calculation of probabilistically derived dynamic motion allowances for heave and roll. Furthermore, analysis has been conducted in sea states up to a sea state 6 in order to understand the applicability of V-line criteria at greater wave heights and periods. This paper compares heave and roll allowances derived from the probability of exceeding water heights on the bulkheads bounding the damage in varying sea states for each vessel type, each with two damage cases at eight wave headings and at two speeds. Conclusions are drawn regarding the suitability of current criteria for vessels of varying size and design and their sensitivity to sea state.


UXV-Enabled Totally Modular Combatant

GODDARD, R., SKARDA, R.  12th International Naval Engineering Conference and Exhibition, 2014

The growing capability of unmanned vehicles requires the hosting combatant to be designed in a different way.   To keep up with the pace of Unmanned Vehicle UXV design and fielding requirements, the ship must be adaptable, modular and a flexible balance must be achieved between on-board and off-board capability in order to maintain an acceptable overall system cost. Operational Doctrine and Concepts must be entwined with the overall system design, where the system includes; people, platform, combat systems, network and unmanned systems. A totally modular approach to design, construction, fitting out, systems deployment and re-configuration enables the platform and the role to be independent. Integrated propulsion systems to enable future energy weapons to be deployed must be balanced with procurement costs and through life costs as well as maintaining simplicity in the platform yet allowing freedom of manoeuvre through good speed and long range.  Combined Engagement Capability, Open Combat Systems Architecture and the ability to cross-deck unmanned systems should allow a more cost effective and smaller vessel to provide the capability edge, where additional survivability comes from the task group network of supporting combatants and fleet of unmanned vehicles. The Steller Systems ‘Hermes’ concept shows one way that this balance can be achieved and the advantages to the operator and coalitions through making capability, platform agnostic.  The form factor of a small frigate provides the required balance between size and capability, cost and performance.  Through modular design, arrangements to support a multitude of unmanned vehicles and an efficient hybrid electric propulsion architecture, will show how the future of combatant design will be a trade between organic integrated systems, unmanned systems, open combat systems architecture, platform arrangement, platform numbers, personnel training and propulsion systems architecture.

Please contact us for a copy of the paper.

ASTELLER Polar Vessel

POTTER, A., WALLACE, A., PARDOE, A.  RINA/IMarEST Western Joint Branch Design Challenge, 2021

As part of their graduate development, three graduates from Steller System took part in the RINA and IMarEST Western Joint Branch, Young Person Design Challenge 2021. The challenge required the team to design a low impact polar vessel aimed at researching the effect marine traffic has on marine life. The vessel is equipped to investigate fields such as underwater radiated noise, seabed topography and composition, marine mammal communications and atmospheric composition, with the aim of improving current polar shipping legislation. Furthermore, the vessel can replenish remote research stations and act as a test bed for innovative technology. Finally, the Dual Fuel – Electric propulsion system provides a flexible, adaptable and risk reduced solution for self sufficient operations within the Arctic enviroment.


For more technical papers, please see our staff members’ LinkedIn profiles.

Background image: © Crown Copyright 2020