IEEE--ICET 2006 2nd International Conference on Emerging Technologies Peshawar, Pakistan, 13-14 November 2006

1-4244-0502-5/06/$20.00©2006 IEEE 285

System Engineering Approach for Successful

Completion of Low-Budget Aircraft Upgrades

Mobeen Akhtar Center for Advance Studies in Engineering (CASE)

Islamabad, Pakistan mobeen_engg@yahoo.com

Abstract: The Air Forces of developing countries are

constantly under pressure to upgrade their aircraft

systems. However, the exorbitant cost required for

such upgrades is the major hurdle in the undertaking

of such upgrade programs. Thus there is a need to

devise methods for undertaking these programs in a

most cost effective way.

This paper presents systems engineering approach

for handling aircraft upgrade program in an efficient

and cost-effective manner. The star analysis, life

cycle cost (LCC) and risk assessment and safety

strengthen the general system engineering approach

with respect to aircraft systems. The presented

approach draws from the experience gained from

undertaking various aircraft upgrade programs.

However, the given approach is general and

applicable for other Air Forces of developing

countries.

Keywords: System Engineering, Project

Management, Star Analysis, Chain Star Analysis and

LCC: life cycle cost.

1. INTRODUCTION

For most developing countries, longer development time, high cost and safety requirements are some of key factors to be anticipated for the up-gradation of aircraft avionics systems. These modifications are not covered under the serial production and vary from small number (may be 1) to couple of hundreds. The techniques required for such upgrades may be outdated or the systems are so old, that only outdated components fits into that system. So in such upgrades, a project management encounters many difficulties such as procurement problems, supply of tools and components, consultancy requirements,qualification and testing. Here the project management mostly overlooks one of the most important issues that even results in high cost and waste of resources in some cases. This issue is the analysis of impact of the new upgrades on

other systems of aircraft and on the future upgrades. This analysis must also include the future input requirements of other systems from this new upgrade/system. Therefore by independently upgrading the system, may results in the waste of resources and less efficiency and effectiveness of the system as whole. To avoid these problems an adequate system engineering approach has to be implemented from the beginning into the aircraft up-gradation projects.

The main goal must be to improve the overall system performance, efficiency, and quality and to minimize the life cycle cost of these upgrades to minimum. To reach this goal in a most economical way, the careful application of the following system engineering approach is recommended.

2. SYSTEM ENGINEERING

APPROACH

System Engineering is both a technical and a management process. System Engineering is an interdisciplinary approach to evolve and verify an integrated and life cycle balanced set of system product and process solutions that satisfy customer needs [1]. System Engineering is based on following:

Encompasses the scientific and engineering efforts related to the development, manufacturing, verification, deployment, operations, support, and disposal of system, products and processes,

Develops needed user training equipment, procedures, and data,

Establishes and maintains configuration management of the system,

Develops work breakdown structures and statements of work, and

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Provides information for management decision-making.

The following System Engineering approach for up-gradation can be used for better overall system performance and reliability [2]:

1. Problem definition (identification of requirements)

2. System feasibility analysis

3. System operational requirements

4. Maintenance and support concept

5. Technical performance measurers (TPMs) identification.

6. Functional analysis

7. Requirements allocation

8. System structural analysis

9. Design optimization phase

10. Design integration

11. System validation (test and evaluation)

12. Production phase

13. System maintenance and life cycle support

14. System retirement and material disposal

There is a feedback mechanism during each step for proper monitoring and improvement.

Here I propose the structured system analysis approach [3] to cope with the issue of impact of the new upgrades on other systems of aircraft and on the future upgrades for successful completion of low-budget aircraft avionics system upgrades.

3. STRUCTURED SYSTEM ANALYSIS

Structured System Analysis process includes the following main step:

Identify the operation of the existing system.

Understand what the existing system is doing.

Understand the requirements of the users.

Understand the effect of new system on other systems.

Analyze the future upgrades.

Decide new system features independently.

Decide new system features with respect to other systems.

During system analysis and design, several tools, techniques and models are used to record and analyze the current system and new requirements of users, and define a format for the future system. The major tools used in this analysis include: function diagram, data flow diagram, data dictionary, process specification, entity-relationship diagram [2].

I propose the Star Analysis technique as shown in Figure 1, for better analysis of the whole system (Inputs and Outputs from and to other systems including the future requirements). The left half of the star contains the inputs required by the new system and right half contains the outputs from this new system and the inputs requirements of other systems.

Inputs Outputs

Figure 1: Star Analysis

In Figure 1, the dotted line at left shows that the input required by this new system for its proper functioning is missing or other systems are not capable to provide such inputs. The dotted line at right shows that the input required to other systems for proper functioning is missing and this new system is not capable to provide this input. The squares contain the relevant information about other systems and their parameters.

By performing the star analysis, especially the developing countries can easily assess their system requirement as a whole and can effectively and efficiently utilize their re-sources.

New

System Input

Missing

Output Requirement

Missing

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Life Cycle

to

Life Cycle

Costs

Maintenance Planning

To perform the aircraft’s upgrades in most cost effective manner, with high quality and performance, following are some additional recommendations for proper utilization of system engineering approach:

3.1 Life Cycle Cost. The total life cycle cost (LCC) of a system is the sum of the costs arising from the system procurement (planning, developing, manufacturing, installing) plus those costs resulting from the system operation, maintenance, upgrading and the dismounting and disposal of the system at the end of the life time [4]. LCC is calculated during early planning, preliminary design and final design phases of a system. Knowing a system’s life cycle characteristics and future behavior in advance enables decision makers to assess the cost-effectiveness of utilization, logistic support and engineering improvements scenarios before they are implemented [5]. The LCC can only be slightly modified and influenced during the subsequent manufacturing / construction and the installation, commissioning and operation / maintenance phases. The LCC is drawn graphically as shown in Figure 2, for proper evaluation and approaches are adopted for minimizing LCC.

Recommendations and approaches for minimizing the LCC are [6]:

An understanding of customer affordability or competitive pricing requirements by the key participants in the development process;

Establishment and allocation of target costs down to a level of the hardware where costs can be effectively managed;

Commitment by development personnel to development budgets and target costs;

An understanding of the product's cost drivers and consideration of cost drivers in establishing product specifications and in focusing attention on cost reduction;

Active consideration of costs during development as an important design parameter appropriately weighted with other decision parameters;

Creative exploration of concept and design alternatives as a basis for developing lower cost design approaches;

Access to cost data to support this process and empower development team members;

Application of design for manufacturability principles as a key cost reduction tactic;

Figure 2: Stages of Life Cycles Costs

Use of value analysis / function analysis and its derivatives (e.g., function analysis system technique) to understand essential product functions and to identify functions with a high cost to function ratio for further cost reduction;

Meaningful cost accounting systems using cost techniques such as activity- based costing (ABC) to provide improved cost data;

Consistency of accounting methods between cost systems and product cost models as well as periodic validation of product cost models; and

Continuous improvement through value engineering to improve product value over the longer term.

3.2. Risk Assessment and Safety.

Risk management is a continuous commitment to the process of identifying, assessing, handling, and monitoring a set of risks. It is a sub process of system engineering [7].

The designer examines possible alternatives, and associated risks/problems are identified. Resolutions of the risks are evaluated and weighed in the consideration of project alternatives and cost models [8].

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4. PRACTICAL EXAMPLE

In developing countries perspective usually the airframe of aircraft last for 25-30 years. In this entire period the fast growing electronic development greatly affects the avionics and

weapons systems of aircrafts.

This results in the two or three upgrades of these systems in one airframe, with more quick and intelligent avionics and weapon systems as shown in Figure 3. System engineering approach before any upgrade program will not only save cost, but also improve the performance level of the overall system. The complete avionics system of an aircraft consists of many systems/sensors. The performance of different systems of aircraft avionics are interdependent and if proper system engineering approach is followed before the commencement of the upgrade the better utilization could be exploited.

If an Air Force of developing countries wants to upgrade the avionics system of its aircraft, the main problem is cost. The budget for any upgrade program is usually limited. Most Air Forces of the world adopts a phase wise approach for the upgrade programs. Here lies the key for the adaptation of system engineering approach.

Figure 3: Aircraft system

In phase wise upgrade programs, in-order to ensure the optimal utilization of integrated systems/sensors can only be possible if proper system engineering and task definition is done at the early stages of the upgrade program. This

approach seems to be a bit costly and difficult at the start but the tremendous amount of benefit could be foreseen at the completion of the upgrade program.

The System Engineering Approach guides each phase of the upgrade and also sets the hierarchy among different phases.

If in an upgrade program an Air Force foresee the integration of a new and technologically advanced airborne radar system, Inertial Navigation System (INS) and a newer generation weapon system. This is a typical upgrade program due to the fact that life of an airframe is more and typically it faces two to three advanced avionics/weapons systems.

The hierarchy of this upgrade program could be:

Integration of Radar in the first phase

Integration of INS in the second phase and

Integration of weapon in the third phase.

This scheme seems very appropriate as due to the integration of radar the great operational benefit could be foreseen easily in short time scale. An enhancement in capability in this approach is very small keeping in mind the overall upgrade program. As radar baseline is freezed according to the requirements of the aircraft prior to the first phase baseline. The radar inputs at this stage will reflect the requirements of an old low grade INS or DG/VG (directional gyro/vertical gyro) system. The INS is responsible for the own platform data. The design and output of the Radar is based on less accurate data and many assumptions and approximations are required to finalize the radar integration. In the second phase when old low-grade INS or DG/VG system is to be replaced by newer INS system, the benefits of newer INS system could not be utilized fully, as there is no co-ordination between the two phases. This also effects the third phase future weapon integration requirement, as important data required for the calculation of dynamic launch zone (DLZ) of weapon is missing due to the un-availability of own-ship platform data like own velocities and acceleration at the time of integration of radar. If this data is made available at the time of integration of radar, the radar output can be considerably improved and more accurate data is available like target velocity and acceleration.

Airframe

AV-I Avionic

System -II AV-III

WP-I Weapon

System -II WP-III

Time years 25-30

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If system engineering approach is followed at the start of the up-grade program and proper system studies were carried out before the commencement of project, the system can operate efficiently and optimally. In the above example, the platform sits with the better sensor/systems but the optimal utility of these sensors/systems could not be benefited due to the missing link of system engineering.

By adopting the system engineering approach one can address the issue either by setting of the precedence of the tasks or by putting the growth options in the first phase, which can be exploited later.

Star Analysis of above example is shown in the figure 4 (only some inputs and outputs are considered):

5. THE CHAIN STAR ANALYSIS

For selection of appropriate sequence of technology upgrade, the chain star analysis can be performed. Star of each option of upgrade become input or output for other star and connect each other for developing a chain for a particular system. The chain sequence with minimum number of dotted lines and maximum solid lines in chain can be achieved by performing different iterations of sequence of stars. The chain analysis is effective only in the case when the options are dependent or related with each other, but not in the case with independent options.

(Inputs) (Outputs) ADC New Weapon

System

New INS

New Weapon System

New INS

Mission Computer

Old INS

Figure 4: Star Analysis implementation

6. PRAGMATIC PRINCIPLE

Some of the key points [9] for successful implementation of System Engineering Approach are:

Know the problem, the customer, and the consumer

Use effectiveness criteria

Establish and manage requirements

Identify and assess alternatives

Verify and validate requirements and solution performance

Maintain integrity

Use articulated and documented process

Manage against a plan

Proper communication between all stakeholders.

7. CONCLUSIONS

System Engineering Approach has proved to be one of the most appropriate ways to deal with the aircraft up-gradation in developing countries. Systems engineering is a standardized, disciplined management process for development of system solutions especially of up-gradation projects that provides a cost effective approach to system development in an environment of change and uncertainty. It provides real-time product and process development and ensures that the accurate technical tasks get done during design and development through planning, tracking, monitoring, and coordination. Application of this technique, with tools like star analysis, life cycle costing, and risk assessment & safety can results in cost effective, high reliable and efficient system.

REFERENCES

[1] MIL-STD-499B Systems Engineering [Draft] 6 May 92.

[2] Fort Belvoir, System Engineering Fundamentals, Defense Acquisition. Virginia 22060-5565 University Press.

[3] Tran Thi Phien, “System analysis and design”. Institute of information technology NCST Vietnam.

Radar

Up-gradation

Velocity (own platform)

Mach No, Air

Density Ratio

Acceleration (own

platform)

Heading

Range, Target Position

Target

Acceleration

Target Velocity

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[4] Wolfgang Ansorge, “System engineering, design optimization, and safety conformity.”

[5] Sean Connors, Julie Gauldin, Marshall Smith, “closed-loop, simulation-based, systems engineering approach to life cycle management of defense system.” Proceedings of the 2002 Winter Simulation Conference.

[6] Kenneth crow, “Achieving target cost / design-to-cost objectives.” DRM Associates.

[7] David L. Lindblad. “System Engineering: A Risk Management Approach”. TRW Systems, ICBM Prime Integration Contract.

[8] Center for Technology in Government University at Albany / SUNY, “A Survey of System Development Process Models”. CTG.MFA – 003.

[9] Texas, Center for Professional Capacity Development. Transportation Institute.