[This article was first published in Army Sustainment Professional Bulletin, which was then called Army Logistician, volume 2, number 2 (March–April 1970), pages 4–8.]
IN AN AGE when weapon system requirements are so stringent and technology advances so rapidly, those in Army materiel development must use resources wisely to obtain the best possible weapon systems that will insure U.S. superiority in land combat. The current high potential for employing rapidly expanding technology requires intensive application of the most powerful, modern analytical tools available in the development of weapon systems within allocated resources. Systems analysis is one of these analytical tools.
Although the function of systems analysis at Department of Defense (DOD) and Department of the Army (DA) levels is relatively well established, there is a question about the proper role of systems analysis within commands of the U.S. Army Materiel Command (USAMC). This article presents systems analysis as it is employed in the U.S. Army Weapons Command (USAWECOM).
The role of systems analysis in the USAWECOM differs from that in higher echelons because of mission differences. To put the mission of the USAWECOM in proper perspective, consider the organization and mission of the various defense agencies. For example, the U.S. Army Combat Developments Command (USACDC) has the mission of developing combat strategies and determining materiel requirements for implementing that strategy within the Army. The USAMC is then responsible for developing materiel which the USACDC has identified to support its strategy.
Within USAMC there are several commodity commands, each developing particular kinds of products. The USAWECOM has responsibility for developing the Army's conventional weapons. Small arms, aircraft armament, artillery, air defense weapons, and tank systems are some examples.
Systems analysis at the various echelons performs various tasks. As defined by Quade and Boucher in Systems Analysis and Policy Planning, systems analysis is "a systematic approach to helping a decision-maker choose a course of action by investigating his full problem, searching out objectives and alternatives, and comparing them in the light of their consequences, using an appropriate framework—insofar as possible analytic—to bring expert judgment and intuition to bear on the problem." This definition is quite general and could apply to a university, an economic system, the DOD, or one's own personal financial planning.
There are several key features of the definition, however, which differ in meaning depending upon the application made of the systems analysis technique. Here are some of those features:
• SYSTEMATIC APPROACH. The approach taken to solve any system development problem will be dictated by the problem and the environment in which the analyst finds himself. There is no precise, standard set of tools that the systems analyst uses routinely.
• DECISION-MAKER. Before beginning a study, the analyst must understand clearly who the decision-maker is, the kind of decision that is to be made, and the level of analysis that must be made in order to support a reasonable decision.
• FULL PROBLEM. A vital part of the problem-solving process includes defining the objectives and alternatives available to the decision-maker.
• COMPARISON. Comparison of alternative systems must be consistent with the objectives of the sponsor and with his level of authority. It is important that the analyst not attempt to make decisions which are the responsibility of higher echelons of command. However, he should include the possible decisions made by higher echelons as inputs into his analysis.
• ANALYTIC. One feature common to virtually all systems analysis is a mathematical representation of the "real-world," rather than experimentation in the "real-world."
In order to illustrate the role of systems analysis at the USAWECOM, its functions at the various levels within DOD should first be reviewed.
The basic difference between the systems analysis performed at the different echelons is in the nature of the decision to be made or in the kind of comparisons which must be made in order that decisions may be reached. At DOD level, for example, comparisons might be made between mixes of Army, Navy, and Air Force elements to perform a particular mission.
At Department of the Army, on the other hand, organization or materiel resources within the Army are considered. A detailed analysis of individual weapon systems is generally not included. In the USACDC, comparison is made between different tactical doctrines and weapon classes. Within the USAMC, the decision to be made is which class of materiel item should be used to meet the particular objective which the USACDC has identified.
For example, at USAMC level, a comparison might be made between missiles and conventional gun systems to accomplish an objective.
In the USAWECOM, comparisons must be made between different weapons within the same generic class. In order to make a decision between different weapon systems, a detailed analysis of each weapon system with its technical characteristics must be performed. At USAWECOM level, then, distinguishing features of weapon systems must involve behavior and performance characteristics.
Five Functions Described
In order to assist the commanding general of the USAWECOM in his decision-making process, systems analysis must include five functions:
• Systems analysts must perform a requirements analysis to translate USACDC-identified objectives into weapon system technical requirements. The technical requirements, if met by design personnel, will result in a system which meets the objectives.
• In addition to simply meeting objectives, system studies must insure that the technical requirements are consistent with a balanced system. Recalling the adage that a chain is only as strong as its weakest link, it must be assured that no single feature is considerably weaker or stronger than any other.
• Systems analysis must compare weapon system alternatives based on technical performance, reliability, maintainability, and simplicity.
• Systems analysis must provide detailed "tradeoff" information relating weapon system features to weapon output. This information is used in realistic USAMC-USACDC cost effectiveness analyses. It is extremely important that analysis performed at the USAWECOM level include all the pertinent technical features of the weapon systems so that the potential value and the limitations of these various features can be realistically portrayed in USACDC operation modeling efforts. This realistic portrayal is required if the USAMC-USACDC iterative weapon system development concept is to be a success.
• Systems analysis should furnish tools developed in the systems analysis phase to engineers for computer-aided design of the weapon systems. A peculiar feature of systems analysis at USAWECOM level is that the analysis tools used in the study of weapon systems must be of sufficient depth that they can be of considerable aid to the weapon systems designer in engineering development.
Major Importance in Concept Formulation
Even though systems analysis is involved throughout the life cycle of materiel, it is felt that the concept formulation phase of the life cycle is the time when systems analysis techniques can have their greatest impact on the quality of weapon systems. With the current resource limitations for development of new weapon systems and the boom in technology, it is imperative that the best possible system be developed and tested before fielding. A concerted systems analysis effort early in the development process can reduce the number of system problems which can arise during final tests and even in early field use by troops.
Helicopter Analysis
To illustrate the kind of systems analysis problem which can arise in weapon system development, consider the relatively new field of helicopter armament. The Army has been mounting weapons on helicopters for only the past six to eight years. Because of high priorities and time limitations, existing weapons originally were attached directly to the helicopter frame. More recently a mount has been put on the helicopter which allows the pilot to aim a gun when it is attached to the mount. Even though extensive use has been made of guns mounted in this manner, indications are that considerable increases in effectiveness may be achieved by treating the aircraft with its weapons as an integrated armament system.
The first consideration in developing a weapon system is the mission of that system. Helicopter armament systems may be used in one of two basic roles on the battlefield. The first role is for suppression—to prevent the enemy from placing effective fire on the aircraft. If the aircraft sustains minimum damage, this is a measure of the armament system's effectiveness. This kind of armament system is typically used against targets which the pilot does not see. He only knows that they exist in an area. For this reason, a weapon with some dispersion is desirable. Early methods of mounting weapons on helicopters gave this dispersion because of vibration of the helicopter. These weapons have been quite effective in providing suppressive fire.
A second role of the helicopter is that of defeating a point target on the ground. A point target is an object of finite but small size, such as an armored personnel carrier, a bunker, or perhaps a truck. The objective of the armament system in this case is to defeat a target which can be seen clearly by the gunner. Further, this objective must be met by expending a minimum amount of ammunition because of weight limitations in the amount that can be carried by helicopters. The helicopter vibrations, in this role, now become limiting factors in the gunner's ability to direct the weapon on a point target. The problem, therefore, becomes one of developing a weapon and a weapon control device to stabilize the platform on which the weapon is mounted. To complicate the problem, the weight of control equipment reduces the amount of ammunition available for a mission.
The problem of accurately directing fire toward a point target can be further broken down into elements of developing system components to meet a total system objective of defeating point targets. Within the aircraft armament system there are numerous sources of error.
One obvious source is the gunner's inability to aim perfectly, hence, an inherent error due to the human operator. Another major source of error is the inability to compute aim direction as a function of helicopter velocity, altitude, and range. This error is called fire control error. In addition to the inability of the gunner to aim perfectly and the controlling system to direct perfectly, there are inherent errors in the ballistics or the round. This factor is beyond the control of the weapon designer.
Another major source of error is structural vibration of the helicopter. The helicopter is constructed of very flexible elements to satisfy the lightweight requirement. The entire helicopter structure is therefore flexible. When a weapon is fired, the angular oscillations at the weapon mount can be quite large. This is a source of error which must be considered. These are just a few of the error sources encountered when one attempts to hit a point target from a moving aircraft.
A major function of systems analysis in the point-fire role is the characterization of the possible error sources in the weapon system and to develop mathematical relationships which will relate the total system error to the component errors. Once this relationship is developed, sensitivity analyses may be performed to point out which of the error sources are most critical to overall system effectiveness.
Further, the distribution of error among the various components (error budget) can be allocated in an optimum way. In this problem, optimum may be defined as "maximum probability of hit, subject to constraints on system cost and weight." System optimization problems of this kind have received much attention in recent control literature, and methods are becoming available for their solution. This is just one case where newly developed system optimization techniques can be of significant value to weapon system analysts.
Problems of Systems Analyses
Aircraft armament is only one problem faced in systems analysis studies of Army weapon systems. There are several features of this problem worth noting. One man cannot possibly keep track of the technology involved in an analysis of this magnitude. An interdisciplinary approach to the problem must be taken. Some of the disciplines involved are:
• Structural analysis
• Control system theory
• Physiology
• Operations analysis
• System optimization
The success of a development project of this kind depends very strongly on the ability of a group having extensive knowledge in each of these functional areas to work together as a team, each identifying critical problem areas and lending his knowledge of the subject to the solution of the problem.
Each of the weapon system classes developed by USAWECOM presents a similar systems analysis problem. While emphasis in tanks, artillery, air defense, and small arms differs from that outlined in aircraft armament, the common feature in each is the technical level of expertise needed to solve the systems analysis problem. We can highlight the technical problems associated with each weapon class.
The problem of tank system development in many ways parallels that of aircraft armament for defeat of point targets. Although the constraints of the problem of weight, mobility, and other factors are quite different, the weapon control problems are similar. Briefly, both problems consist of integrating subsystems in order to maximize point target defeating capability.
In contrast to the very complex and sophisticated weapon control problems arising in aircraft, USAWECOM has responsibility for developing artillery systems where simplicity and ruggedness is desirable. The artillery piece is not nearly so complex as other weapon systems, and there are personnel within USAWECOM who have many years of experience in artillery design and analysis. This would seem to make the systems analysis job quite easy or even unnecessary.
As witnessed by the current activity in USACDC, however, the systems analysis job in artillery is incomplete. At present, there are a number of measures of effectiveness and constraints which the user has endorsed, such as low weight, long range, high mobility, armored, and low silhouette. Some of these goals conflict with each other, however, and it is not yet clear just which goals should be emphasized. Studies to determine desirable artillery features of air defense gun systems are proceeding at U.S. Army Weapons Command, U.S. Army Materiel Systems Analysis Agency, and U.S. Army Combat Developments Command.
A weapon system of critical importance today is gun systems for air defense. Little work has been done in air defense gun system development because of the emphasis on missile systems for air defense over the past 15 years. It now appears that an effective Army air defense system must involve a mix of both missiles and guns.
The relative lack of prior work in air defense gun systems presents a complex systems analysis problem at USAWECOM. Weapons performance analysis as well as operational analysis tools had to be developed for evaluating the many system and subsystem options. Some of the broad parameter variations which must be investigated are large versus small caliber guns, low versus high rate of fire, sophisticated and costly versus simple and inexpensive fire control, and self-propelled versus towed weapon.
Operational analysis tools are partially available for use in answering these questions, but a considerable amount of system engineering effort is needed to generate feasible weapon classes and provide inputs into operational models for evaluation.
Small Arms
The small arms weapon development problems faced by USAWECOM are quite different from each of the preceding problem areas. In the case of small caliber, man-carried and man-operated weapons, the interaction of man and weapon is a critical factor in the effectiveness of the weapon system. This major factor must be carefully accounted for in developing new weapon systems.
A further complication in the detailed operational analysis of a man-operated weapon is the wide range of environments in which the weapon may be used. The problem of relating design features of rifles and machineguns to their operational effectiveness is a complex problem now receiving considerable emphasis in USACDC. In this area, much as in artillery, the present USAWECOM systems analysis effort is concentrated on parametric tradeoff analyses of weapon input-output relations which are needed in USACDC operational studies.
These represent the wide range of technical and operational problems confronted by USAWECOM. Further, at USAWECOM most decisions which must be made in the development process involve subsystem options, the choice of overall system concepts, and questions of integration of the total weapon system. In order to help the commander make decisions on these matters, systems analyses at USAWECOM must involve in-depth technical analysis of weapon system performance.
In line with General Westmoreland’s principles of reliability, maintainability, and simplicity, it is paradoxical that deep, technical systems analysis is required. The only means of insuring these qualities, however, is detailed analysis to obtain maximum effectiveness from a particular design concept rather than adding gadgets to an inferior basic design. The key is an intensive application of analysis and technology rather than an extensive application of manpower and gadgetry.
The kind of systems analysis outlined above is believed to be essential at the USAWECOM. It is only through such an intensive application of analysis and technology that quantum improvements in Army weapons systems can be achieved while reducing system life cycle costs.
Major General Henry A. Rasmussen is commanding general of the U.S. Army Weapons Command at Rock Island Arsenal, Illinois. A former assistant to the Deputy Chief of Staff for Logistics, Department of the Army, General Rasmussen served as ACofS, Logistics, J-4, U.S. Military Assistance Command, Vietnam, before assuming his current command.
| Date Taken: | 12.11.2024 |
| Date Posted: | 12.11.2024 09:48 |
| Story ID: | 487183 |
| Location: | US |
| Web Views: | 17 |
| Downloads: | 0 |
This work, Systems Analysis in the U.S. Army Weapons Command by MG Henry A. Rasmussen, must comply with the restrictions shown on https://www.dvidshub.net/about/copyright.
