Range Commanders Council
Signature Measurements Standards Group
Radar Committee
(Updated 5 January 2000)

This history file originally published 8 January 1998 and most recently updated 5 January 2000.

In the Spring of 1996, the SMSG Radar Committee (also known as the Radar Cross Section Measurements Working Group) proposed to investigate what it would take to certify RCS ranges. The basic premise behind the certification concept is that the overall quality of data gathered at the various RCS ranges varies considerably, and there is room for improvement. At that time, the members of the Radar Committee were involved in a project working with the National Institute of Science and Technology (NIST) to quantify error budgets. An outcome of that effort was the collective realization that 'we' were not collecting data quite at the quality level we thought we were. That realization resulted in some rather critical self examinations and a further realization, collectively, that we can do better.

The task has been formally assigned to the Radar Committee of the Signature measurements Standards Group (SMSG) of the Range Commanders Council (RCC).

Early efforts included the investigation of existing standards to try to establish a baseline or frame of reference. We found that in 1994 the National Conference of Standards Laboratories (NCSL) published a document (with the American National Standards Institute (ANSI)) designated as ANSI/NCSL Standard Z-540-1994-1 as the U. S. equivalent of the International Standards Organization document ISO-25. It is a brief 13 page overview establishing the minimum competence to which any calibration laboratory must adhere to produce calibrated data (temperature, pressure, lumens, weight, etc.) for any item being supplied to it. In essence, producing RCS measurements is akin to calibrating a target to yield its respective RCS data as compared to a standard. In the case of RCS, that standard and the processes used to measure and collect data vary from range-to-range. The proposed certification process will primarily standardize the documentation of day-to-day range operations, the calibration techniques that are known to give superior (more accurate) calibration results and some of the data analysis associated with these techniques. The primary objective is to produce better RCS measurements, analysis and data products. [NOTE: ANSI/NCSL Z-540-1-1994 can be purchased for $16/copy by calling (303) 440-3339.]

In the spirit of inter-service and industrial cooperation, a major RCS Range Certification conference was hosted by NIST at Boulder, CO 4-6 March 97 to discuss what, by then, became referred to as the "certification demonstration project." The meeting was open to all RCS professionals employed by U. S. companies or U.S. government agencies. The purpose of the demonstration project is to certify that ranges meet documentation and technical standards accepted by the RCS community. The concept is simple: well documented ranges permit traceability of the data products, while, at the same time can readily improve their RCS measurements, when needed. Internally, range operators gain a much better understanding of how well they do business (years of static assumptions are reexamined, and where appropriate, thrown out and replaced by documented practices and evidence). The overall effort was briefed and many speakers took the podium to address what they were doing with regards to such an effort. As it turns out, a number of entities, both government and industrial, were already working on similar projects.

Some concerns emerged at the meeting; these were issues about costs, openness of communication, and trade secrets. By the end of the third day, it was apparent there was considerable interest in the concept.

Since March 1997, there have been concerns expressed within the RCS community, particularly with regard to what might be going on behind the scenes. This newsletter is part of a conscious effort to keep interested parties abreast of the developments in the National RCS Certification Project, and, in particular, the DoD demonstration project.

At this point, the active government participants in the feasibility demonstration program are the Air Force Research Laboratory (Code XR at Wright-Patterson AFB), the Naval Air Warfare Center Aircraft Division (NAWC-AD) at Patuxent River, the 49th Test Group at Holloman AFB (RAMS, in part), and recently on a limited basis, the millimeter range at Eglin AFB. In addition, Boeing has committed considerable resources to certify all their RCS measurement ranges.

Why those five? Diversity. Each range represents a very different kind of operation, and the purpose of any feasibility demonstration is to explore how well a concept works. In the RCS community, the range certification concept must be applicable to all ranges in order to achieve the fundamental goal of the program: improve the overall quality of RCS measurements and data products.

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This history file originally published 8 January 1998 and most recently updated 5 January 2000. Updated information is italicized.
The focus over the last two years has been on what has become known as The Range Book outlined in The Handbook for the Assurance of Radar Cross Section Measurements [view on-line or download (MS Wordv6)]. The Range Book is essentially the implementation of the standards stated in some detail in the Handbook, specifically tailored to meet the needs of each range. NIST, in conjunction with the participating ranges, has been examining the ANSI-Z-540-1 standard and tailoring it to the needs of the RCS community. Progress towards creating range books at the various participating ranges (Air Force Research Lab, Naval Air Warfare Center Aircraft Division, and National Radar Test Facility (aka: RATSCAT/RAMS)). In October 1999, two Range Book Evaluation Panels took up the task of reviewing the Range Books from AFRL and NAWCAD. The review panels are winding up their reviews this month. They will soon turn over their findings to the respective facilities so the ranges may begin to effect corrections/modifications/ updates. The 4th Annual Certification meeting, co-hosted by NIST and AFRL at Boulder, CO has been postponed from March 2000 until June 2000 to ensure the reviews are complete and the value of the Lessons Learned is maximized.

When creating a Range Book the following should be kept in mind: ANSI-Z-540 requires that processes be documented, test procedures be written, calibration traceability be established, report writing and documentation be made uniform (with content individualized by each range). Good "common sense" approaches applied to documenting range performance are encouraged.

The Table of Contents (as it exists today) for the Range Book is provided at the end of this report.

The participants are moving along a path toward completing the documentation of their respective ranges. They are not moving at the same pace, nor necessarily in the same manner.

What form should The Range Book take?
At NAWC-AD, an early decision was made to create electronic documentation to take advantage of existing technology and capitalize on existing resources as much as possible. The concept has been presented to other participants and has been well received. Known as the RCSweb, it lends itself very well to organizing a wide range of information in a dynamic environment. It uses the now very familiar Internet/Intranet technology, and it permits the exercise discretion and creativity. It does not restrict the user to a particular format nor hardware/software suite.

However, the electronic approach is not required; ranges may use three-ring binders, or a dedicated filing system. The implementation method is entirely up to the respective ranges. (Evaluators much prefer printed versions, though they m ay be printed versions of the web-based Range Book--keep this in mind when designing web-based systems.)

As for resources, both the USAF and the Navy have each committed on the order of $500,000 to this effort, essentially 'out-of-hide.' A key component of the effort is corporate commitment, both in terms of funding and personnel. Critically, it is essential to recognize, at the outset, that implementation of a range standards program will demand time, dedication and perseverance.

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Participating ranges are continuing to document the details of their respective operations. NRTF/RATSCAT/RAMS and Boeing continue to work on their Range Books, with Boeing setting aside a substantial amount of funds for the project. NIST remains interested in comments and suggestions for the proposed Handbook and planning for the second annual RCS Certification Conference (see next paragraph). In October 1997, some 100 copies of the draft Handbook were distributed at the Antenna Measurements Techniques Association (AMTA) meeting in Boston. Though the deadline for comments was to be mid-November 1997 for the March 1998 release of the Handbook, any later comments will be incorporated in future releases (contact Dr. Lorant Muth, NIST, see below).

The third annual RCS Certification Conference, cosponsored by NIST and the AFRL, WPAFB, was held March 3-4, 1998 in Boulder, CO. The agenda included sessions on Calibrations and Interlaboratory Comparisons, RCS Standards, RCS Uncertainty Analysis, and the DoD Demonstration Project. Participation included U.S. nationals in the RCS community, as well as Canada, The United Kingdom, and Australia. encouraged. Contact Dr. Lorant Muth at NIST (see below).

If you have concerns, ideas or suggestions, direct them to one of the participants (contact information below).  Plan to participate in the fourth RCS Range Certification conference at NIST in June, 2000.

The timeline for the feasibility demonstration runs through June, 2000. At the third Annual RCS Certification Conference, the participants will brief all interested parties on the experiences, lessons learned, products, and processes which have been (or will be) incorporated to achieve the requirements of the certification process.

The certification process will be an ongoing effort. The first phase will probably take on the order of five years. Ranges wanting to undergo certification will be able to obtain all necessary information from NIST, or other certified ranges.  Everything is being done to assure that the process is multilateral and cooperative. All information on certification requirements will be readily available to any U.S. company in the form of publications, reports, contact information and the like.

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Evaluator Qualifications
Range Book Evaluation Criteria
The details of the certification process have been developed and have been tested in the Demonstration Project as well as at multiple industry facilities. Qualification thresholds have been established for evaluators, along with Evaluation Criteria for the Range Books. Evaluators are solicited from all interested facilities engaged in RCS measurements, including DoD, industry and academia. Additionally, NIST provides representation to the panels. Each panel is comprised of three members (including NIST). The process of soliciting and selecting evaluators is administered by an independent facilitator.

A Range approaching the completion of its Range Book (within 30 days of completion), should contact the National RCS Measurement Facilities Certification Program Facilitator (, (301) 904-4627) to request a panel be formed. Candidates will be solicited from the pool of vetted reviewers. Those reviewers available to participate will so advise the SMSG Secretary. Contact and affiliation will be provided to the Requesting Range, which will have the opportunity to veto any proposed Review Panel Members (for any reason). If any proposed panel members are vetoed, the SMSG Secretary will advise the affected proposed panel member. The Secretary will send out a request for a substitute until a suitable panel of three vetted reviewers is enpaneled.

The RCSweb is a developmental effort at NAWC-AD and includes information that is strictly For Official Use Only and relevant only to operations at NAWC-AD. Aside from that, it is hosted on a system behind a firewall and access is restricted to a very limited number of people engaged in the development of RCSweb and those with a need to access the information contained therein. An effort is underway to develop a template, a series of templates, and/or a wizard to assist others in the creation of a similar site using Web-based tools. Demonstrations can be arranged. [NOTE: This Web site is provided in lieu of a planned CD-ROM.]

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For further information, or to voice concerns, ideas, suggestions or interest in the program, please contact the following:

, Facilitator, National RCS Measurement Facilities Certification Program, (301) 904-4627


1. Introduction
2. Applicable Documents
3. General and Specific Technical Definition Glossary
4. Organization and Management Structure
5. Quality System, Audit Trail, and Review
6. Personnel Information
7. Range Accommodation and Environment
8. Equipment, Reference Material and Configuration Control
9. Measurement Traceability and Calibration
10. Measurement and Calibration Procedures
11. Range Handling Procedures for RCS Standard Calibration Items
12. Record Keeping System
13. Certificates and Reports
14. Subcontracting Records (Calibration-related)
15. Outside Services and Supplier Records (Calibration-related)
16. Complaint Response System
17. Inter-laboratory Comparison Programs
18. Data Processing Procedures
19. Range-Specific Uncertainty Analyses
20. On-going Research and Planned Improvements
A - Measurement Assurance Plan (MAP)
B - Security and Classification Matters
C - Safety
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