|
Signature Measurements Standards Group Radar Committee REPORT ON STATUS OF RCS RANGE CERTIFICATION DEMONSTRATION (Updated 5 January 2000)
WHERE ARE WE TODAY? WHAT IS IN THE NEAR FUTURE? WHAT CAN NON-PARTICIPANTS DO NOW? WHAT ARE THE LONG-TERM PLANS? HOW, AND BY WHOM, WILL CERTIFICATION BE GRANTED? CAN OTHERS ACCESS RCSWEB? CAN WE GET A COPY? POINTS OF CONTACT
SUMMARY 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.
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? 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. WHAT IS IN THE NEAR FUTURE?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).
WHAT CAN NON-PARTICIPANTS DO NOW?
WHAT ARE THE LONG-TERM PLANS? 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. HOW, AND BY WHOM, WILL CERTIFICATION BE GRANTED?
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.
CAN OTHERS ACCESS RCSWEB? CAN WE GET A COPY? 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
TABLE OF CONTENTS FOR 'THE RANGE BOOK' (draft)
| ||||