This chapter provides the study context and task statement. It also describes the purpose and scope of the study and how the report is organized.
The National Research Council (NRC) consists of several boards and their associated committees that bring the complexities of protection materials science research and applications into focus for Department of Defense (DoD) sponsors. These include the Board on Army Science and Technology, the National Materials Advisory Board, and the Army Research Laboratory Technical Assessment Board of the NRC’s Division on Engineering and Physical Sciences and the Committee on National Statistics of the NRC’s Division on Behavior and Social Sciences and Education.
In 2009, the Government Accountability Office (GAO) released a report that commented on the conduct of the test procedures governing acceptance of body armor vest-plate inserts worn by military service members (GAO, 2009). The GAO report, as well as other observations (for example, the Army Audit Agency report to the Program Executive Officer Soldier on Body Armor Testing (AAA, 2009), led the DoD Office of the Director, Operational Test and Evaluation (DOT&E) to request that the Division on Engineering and Physical Sciences conduct an ad hoc study to investigate issues related to the testing of body armor materials for use by the U.S. Army and other military departments.
Box 1-1 contains the statement of task for the three-phase study. Phases I and II were completed in 2009 and 2010 respectively and resulted in two NRC letter reports (NRC, 2009 and 2010).4 This report is the Phase III report. To ensure wide dissemination, no classified or restricted information is contained in the reports. The sponsor also specifically requested that the NRC report emphasize the science rather than the policy aspects of the body armor testing issues.
4Findings and recommendations from the Phase I and Phase II reports are in Appendixes K and L respectively.
The National Research Council will convene specialists in committee form to consider the technical issues relating to the testing of body armor. To do this the National Research Council shall conduct a 3-phase study:
In Phase I a committee will comment on the validity of using laser-profilometry/ laser-interferometry techniques to determine the contours of an indent made by a ballistic test in a non-transparent clay material at the level of precision established in the Army’s procedures for testing personal body armor. If laser-profilometry / laser-interferometry is not a valid method, the committee will consider whether a digital caliper can be used instead to collect valid data. The Committee will also provide interim observations regarding the column drop performance test described by the Army for assessing the part to part consistency of a clay body used in testing body armor. The committee will prepare a letter report documenting the findings from its Phase I considerations. This is a six week effort beginning November 1 2009 and ending mid December 2009.
In Phase II a committee will consider in greater detail the validity of using the column drop performance test described by the Army for assessing the part-to-part consistency of a clay body within the level of precision that is identified by the Army test procedures. The committee will prepare a letter report documenting the findings from its Phase II considerations. This is a three months effort beginning November 1 2009 and ending early February 2010.
In Phase III a committee will consider test materials, protocols and standards that should be used for future testing of personal armor by the Army. The committee will also consider any other issues associated with body armor testing that the committee considers relevant, including issues raised in the Government Accountability Office Report—-Warfighter Support, Independent Expert Assessment of Body Armor Test Results and Procedures Needed Before Fielding (GAO-10-119). The committee will prepare a final report. This is a 14-months effort beginning November 1 2009 and ending January 2011.
The final report will document the committee’s findings pertaining to the following issues that are of particular immediate concern to DOT&E including the following:
•The best methods for obtaining consistency of the clay, and of conditioning and calibrating the clay backing used currently to test armor.
•The best instrumentation (e.g., laser scanning system, digital caliper, etc.) and procedures to use to measure the back face deformation (BFD) in the clay.
•The appropriate use of statistical techniques (e.g., rounding numbers, choosing sample sizes, or test designs) in gathering the data.
•The appropriate criteria to apply to determine whether body armor plates can provide needed protection to soldiers; this includes the proper prescription for determining whether a test results in a partial or complete penetration of body armor, including, as appropriate, the soft armor underlying hard armor.
The final report will also document the committee’s findings regarding any other issues regarding body armor testing that the committee found relevant. The study team will have access to all data with respect to body armor testing that the team needs for the conduct of the study.
The last task for Phase III of the study was to document in its final report any other issues regarding body armor testing that the committee found relevant. In response, this Phase III report also attempts to do the following:
- Provide a roadmap to reduce the variability of clay processes and show how to migrate from clay to future solutions.
- Consider the use of statistics to permit a more scientific determination of sample sizes to be used in body armor testing.
- Develop ideas for revising or replacing the Prather study methodology;
- Review and comment on methodologies and technical approaches to military helmet testing.
- Consider the possibility of combining various national body armor testing standards.
Appendix C contains the specific tasks that were identified for the Phase III portion of the study. A matrix relating the statement of task to specific sections of the report is included as Appendix D.
From the outset, the committee recognized that the body armor testing community exists in a charged environment where the lives of service members and law enforcers are at risk. Efforts to improve body armor testing processes should lead to the fielding of more effective body armor and helmets for our servicemen and women. To be most effective, body armor and helmets should be in the “sweet spot” where there is a balance between survivability and light weight. The broad purposes of the study were to verify and validate current test procedures for body armor plates, to investigate longstanding issues related to the testing processes, and to recommend approaches that will improve future testing methodologies and procedures.
As directed by the task statement, the study was divided into three phases.
- The Phase I letter report focused on the validity of using laser-based measuring techniques to determine the contours of an indent made in a nontransparent clay material by a ballistic test. The report offered interim observations on the column drop performance calibration technique being used by the Army’s Aberdeen Test Center for assessing the part-to-part consistency of a clay body used in testing body armor. It also provided immediate feedback on issues raised by the GAO report (GAO, 2009). The specific findings contained in the Phase I letter report are listed in Appendix K.
- The Phase II letter report focused on the use of clay as a backing material during body armor testing. It examined in detail the validity of using the column drop performance calibration and recommended alternatives for future backing materials. Additionally, the report discussed use of statistically based protocols in body armor testing and described an approach to developing a single national body armor testing standard. The recommendations of the Phase II committee are contained in Appendix L.
- In this final report, the Phase III committee has carried out the Phase III tasks and consolidated and expanded on information contained in the two earlier letter reports. This final report provides a road map to reduce the variability of clay processes and eventually migrate from methods based on clay to other methodologies. It also develops ideas for revising the medical basis for testing procedures and addresses technical approaches to military helmet testing.
To complete the study, the Phase III committee conducted data-gathering sessions at the U.S. Army Aberdeen Test Center in Maryland and at the National Academy of Sciences Keck Center in Washington, D.C. The chair assigned committee members to working groups in the following task areas: clay and instrumentation; body armor testing methodologies; statistics; and helmet testing. To facilitate the study, the separate working groups conducted individual data-gathering sessions, teleconferences, and, in two instances, site visits. The leaders of the working groups coordinated the gathering of data and consolidated written inputs into chapters for the overall report. Appendix B provides a list of the committee briefings and activities.
Chapter 3 (Historical Basis for Current Body Armor Testing) reviews the foundational basis for the testing methodology that has been used since the late 1970s. Chapter 4 (Clay and Backing Materials) assesses the use of clay in testing and describes how the variability inherent in the backing material may be incorrectly attributed to variability in the armor. Chapter 5 (Instrumentation and Procedures for Measuring an Indent in the Backing Material) offers insights into measuring devices.
Chapter 6 (Statistical Considerations in Body Armor Testing) discusses findings on the statistical aspects of body armor testing with a focus on body armor plate testing, and Chapter 7 (Helmet Testing) extends the discussion of testing to the testing of combat helmets and provides ideas for future improvement.
Chapter 8 (A Medical Basis for Future Body Armor Testing) describes the current lack of a medical basis for body armor testing and recommends a direction
for future medical research and analyses. Finally, Chapter 9 (Future Improvements in Testing Methodology) looks to the future of body armor testing and describes what is needed to improve or replace the methodology that has for decades underpinned body armor testing.
The report includes several appendixes as described in the chapters and listed in the contents.
AAA (U.S. Army Audit Agency). 2009. Body Armor Testing. A-2009-0086-ALA. Alexandria, Va.: U.S. Army Audit Agency.
GAO (Government Accountability Office). 2009. Warfighter Support: Independent expert assessment of army body armor test results and procedures needed before fielding. GAO-10-119. Washington, D.C.: Government Accountability Office.
NRC. (National Research Council). 2009. Phase I Report on Review of the Testing of Body Armor Materials for Use by the U.S. Army: Letter Report. Washington, D.C.: National Academies Press.
NRC. 2010. Phase II Report on Review of the Testing of Body Armor Materials for Use by the U.S. Army. Washington, D.C.: National Academies Press.