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This paper presents the approach and results for the Aeronautics Test Program (ATP) FY11 Facility Assessment Project. ATP commissioned assessments in FY07 and FY11 to aid in the understanding of the current condition and reliability of its facilities and their ability to meet current and future (five year horizon) test requirements. The principle output of the assessment was a database of facility unique, prioritized investments projects with budgetary cost estimates. This database was also used to identify trends for the condition of facility systems.

Increasing need to reduce the cost of space programs has resulted in higher scrutiny of test program requirements. Tailoring of test parameters to lower test stress levels is commonly proposed as a method to shorten program schedules. Test tailoring at the spacecraft unit level frequently focuses on the number of cycles in thermal cycle and thermal vacuum testing because test cycles greatly impact test cost. A consequence of reducing the number of cycles in unit-level thermal testing is an increased likelihood that latent defects will escape detection and pass into assembly and integration, where reduced-stress test environments decrease the chance of forcing latent defects into failures. In a worst-case situation, these escapes will not be found in vehicle-level testing but will become flight anomalies. Furthermore, test failures found at higher levels of assembly are significantly more expensive to repair due to vehicle access difficulty and program schedule pressures. As a result, cost savings realized in unit-level test reductions may be offset by considerably higher costs of repairing unit-level test defect escapes as they are found in subsystem or vehicle-level testing. Despite these risks, many current space programs require tailoring of test requirements to meet schedule and cost constraints. Therefore, an assessment is made of unit features or opportunities that could reduce testing requirements while ensuring low risk of jeopardizing mission objectives. Design history, additional testing activities, and program risks are considered for potential test program improvements. Criteria are presented whereby a unit may successfully meet test objectives even with reduced test parameters.

The ESA European Space Agency is currently developing the project EXPERT – Experimental Re-entry Vehicle Test-bed. The EXPERT capsule features a generic simple shape and will perform a sub-orbital ballistic hypersonic flight; with a selection of major shape parameters to avoid any surface active oxidation, degradation and flow contamination. The main objective of the EXPERT mission is to collect in-flight data on the most critical ATD phenomena via dedicated classical and advanced flight test measurement assemblies ( i.e . EXPERT Scientific Payloads); the scientific data will then to be used to validate state-of-the-art numerical tools for aerothermodynamic applications and ground-toflight extrapolation procedures. In order to efficiently manage the very high numbers and typology of testing activities, the qualification activities have been guided in a frame of payloads coordination among all partners and test facilities for a proper harmonization and optimization of all test requirements and results. In the present paper we present an overview of all on-ground activities aimed to qualify and verify the designed and manufactured payloads actually ready for the flight

In this work a unique test conducted in an arc-heated facility to determine the suitability of an iridium (Ir) alloy for high-temperature, high-pressure nozzle applications is described. These tests were conducted in the High-Enthalpy Ablation Testing (HEAT) H1 facility, located at Arnold Engineering Development Center (AEDC). This is an arc-heated facility typically used for reentry vehicle materials testing. The requirements of this test necessitated a unique holder design and careful placement of instrumentation to verify that test requirements were met. During the test, holder ablation was more rapid than expected; nevertheless, the goals of the project were achieved, with the Ir alloy showing impressive performance, even when a sharp leading edge was exposed directly to the hot flow. This paper describes the details of the test design process, including various trade-offs made, the experimental setup, the test itself, and results from posttest analysis.

The KC-X program is replacing the aging KC-135 air refueling tanker aircraft fleet. For the past few years, the acquisition strategy called for a commercial derivative aircraft as the basic airframe. Using a commercial derivative aircraft in a military application challenges test and evaluation organizations. Myriad commercial data constraints coupled with multiple civil and military test requirements complicates efficient and effective planning. Developing a test concept for the KC-X requires interaction between contractors, acquisition officials, system users, USAF test agencies, and the Federal Aviation Administration. The Integrated Test emphasis within the Department of Defense (DoD) arrived at the correct time to make a positive impact on the KC-X test program. All stakeholders in the program have a vested interest in making the test and evaluation program as efficient as possible and senior DoD leadership is interested in ensuring the success of the integrated test concept. The paper reviews the DoD integrated test concept, identifies characteristics of operational test events required by public law and policy, and discusses integrated test methods, which comply with public law and DoD policy. Implementation challenges are also discussed to include KC-X test community methods addressing integrated testing challenges, tracking of test events, and identifying integrated test opportunities.

Testing in high-enthalpy ground test facilities typically requires investigators to measure flow parameters by utilizing intrusive probes. Measurements include species concentration, Mach number, flow angle, total pressure, and total temperature. The probes must be cooled to withstand the high-enthalpy environments. New test articles and facility improvements continue to introduce harsher test conditions, and innovative fabrication methods and enhanced cooling schemes have improved survivability in these high-enthalpy environments. In intrusive testing, it is also desirable to minimize the size of the probes to reduce the impact on both the test stream and the test article. The Arnold Engineering Development Center (AEDC) is also developing a suite of miniaturized probes (diameter less than 0.1 in.) to address the measurement requirements of propulsion systems’ internal flows. This paper describes ongoing and planned AEDC probe activities, including several test applications, general design and cooling schemes, and probe designs to meet future test requirements.

Up to now altitude tests on upper stage engines and satellite systems are indispensable. The need to develop, qualify and accept propulsion systems under actual operating conditions with fully expanded nozzle defines the essential criteria for the test requirements. For the ARIANE 5 launcher evolution the new VINCI upper stage engine will be developed and tested under vacuum conditions. The existing altitude test Bench P4 at the DLR test centre Lampoldshausen will be adapted to the new test conditions. The modifictions, specially the new altitude simulation are designed and the work is nearly finished. VINCI is an Expander cycle-type engine. The Expander cycle design provides high performance and reliability at low cost, while also giving the new upper stage multiple restart capability. An extendable nozzle will give VINCI a specific impulse of 464 sec. in vacuum.

This paper provides a short history of NASA Stennis Space Center's Test Technology Laboratory and briefly describes the variety of engine test technology activities and developmental project initiatives. Theoretical rocket exhaust plume modeling, acoustic monitoring and analysis, hand held fire imaging, heat flux radiometry, thermal imaging and exhaust plume spectroscopy are all examples of current and past test activities that are briefly described. In addition, recent efforts and visions focused on accomodating second, third, and fourth generation flight vehicle engine test requirements are discussed.

During the period April 1995 to October 1997, the National Aeronautics and Space Administration (NASA) sponsored the Magnetohydrodynamics Accelerator for Research Into Advanced Hypersonics (MARIAH) Project. The objective of the project was to evaluate MHD as a driver technology for hypersonic ground test facilities. Test requirements developed in consultation with NASA specified that the technology should be capable of supporting near full-scale engine testing at dynamic pressures up to 2,000 lbf/ft2 and free stream Mach numbers up to 16. Test durations of tens of seconds to minutes were also specified. The near full-scale requirement implies large test section areas, large flow rates, and extremely high electric power. A technology evaluation included a review of past United States and Russian magnetohydrodynamics (MHD) technology development, detailed analysis and computational simulation of several configurations of MHD accelerators, and two major experimental efforts directed at measurement of electrical conductivity in seeded and unseeded high pressure air. One of the significant findings of the MARIAH Project is that MHD accelerators, which rely on thermal ionization of an alkali metal to achieve the requisite conductivity, have a restricted pressure-temperature range of operation. Pressures of at least 100 atm and temperatures of 2,500 K or higher are required for this mode of MHD channel operation, irrespective of seed material. This is due in part to constraints on entropy dictated by the targeted test section conditions. The minimum temperature requirement of 2,500 K is determined by electrical conductivity considerations. This temperature-pressure range is difficult to achieve using conventional arc heaters as primary drivers. Consequently, alternative nonequilibrium schemes for creating and sustaining the electrical conductivity were investigated. Unconventional drivers in the form of ultrahigh pressure (UHP) gas piston drivers were also evaluated. This paper discusses the major activities and technical findings, concluding with specific recommendations for future research.

Graphite epoxy flat panels were fabricated by three different processing techniques then tested by three different tests to determine what effect processing has on the mechanical properties of a composite structure. The flat panels were a hand lay-up of graphite unidirectional tape with a wet epoxy matrix. Flat aluminum panels were used to sandwich the structure. The panels were oven cured at 300 degrees Fahrenheit, vacuum bagged and oven cured at 300 degrees Fahrenheit, and autoclave cured at 300 degrees Fahrenheit and 180 psi. The thickness of the panels fabricated was dependent on the test requirements. The three tests were ASTM D3410 for compressive properties, ASTM D2344 for interlaminar shear strength and the double v-notch or losipescu for shear properties. The results indicated a significant increase in interlaminar shear properties with autoclave curing and minor increases in compression modulus with vacuum bag curing. The shear modulus was slightly higher with vacuum bag curing.

The design of most military equipment must reflect the potential for combat almost anywhere in the world. Climatic presentations for this purpose have been developed for the recently completed Military Standard 210C (MIL-STD-210C), 'Climatic Information to Determine Design and Test Requirements for Military Systems and Equipment'. This document contains data for many meteorological elements and combinations encompassing the worldwide surface environment, regional surface environments including the maritime environment, and the worldwide air environment up to 80 km. This paper addresses the development and interpretation of these climatic presentations and provides guidance on how they should be used to establish design and test requirements.

Apollo Lunar Module Test Program Management, discussing test requirements optimization, control, planning, etc