PAYLOAD TEST REQUIREMENTS
|Publication Date:||6 June 2018|
The purpose of this NASA Technical Standard is to provide an Agency-wide basis from which test programs are developed for NASA payloads. The document defines a standard set of flight hardware test requirements which provide the necessary verification of design adequacy and flight worthiness of NASA spacecraft. Compliance provides consistency across the Agency and its contractors, facilitating the sharing of hardware between Centers and programs. Compliance also provides a basis for establishing a baseline pedigree for the "qualification by similarity" evaluation process for "heritage" hardware without the need to consider the variability of test requirements.
This NASA Technical Standard includes selected environmental exposure tests for flight hardware. The NASA Technical Standard has been developed for payloads that will operate in Earth's orbit but may be tailored to include other operating environments. The tests included are generally regarded as the most critical and the ones having the highest cost and schedule impact. This NASA Technical Standard also includes functional demonstration tests necessary to validate the capability of the hardware to perform its intended function (with and without environmental exposure). This NASA Technical Standard specifies test levels, factors, margins, durations, and other parameters. In some cases, these specifics are expressed statistically or are referenced in other NASA standards.
This NASA Technical Standard is approved for use by NASA Headquarters and NASA Centers and Facilities, and applicable technical requirements may be cited in contract, program, and other Agency documents. It may also apply to the Jet Propulsion Laboratory (a Federally Funded Research and Development Center (FFRDC)), other contractors, recipients of grants and cooperative agreements, and parties to other agreements only to the extent specified or referenced in applicable contracts, grants, or agreements.
This NASA Technical Standard applies to all NASA payload hardware developed in-house or under contract that is launched on expendable or reusable launch vehicles (both free-flyer and attached payloads). This NASA Technical Standard defines a baseline test program which is applicable to all NASA payload hardware regardless of mission risk classification as defined in NPR 8705.4, Risk Classification for NASA Payloads. However, the test program may be tailored based on mission success criteria and risk classification following the Center's defined risk philosophy and with approval from the delegated Technical Authority. The levels of assembly for which this NASA Technical Standard applies are the payload, modular subsystem (which includes large instruments), and component. Small instruments may be treated as components. This NASA Technical Standard defines a baseline test program for NASA payload hardware. In general, no distinction has been made between "human-rated" and "robotic" missions. Human-rated flight systems may be subjected to additional verification and/or safety requirements that are consistent with the established risk levels for mission success and flight crew safety not covered by this NASA Technical Standard.
This NASA Technical Standard excludes payloads launched on sounding rockets, balloons, and aircraft, as well as the launch vehicle hardware itself. Also excluded from this NASA Technical Standard are tests that may be required below the component level of assembly such as material testing or electronic part screening.
This NASA Technical Standard is developed for the typical NASA protoflight payload wherein one payload is built and serves to qualify the design and is also the flight article. It also recognizes the need to define the mission-unique environment for each test discipline. This environmental definition ensures the tailoring of test requirements to the environmental envelope encountered during the payload's total lifetime, considering phases such as ground handling, launch, and in-space operations.
The principal objective of the test program is to demonstrate the system's ability to collect scientific data and perform specific remote operations rather than meet rigid general requirements. Certain environments and functions cannot reasonably be simulated on Earth because of factors such as size, zero-gravity limitations, and interface boundary conditions. Tailoring the test program, with supplemental analysis, is appropriate in such cases. This NASA Technical Standard is generally not retroactive from the approval date for hardware already under contract.
Verifiable requirement statements are designated by the acronym PTR (Payload Test Requirement), numbered, and indicated by the word "shall"; this NASA Technical Standard contains 67 requirements. Explanatory or guidance text is indicated in italics beginning in section 4. To facilitate requirements selection by NASA programs and projects, a Requirements Compliance Matrix is provided in Appendix A.