Description of Driving Event:
Materials Obsolescence, Parts Obsolescence and Environmental Regulations Issues Cause Disruptions in Stable Shuttle Ground Operations Processes
Lesson(s) Learned:
The Space Shuttle program has experienced some difficulties when stable work processes were altered to counter obsolescence or meet new environmental requirements. The simultaneous change in pressure sensitive adhesive and cleaning wipe in the RSRMs to meet environmental regulations is one example.
Recommendation(s):
The Space Shuttle program should not alter long-established and stable processes without defining and completing an adequate test program. If changes in stable and well-characterized safety-related hardware and processes are being driven by environmental requirements, NASA should consider seeking waivers of these requirements rather than altering a proven design.
Evidence of Recurrence Control Effectiveness:
The SSP has been and is committed to not altering long-established and stable processes without defining and completing an adequate test program. The program has long had requirements governing the recertification of hardware in the event of either a hardware design change and/or a process change(s) that affect form, fit, function, safety, and/or reliability. However, the program has authorized a recent requirement change (reference PRCB Directive S071024DL) to provide a program-level review of all hardware and/or process changes whose certification is based solely on analysis. This requirement change necessitates a program assessment of the rationale for specifically defined changes whose recertification is based solely on an analysis, as opposed to those where the recertification is based on the performance of an adequate test program. It is felt that compliance with this new requirement will assure that changes to long-established and stable process changes are only implemented with adequate and appropriate recertification. For any safety-related hardware or process change that is being driven by environmental requirements, NASA includes in its initial assessments the appropriateness of seeking a waiver to the requirements that are causing the change. Where such an assessment substantiates the appropriateness of a waiver, then that waiver shall be sought. The SSP adopted a policy that balances flight safety and environmental protection goals in SSP letter MS-96-071, dated September 16, 1996. The SSP manager specified: (1) obtain long-term waivers for materials essential to safe Space Shuttle operations where functionality cannot be verified; (2) obtain long-term waivers for materials where no replacements exist; and (3) continue to pursue identification and certification of replacement materials.
Documents Related to Lesson:
N/A
Mission Directorate(s):
- Space Operations
- Exploration Systems
Additional Key Phrase(s):
- Aerospace Safety Advisory Panel
- Environment
- Ground Operations
- Hazardous/Toxic Waste/Materials
- Parts Materials & Processes
- Policy & Planning
- Safety & Mission Assurance
- Spacecraft
Additional Info:
|
