NASA - National Aeronautics and Space Administration

The White Sands Test Facility (WSTF) 2009 Composite Pressure Vessel and Structure Summit is an annual meeting where government agencies, industry, and academia are invited to discuss current fiber-reinforced composite (FRC) technology as it relates to composite pressure vessels and structures. This year the focus will be on knowledge gaps in FRC technology, lessons learned from pressure vessel and structure accidents, and collaboration for the resolution of safety, quality, and mission issues for FRCs.

This is a closed Summit, restricted to U.S. citizens only.

NASA White Sands Test Facility, Las Cruces, New Mexico, Aerial View

Objective

The aerospace and automotive industries are constantly under pressure to use fiber-reinforced composites (FRCs) to produce low-cost, lightweight, and reliable composite pressurized structures (CPSs) and composite pressure vessels (CPVs). Meanwhile, safety regulatory agencies within the DoD, NASA, FAA, and DOT are required to assure that new CPVs and CPSs do not pose an unacceptable risk to agency personnel, the public, or mission objectives.

FRC technology is very fast moving compared to metals. There is a lack of fundamental knowledge in some key areas of material properties, fabrication, testing, modeling, and risk assessment. Due to rapid technology growth, current standards for regulation are vague, overly conservative, or do not uniformly address fabrication processes and test procedures.

Due to the lack of fundamental data, disagreements are sometimes heated between customers, manufacturers, and quality and safety organizations when FRC pressure vessels are chosen for “primary load bearing structures.” The end result is millions of dollars spent to develop and qualify a new or modified design. The lack of standard protocols reduces reliability and is a setback in the innovative push forward of this mission-enabling technology. During the 2009 Composite Pressure Vessel and Structure Summit, an evaluation will be made to determine if an integrated and nation-wide effort to fill in knowledge gaps is needed.

The objective of the 2009 Composite Pressure Vessel and Structure Summit is to discuss knowledge gaps in fiber-reinforced composite (FRC) technology; review applicable regulations; explore lessons learned from FRC pressure vessel and structure accidents; and work with industry, government agencies, and academia to formulate an integrated plan for resolving safety, quality, and mission issues with FRCs.

Scope

The central questions we plan to address at the Summit are:

1. Should the design and quality assurance of hardware be regulated to ensure flight safety of astronauts, pilots, drivers, passengers, ground crews, and the general public? Specifically, hardware that has minimal safety margins and poses an increased risk of failure because of variations in mechanical properties, and hardware that could cause catastrophic damage or loss of life.
2. What current industry safety standards and operation protocols should be employed to guide the regulation and certification of FRC-based composite overwrapped pressure vessels (COPVs), CPSs, and CPVs used in the aeronautics, space, and automotive industries?
3. Are there certification requirements (e.g., CFR Title 14 or 49, AFSPAN91-710, ANSI/AIAA SO-81A, ISO 1119, ISO 14623, NGV2, KNPR 8715.3, CMH-17) detailed with sufficient information to assure safe use of FRC-based COPVs, CPVs, and CPSs?
4. Should long-term strength testing (e.g., stress rupture testing) be considered in the design methodology of a FRC?
5. Do we know enough about the mechanical properties of FRC to establish a meaningful life factor on cyclic life or damage tolerance life?
6. Should we consider the damage tolerance and fracture toughness of the FRC in the design criteria to establish safe life?
7. Do we know enough about the potential failure mechanisms and coupling effects of composites for various ground and flight environments?
8. Should there be different design requirements for constructing resin-based FRCs when different fluids are used, (i.e., gas vs. liquid) to determine long-term stress or pressure rating?
9. Who should be responsible for modifying or developing standards that don't exist for new technology?