Apr 12 2011

US-GAO: JSF Not Fully Demonstrated a Stable Design

Gepubliceerd door JSFNieuws.nl om 20:58 onder Global F35 News

Early April 2011 a new US-GAO report about the JSF program has been released.
US GAO expressed concerns about the progress the fact that the JSF Program has still not fully demonstrated a stable design and mature manufacturing processes as it enters its fifth year of production:
After completing 9 years of system development and 4 years of overlapping production activities, the JSF program has been slow to gain adequate knowledge that its design and manufacturing process are fully mature and ready for greater levels of annual production. The JSF program still lags in achieving critical indicators of success expected from well-performing acquisition programs. Specifically, the program has not yet stabilized aircraft designs—engineering changes continue at higher than expected rates long after critical design reviews and well into procurement, and more changes are expected as testing accelerates. Also, the aircraft and engine manufacturing processes are not yet mature enough to support efficient production at higher annual rates and substantial improvements in the global supply network are needed. Further, the growth in aircraft reliability—crucial for managing life-cycle costs—has not been demonstrated to the extent planned by this time.

JSF Not Yet Stabilized Aircraft Designs

Engineering drawings released since design reviews and the number and rate of design changes are excessive compared to plans and best practices. Critical design reviews were completed on the three aircraft variants in 2006 and 2007 and the designs declared mature, but the program continues to experience numerous changes. Since 2007, the program has produced 20,000 more engineering drawings, a 50-percent increase in total drawings and about 5 times more than best practices suggest. In addition, changes to drawings have not decreased and leveled off as planned. Figure 2 tracks and compares monthly design changes and future forecasts against contractor plans in 2007. The monthly rate in 2009 and 2010 was higher than expected and the program now anticipates more changes over a longer period of time—about 10,000 more changes through January 2016. We expect this number to go up given new forecasts for additional testing and extension of system development until 2018.

Excessive design change rates

A key indicator of a product’s maturity is the stability of its design. The number of engineering drawings released and subsequent changes provide indicators of the maturity of the design. Engineering drawings are critical because they communicate to the manufacturer and suppliers how the part functions, what it looks like, and what materials and critical processes are used to build the product. Best practices suggest 90 percent of a product’s engineering drawings be released by the critical design review. Late engineering drawings and high levels of changes often indicate a lack of understanding about the design, and can cause part shortages and inefficient manufacturing processes as work is performed out of sequence. Some level of design change is expected during the production cycle of any new and highly technical product, but excessive changes raise questions about the JSF’s design maturity and its readiness for higher rates of production.

Impact from required design changes are significant

With most of development testing still ahead for the JSF, the risk and impact from required design changes are significant. Acquisition programs typically encounter higher and more substantive changes as a result of discovery and rework during development flight and ground testing. Future changes may require alterations to the manufacturing process, changes to the supply base, and costly retrofitting of aircraft already produced and fielded. A key cost driver for the program has been the higher than expected effort needed to address design related issues. The contractor has not been able to reduce engineering staff as fast as expected. DOD’s restructuring actions recognize these issues and added time to development, more flight testing, and reduced procurement. Additional changes are likely as development flight testing continues

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