posted November 30, 2012
In response to the JWST cost (> 15%) and schedule (> six-month slip) breach, NASA prepared for a future decision on the JWST by seeking an analysis of alternatives (AoA) to the JWST baseline and a preliminary risk assessment. NASA Headquarters tasked Aerospace to perform both the AoA and PRA.
In performing the AoA, Aerospace considered many alternatives, including ground, airborne, space, and JWST variant telescopes. Figures of merit (FOMs) were determined to measure the performance, risk, cost, schedule, and availability of the alternatives. A physics-based performance analysis tool was developed to determine the signal-to-noise ratios and other sensitivity-based astronomy FOMs. All the FOM results were normalized and compared to the JWST baseline. Aerospace also presented a preliminary risk assessment of the JWST rebaseline plan at NASA headquarters. The PRA consisted of an independent review and quantification of program risks, identification and quantification of new risks, and an overall assessment of the project’s risk-based joint confidence level cost assessment. The results of the AoA and PRA analyses were folded into NASA’s formal breach report response to Congress in May 2011.