GAO Warns JWST Cryocooler Poses Risk of Schedule Slip

GAO Warns JWST Cryocooler Poses Risk of Schedule Slip

The Government Accountability Office (GAO) issued its third annual congressionally-required assessment of the status of NASA’s James Webb Space Telescope (JWST) today warning that the project’s schedule is at risk particularly because of challenges developing its cyrocooler.

GAO acknowledged that JWST program officials report that the space telescope’s overall schedule reserve is above its plans and standards, but pointed out that with four years until launch, NASA is only now beginning to integrate and test two of the five elements and major subsystems and this is the time period where problems are likely to be found.  Therefore “maintaining as much schedule reserve as possible … is critical.”

JWST also has “limited short-term cost reserves” to deal with potential schedule slips, GAO found.  Northrop Grumman Aerospace Systems (NGAS) is the prime contractor for JWST, and GAO criticized the cost risk analyses used by NASA and NGAS because “they do not account for many new risks identified since 2011.”  GAO stressed that cost risk analyses must be continually updated to ensure reliability and that is part of adhering to cost estimating best practices. 

It recommended in the report that NASA follow best practices in cost estimating.  NASA “partially concurred” with the recommendation. NASA’s comments are published as an appendix to the report and say basically that it agrees it should follow best practices and is already doing so. 

JWST is described as a successor to the Hubble Space Telescope although it operates in different wavelengths (infrared rather than visible) and will be positioned at the Earth-Sun L2 Lagrange point (rather than in earth orbit).   It has a sunshade to protect it from the Sun and is passively cooled by exposure to space environment.  However, one of its instruments, the Mid-InfraRed Instrument (MIRI), requires additional cooling, which will be provided by a first-of-its-kind cryogenic system — a cryocooler. 

GAO warned that the JWST project “continues to face major technical challenges building the cryocooler that have significantly delayed delivery of key components, have made it the driver of the project’s overall schedule or the project’s critical path, and required the use of a disproportionate amount of project cost reserves.”  Since the program was replanned in 2011, the cryocooler has experienced 150 percent cost growth and “is contributing to the project’s limited cost reserve status” for FY2015.

Past cost overruns and schedule delays in the JWST program have caused concern at NASA and in Congress.  JWST is managed by NASA’s Goddard Space Flight Center in Maryland and has strong support from Sen. Barbara Mikulski (D-MD), who currently chairs the Senate Appropriations Committee.   Even her support was tested in 2010 with the announcement of additional cost growth, leading to a study headed by JPL’s John Casani that concluded the problems were primarily managerial, not technical.  Consequently, NASA restructured how the program is managed and developed a new life-cycle cost estimate.  The Casani report estimated that the cost would grow from $5.1 billion to $6.5 billion and the launch date would slip from 2014 to 2015, but after further analysis, NASA concluded the development cost would be $8 billion, with launch in 2018. 

Congress capped JWST development at $8 billion.  Another $800 million is needed for operations, yielding a lifecycle cost estimate of $8.8 billion.  That is based on launch in 2018.  JWST is being launched on an Ariane rocket as part of an international cooperative agreement with ESA (meaning NASA does not pay for the launch).

JWST is one of NASA’s top three priorities according to an agreement reached between the White House and Congress in 2011. The other two are the International Space Station and commercial crew, and the Space Launch System and Orion.


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