JWST Passes TNAR

On March 23, 2007, the Non-Advocate Review Team (NRT) submitted a short memorandum to NASA Headquarters stating that the Technology Non-Advocate Review (T-NAR) held on January 30-February 1 had successfully met its objectives. As described in the Spring 2007 STScI Newsletter, the Project had shown that 9 of the 10 key enabling technologies needed for the Webb development had been demonstrated to meet their performance goals in the appropriate launch or flight-like conditions. These included the following:

Near Infrared Detectors (HgCdTe)
SIDECAR ASIC ( the cryogenic controllers and signal processors for the detectors)
Mid-infrared detectors (Si:As)
Near Infrared Spectrograph (NIRSpec) Microshutters
Cryogenic heat switch
Sunshield membrane and coatings
Wavelength sensing and control mechanisms and software
Primary mirror Be segments and mounts
Stable cryogenic backplane structure

The only technology development that had not yet met its goals was the Mid-Infrared Instrument (MIRI) cryocooler, which had yet to meet its cooling and vibration-control performance requirements. The NRT's report agreed with the Project's readiness assessments for the nine successful technologies listed above and stated that "an [new] approach was identified and actions were taken to bring the MIRI cryocooler technology to TRL-6 maturity. This has been successfully completed." While the NRT had identified "residual risks" for some of the items, they concluded that "the TNAR, and subsequent activities, to have demonstrated that the TRL-6 criteria for all 10 enabling technologies have been met, and that, barring any unforeseen circumstances, we [NRT] do not intend to revisit the technology readiness of those technologies at the NAR [Non-Advocate Review, now scheduled for late March 2008]." NASA Headquarters has accepted the NRT report, clearing the way for the JWST Preliminary Design Review/NAR in March 2008.