03 Mar 2010

The critical design review (CDR) took place 11-14 January at Northrop Grumman's facility in Redondo Beach, California. In addition to validating the sunshield design during the CDR, it was shown that the sunshield design meets the thermal, deployment and stray-light targets that had been set. The CDR also provided an opportunity to evaluate and approve the sunshield manufacturing and test plans. With the completion of these milestones the sunshield flight model can begin the manufacture and test phase.

Photo of the one-third scale sunshield membranes undergoing final inspection at the Nexolve facility in Hunstville, Alabama, U.S.A.  Credit: Nexolve

In preparation for the critical design review, 18 separate sub-assembly design audits were conducted on this complex system with the goal of validating the sub-assemblies at the system level and evaluating the points where they interface.

In addition, prior to the CDR, a thermal test campaign (running from 23 November to 19 December 2009) was performed on a one-third scale model of the sunshield. The main goals of this campaign were: to test the sunshield's ability to block heat, and to verify computer models that will be used to extrapolate the results from the thermal performance of the scale model to that of the full-size sunshield. (Further details of these thermal tests can be found in the article "Turning up the heat: Finding out how well the Webb telescope's sunshield will perform" at NASA's JWST site; see related link in the right-hand menu).

The Webb telescope is a joint project of NASA, ESA and the Canadian Space Agency. Northrop Grumman is designing and developing the Webb spacecraft under contract to NASA Goddard Space Flight Center.