Universities Space Research Association Page 1 HAWC High-resolution Airborne Wideband Camera How Are We Coming along? Bob Pernic Project Manager Al Harper Principal Investigator April 2009 Review

Universities Space Research Association Page 2 Development Status Test Cryostat :Retired Flight Cryostat :Operational Housekeeping System :Operational ADR :Operational OMS :Operational Detector :Operational Electronics :Operational. Software :General User interfaces coming along nicely. Data reduction software in development. Internal Optics :Operational Fore-optics and calibration system: Detailed design underway Flight System Integration:Work in progress

Universities Space Research Association Page 3 Airworthiness Status (Similar to recent previous reviews) Cryostat, ADR, & OMS Assemblies: approved Electronics, Detector, & Optics Assemblies: Resubmission on hold Revised drawing package:Being updated System Safety Analysis:SSA initiated Electronics CADR:80% completed

Universities Space Research Association Page 4 December 2008 Status SubsystemTechnicalBudgetScheduleComment Cryostat Operational Optics Operational Detector Operational Electronics Fabrication of full complement complete Software No outstanding issues Integration & Testing Just completed two months test with fully integrated flight systems Airworthiness We understand the requirements ICP (Integration Commissioning Plan) Thinking about it.

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Universities Space Research Association Page 6 Fore-optics Design

Universities Space Research Association Page 7 March/April 2009 Cold Tests (Preliminary results; tests still underway.) Electronics: Integrated, tested, and debugged complete data acquisition system (full complement of 384 channels). Noise performance meets specifications. Battery power supply for analog electronics failed because of short in manufacturer-supplied battery pack. We built up an AC power supply for current lab tests and are investigating battery problem. In lab, AC power supplies do not seem to increase noise. We may be able to fly with AC supplies, but need battery backup, at least for early flights. Encountered noise problem with externally supplied sync signal. We diagnosed and fixed the problem. Current HK and OMS cables have known grounding problems. Need to repair and/or replace before next tests. Cryogenic systems Shorted temperature sensor in middle JFET drawer initially prevented operation of two detector rows. Developed work-around by disabling one detector and re-wiring both heater circuits to use a single sensor. Performance of ADR heat switch has decreased. Adjusted cycle parameters to compensate. We are achieving full cycles and see little effect on ADR hold time. Suspect diffusion of helium gas through side-walls of switch assembly. Goddard cryogenics group will refurbish the switch before next cold tests. Little improvement in thermal performance of mechanisms after installation of superconducting motors. However, both new and old motors meet basic operational requirements. Detector performance and optics Point-spread functions for all bands. Complete set of multi-temperature iv curves to determine detector model parameters. Hot-plate signals vs. bias for all bands and pupils. Noise vs. bias for all bands and pupils. Successfully tested electrically modulated point sources to be used in fore-optics boresight system. New 200-mK baffle reduced detector backgrounds from scattered light. However, there are still some low-level ghost images from diffraction of light from out-of-field point sources. Computer systems and software New master computer and new parallel interface cards have improved system performance. System functions well with full 384- channel data electronics system. Data acquisition software now working in client/master mode. Overall operation has been reliable. Debugging and user-interface development are proceeding. Prototype data pipeline components tested with laboratory data.

Universities Space Research Association Page 8 Issues to be addressed prior to next round of tests Fix electrical shorts in cold JFET drawer Fix ground problems in HK and OMS cables Rebuild interface from external sync source to data electronics based on improved design developed during current cold tests Fabricate box for flight AC power supplies Fabricate spare Timing and Control, Auxiliary Analog, and Chopper Interface boards Put power Data Electronics power distribution board, interface connectors, and cooling system into final flight configuration Resolve issues with batteries Refurbish ADR heat switch Review performance of superconducting motors (less improvement over copper-winding motors than anticipated) Review design of 200-mK baffle. Investigate external field stop. Continue to develop/refine data acquisition and data pipeline software

Universities Space Research Association Page 9 Issues to be addressed prior to next round of tests Mitigate electrical shorts in the cold JFET - GSFC will assist. Although stray light from 200-mK baffle appears to be eliminated - further data reduction is required to determine effectiveness Electronics are functional and noise levels appear as expected. Some minor changes may be required Heat generated by Optical Mechanical System’s Super conduction Motors is problematic. Have entered into discussion of issues with the motor manufacturer to mitigate. Continue to develop/refine data acquisition software

Universities Space Research Association Page 10 HAWC Trimester Look Back Overview HAWC MilestoneCompleted Yes/No HAWC Critical Path Item Yes/No Comments Run fully integrated systems tests Yes Results of tests look good. Some systems require further attention Detailed design of warm optics. No Delay caused by reduction in budget Complete MCS integration tier 4 NoYesProject office dependent Continue data pipeline and analysis software YesNoWork in progress Continue airworthiness certification YesNoStarting this summer as scheduled

Universities Space Research Association Page 11 HAWC Trimester Look Ahead Overview HAWC MilestoneCompleted Yes/No HAWC Critical Path Item Yes/No Comments Write report on latest round of system tests No Some data reduction has been taking place while testing was in progress Minor debug electronics No Work in progress Complete detailed design of warm optics. No Work in progress Complete S.W.ClientNoYesTo be completed next GFY Work in progress Complete MCS integration tier 4 NoYesNot scheduled at this time Data analysis softwareNo Work in progress NASA flight certificationNo Work to begin the first of this year Modifications of OMS & Geneva mechanisms NoYesSome minor modification needed

Universities Space Research Association Page 12 HAWC Budget GFY09 Funding available for year2009$900,000 Total invoiced this year Approximate expenditures to date Projected Expenditures at end of FY$900,000 Projected carry over $0

Universities Space Research Association Page 13 HAWC Milestone Schedule

Universities Space Research Association Page 14 Summary Based upon our new funding levels, HAWC will be: - Moved to NASA/Dryden in mid 2012, to commence EMC testing and airworthiness certifications. (We are still grasping with the effects of the newly proposed schedule budget). -We expect to continue hardware,software and document development into Ready for science in Commissioned as Facility Science Instrument in 2013.