XA/EVA Project Office Weekly Activity Report October 4, 2001
XA/EVA Project Office Weekly Activity Report October 4, 2001
Closure of EMU Ground Support Equipment (GSE) Ignition Incident:
On September 28, 2001, Hamilton Sundstrand presented to the JSC/WSTF community, the findings and corrective actions for the Hamilton Sundstrand combustion incident that occurred on May 7, 2001. This incident involved a contained ignition within a regulator on “Rig 12,” a high-pressure oxygen test stand that operates at greater than 8000 psi. The investigation revealed that the most probable cause of the ignition was flow friction due to leakage across a damaged seal between the supply and vent on the self-venting regulator. Closure of this investigation required implementation of several preventative and corrective actions to be implemented by the contractor. These included flushing and certifying the cleanliness of the flight hardware attached to the GSE during the incident, revising detailed assembly and test procedures to ensure quality seals are properly installed in the future, and improving training programs for technicians working on “technique sensitive” regulators. The meeting resulted in a community consensus on closure of the failure and resumption of processing flight hardware on the rig in question.
Inc3 CoER Contamination
The EVA community is continuing preparations to support EVA 2 (the first ISS-3 EVA) Monday October 8, 2001. On-orbit preparations included destow of foot restraints from launch position on egress ladder, checkout of suit and DC-1 systems. On-orbit briefing of crew for specific tasks has been conducted. Remaining briefings will take place October 4-7, 2001. The IMMT EVA Readiness Review was completed on October 3, 2001. Remaining open issues/work for the October 5, 2001 IMMT include Energia status of Orlan communications, suit and telemetry checkout, status of inclusion of video camera in EVA 2 activities, agreement on tox level three IVA cleanup procedures (contingency) and confirmation of the operational approach to avoid deliberate contact with any visible contamination. Agreement was reached that the EVA crew would stop and report to MCC-M any visible residue on MLI blankets covering docking target and passive Kurs antenna prior to proceeding with task. After review of CEIT closeout photos and discussion with Energia experts, the EVA team agrees that the task has been designed to minimize risk of contact with potential contamination. Agreement to use towels and /or jettison blankets in event of contamination was also reached. There are currently no other issues that would affect the implementation of EVA 2 as planned.
EVA Helmet Interchangeable Portable (EHIP) Light to EMU RF Camera Assembly (ERCA) Fit Check
During tool-to-tool fit checks of the EHIP lights to ERCAÕs on STS-108/UF-1, the fastener on the camera would not fully engage into the threaded helicoil on the lights. Minor repairs were made to the helicoil and the fastener, but a subsequent fit check was unsuccessful. Consequently, the helicoil and fastener were both replaced and the interface passed the fit check. A Failure Investigation Action Report (FIAR) was generated on the ERCAÕs to document the difficulty achieving an acceptable interface. All associated hardware flying on STS-108/UF-1 has been successfully fit checked.
Adaptive Payload Carrier (APC) Loads for the Hubble Space Telescope (HST)
The Multi-Use Lightweight Equipment (MULE) Carrier, the HST Portable Foot Restraint (PFR) and Adaptive Payload Carrier (APC) had to be relocated from Port Bay 13 to Port Bay 10 because of interferences. New stress calculations initially indicated negative margins on the HST PFR in Port Bay 10. Subsequent work recalculating stress loads using more realistic models of the APC, and HST PFR were completed. The new calculations show positive margins on all hardware and the hardware can now be certified for Port Bay 13 installation.
Original signed by:
Stephen C. Doering
Deputy Manger
