Status Report

XA/EVA Project Office Weekly Activity Report October 25, 2001

By SpaceRef Editor
October 25, 2001
Filed under , ,

Test Readiness Review (TRR) for NASDA Weightless Environment Training (WETS) Ops #3 Testing

EVA Project Office personnel chaired a TRR for the WETS Ops #3 planned to take place on November 5-23, 2001. NASDA personnel presented an overview of the historical precedence of joint NASA-NASDA neutral buoyancy EVA testing in the WETS facility, and the current agreements for the Ops #3 Test as well as a summary of the results from the NASDA-internal Test Readiness Review conducted on October 5, 2001, at the Tsukuba Space Center. NASDA stated that all facility and personnel training preparations are either complete or scheduled for completion in time to support the planned schedule, and that there are no open issues.

Engineering Directorate personnel summarized the status of the comprehensive review currently in work by Hamilton-Sundstrand (HS) and ILC personnel to review the configuration of the NASDA-owned EMU hardware, and the current procedures used to process both NASDA and NASA-loaned EMU space suit equipment in Japan. All open actions are scheduled for closure prior to shipping any NASA-owned EMU components to Japan for the Ops #3 Test. The TRR determined that an additional JSC EMU Engineer/Technician would attend the testing to support any space suit issues. Discrepancy Reports will be initiated to cover any issues found as a result of the reviews completed by HS and ILC personnel, and daily reports will be provided to NASA during the test. The TRR determined that the test was ready to proceed pending closure of the defined open actions.

Increment 5 Baseline

The ISS-5 Baseline Briefing was presented to the EVA Configuration Control Board (CCB) on October 12, 2001. The ISS-5 crew launches on ISS Assembly Flight UF-2 and returns on ISS Assembly Flight 11A. There is currently one EVA planned during this Increment. The EVA will be performed by the ISS-5 crew in Orlan spacesuits out of the DC1 and will remove the Service Module Debris Shields from the temporary stowage location on PMA 1 and install them on the Russian Segment Service Module. The baseline was approved by the EVA CCB.

ISS-3 EVA #3

ISS-3 EVA #3 was successfully completed on October 15, 2001 in Orlans out of DC-1. Orlan and DC-1 systems functioned nominally for the EVA. All planned objectives for EVA #3 were met. Tasks completed included Kromka installation at the port thruster location, NASDA Space Environment Exposure Devices (SEEDÕs) deployment, exchange of flag experiments and closeout photo documentation. The EVA crewmembers reported no visible contamination around or in the thruster area. The Orlan gloves were bagged after the EVA per procedures. In preparation to close the hatch, it appeared to be stuck in the temporary location but was subsequently freed. The latches were also cycled due to concerns over debris. Repress went nominally, and the EVA concluded at 5 hours and 52 minutes in length.

Display and Control Module (DCM) Anomaly

On Wednesday, October 11th, USA was preparing EMU s/n 3014 for STS-108 (UF-1). During a routine electrical test of the Display and Control Module (DCM) the technicians noted an electrical burning smell and subsequently observed a slight puff of smoke emanating from the top of the DCM. All DCM operations, on ground and on-orbit, were immediately halted. The subsequent investigation has revealed that a zener diode had shorted. This diode is used for transient voltage suppression to protect the downstream current limiting circuitry within the DCM. The direct short was a result of re-flow of the solder within the component causing a metalization path and the breakdown of the silicone dielectric. This was most likely due to sustained over-voltage input from the GSE power supply. The GSE has been found to operate nominally, however the equipment used to perform this test did not have any over-voltage protection. The most probable cause for the anomaly has been deemed to be an erroneous setting or accidental overshoot on the input voltage. Remedial corrective action has centered on modifying the GSE to incorporate over-voltage protection and modifications to the procedures to further protect the hardware when the input voltage settings are changed. No impacts to future missions or on-orbit operations are expected as a result of this anomaly.

Original Signed By

G. Allen Flynt


SpaceRef staff editor.