XA/EVA Project Office Weekly Activity Report 10 August 2000
O2 Contamination Status
The EMU secondary oxygen pack (SOP) contamination recovery team continues to make progress to ensure EMU readiness for STS-106. Two test failures have occurred during the past week, which have caused a loss of several days of margin against the original recovery plan. However, the current plan still supports flight and a nominal EMU installation and checkout at KSC on August 30. The first failure occurred during leak tests performed at Hamilton Sunstrand on SOP assembly S/N 1016. The test indicated a leak between the SOP bottle and the manifold seal. Investigation revealed a fiber on the seal. This issue was corrected and the SOP is back in testing. The second failure occurred during performance testing of SOP assembly S/N 1018. Performance of the SOP was off nominal throughout the range of flow rates. This issue is still being investigated.
Investigation into the root cause of the contamination continues to progress in preparation for the STS-106 Flight Readiness Review (FRR). All certification documentation related to this issue is on schedule for completion prior to the FRR.
2A.2b EVA Status
The 2A.2b EVA Team participated in the Orbiter Rollout Milestone Review and the Payload Readiness Review last week for STS-106. The EVA Team has no issues. In addition, the STS-106 Bench Review was held on August 4th. Minor crew squawks are being closed out this week. The EVA CoFR 2 review was held on August 7th and supported by our EVA Russian partners. All issues identified at the CoFR review will be closed out by the Flight Readiness Review on August 29th.
Increment 2 Hydrolab Training Status
Hydrolab training for Increment 2 was due to begin on August 1st, but was delayed due to problems getting the water heated following the recent repair work there. Engineering runs were performed on August 7th and 9th. The first training session will take place on August 11th. To compensate for the slow start there will be three training runs the week of August 14th, and two training runs per week thereafter. A total of eight training runs (4 prime/4 backup) are planned in this session, and all are for EVA 1 and 2 tasks.
Small EMU Preliminary Design Review
The small EMU arm preliminary design review (PDR) was held on July 25. This PDR covered the upper arm, small arm bearing, and lower arm. The following recommendations from the review were approved: 1) continue with development and testing of the new “wedge design” upper arm concept, 2) mock-up and test two concepts for small arm bearings and recommend a concept by September, and 3) continue with development and testing of a small arm bearing lower arm with a quick disconnect feature. A risk assessment indicated none were high risk.
3A Status
Z1 Crew Equipment Interface Test (CEIT) Issues – The STS-92 (3A) CEIT for cargo element Z1 was conducted on July 31, 2000. The following issues were identified: 1) Rocketdyne Truss Attachment System (RTAS) Bolt #3 Area Clearances – A shroud strap appears too close to the bolt. The concern is that damage to the shroud may occur if this strap gets wrapped around the socket of the EVA power tool. Also, the tool stack on this bolt could cause the power tool to be too close to a Control Moment Gyro. Plans are to repeat a tool to interface fit check of this bolt using high fidelity sockets, 2) interference between cables to the Shuttle Wireless Instrumentation System and the Z1 handrail – The cable has subsequently been rerouted to fix the problem, and 3) tie wrap interference with the Baseband Signal Processor (BSP) radiator cover – the tie wrap is used to hold the Z1 stowage bin onto a handrail stanchion. The tie wrap could keep the BSP cover from being removed during a maintenance task. The planned solution is to replace the tie wrap with an EVA wire tie then route it out of the way. All Z1 CEIT issues will be closed by 8/18/00.
Z1 to Orbiter Grounding Issue – Z1 grounding tests at KSC recently determined that the planned ground path between the Orbiter and Z1 is inoperative. The path was through the Z1 keel which is not possible since there is no ground path between the keel and Z1. The fix is to provide grounding through the payload retention latch assembly and the Z1 trunnions by inserting a wiper. This could have potential sharp edges and could be a snag hazard to the EVA crew. The Vehicle Integration Test Office will examine the hardware for hazards this week at KSC.
