[FPSPACE] NASA WATCH: 5A To Slip 30-60 Days

JamesOberg@aol.com JamesOberg@aol.com
Tue, 5 Sep 2000 14:54:48 EDT


NASA WATCH ==  5 September 2000: 
Launch of STS-98/ISS Flight 5A delayed. STS-92/ISS 3A may slip too. 
 
  Editor's note: according to sources at NASA, the launch of STS-98/ISS 
Flight 5A (US Lab delivery) will be slipped 30-60 days as the result of PCS 
(Portable Computer System), CCS (Command and Control Software) , and NSC code 
problems. 

   Meanwhile, a temperature (Hall effect) sensor on the backup CMS (Control 
and Monitor Subsystem) failed. This has been attributed to large stresses 
associated with thermal cycling. There is apparently little if any time no 
time to fix this problem since the CMGs (Control Moment Gyroscopes) are 
schedued to be launched on STS-92/ISS 3A at the end of September 2000. 

   Three options are currently under consideration at the ISS Program Office: 
Launch the CMGs with this known problem, and make some substantial changes to 
the STS-98/ISS Flight 5A mission's GN&C (Guidance, Navigation and Control) 
software and make wiring modifications to the Z1 Integrated Truss Structure 
(ITS). 
Postpone the launch of STS-92/ISS 3A until the CMGs canbe repaired. Thsi 
could take cause a 12 to 15 month launch delay. 
Take the CMGs off of the Z1 Integrated Truss Structure and launch the CMGs 
larter when they are repaired. 

It is expected that NASA will chose the first option. 
=======

JimO adds: I also hear that non-compliant fiber optics will be launched 
anyway on other modules, and will require change-out on orbit before it can 
function to spec levels. Back in 1990-1, when I was on the Blue Ribbon Panel 
for the Fisher-Price Committee for EVA Maintenance, we looked at the Freedom 
design and added in predictable ORU failure rates and concluded the design 
would NEVER be completable -- that it would stall out at about 70% complete 
and all subsequent up-cargo would be replacement parts for failing 
components. I wonder if the improved ISS design will ever reach that 70% 
level?

JimO: I also wonder if this means Expedition-1 will stay longer on orbit? The 
Russians want to delay the next Progress until AFTER the crew gets aboard 
because it's the first side-docking, and having TORU backup seems prudent (I 
agree). But critical crew equipment -- including toilet hardware -- 
supposedly is on board that supply ship.