STS-122: Atlantis looking good ahead of flight rationale green light

by Chris Bergin

With just over half a month until the launch of shuttle Atlantis on STS-122, her return to a launch posture picks up the pace with a set of Flight Readiness Reviews (FRRs) over the next 10 days.

The FRRs will give a final review of flight rationale, following the replacement of ET-125’s LH2 Feed-through connector – along with other elements of the shuttle that have been sitting on launch pad 39A since November.

**The most comprehensive collection of Shuttle, Ares, Orion and ISS related presentations and mission documentation, plus expansive daily processing documentation and updates are available to download on L2 **

STS-122 L2 Special NOW LIVE. **Click here for sample of L2 menu and content**

**STS-122 Special: 29 Flight Readiness Review (FRR) Presentations, Baselines and Mission Overviews. **Click here for FRR overview articles: Article 1Article 2** Payload Presentations and vast amounts of live, uploaded images and presentations, movies (several) – already 2400 megabytes strong**

**COMPLETE Section – over 1100mbs of presentations – on ECO/Feedthrough Connector issues and troubleshooting, graphical and data based – expansive.**

**LIVE updates on Atlantis STS-122 Troubleshooting Latest**

**LIVE updates on Discovery STS-124 Processing**

 **LIVE news updates on Endeavour STS-123 Processing**

STS-122 ECO related news content: *Scrub 1* – *MMT Debate* – *Scrub 2* – *Hale Memo* – *Forward Plan* – *Culprit Found* – *Tanking Test* – *Repair Options* – *MAF Plan**PRCB Debate* – *Plan Approved* – *Repair Schedule* – *Launch Date* – *New Issue* – *Hale Rallying Call* – *PRCB Launch Dates* – *New Connector Installed* – *Positive Test Results* – *Manifest Impacts* – *Optimism with forward plan*

STS-122 Troubleshooting Latest:

Two FRRs will be conducted, a Level 2 Space Shuttle Program (SSP) on Friday, with the Level 1 FRR to follow on January 30. While these won’t be as large as the original FRRs for STS-122, the main topic of conversation will be the final check on the replacement Feed-through connector installation.

The weather has been the only problematic element of the superb engineering effort to continue Atlantis’ return to a launch posture, as the tank undergoes a period of ‘cure time’ on the TPS foam that was re-applied to the work site.

‘Have had problems this (past) week with cold weather and moisture, but Lockheed Martin has done a great job at reworking the plan, scrubbing work content, and reorganizing the work to stay on schedule,’ noted Shuttle manager Wayne Hale on the latest Stand-up/Integration report. ‘Still on schedule for completion by end of month.’

Finding the specific root cause to the ECO (Engine Cut Off) sensor anomalies is also looking hopeful, as test runs on ET-125’s removed connector continue at the Marshall Space Flight Center (MSFC).

‘Time-Domain Reflectometry (TDR) data shows the problem is near the socket (within centimeters),’ added Hale. ‘Much of work at MSFC is supporting qualification and flight rationale.’

Large scale evaluations are also continuing into the observations of glass cracks, seen in inspection images of ET-125’s removed connector. The concern related to the potential of LH2 leaking through the cracks during ascent.

While that safety risk is no longer deemed a constraint to STS-122, a large portion of Thursday’s PRCB (Program Requirements Control Board) meeting presentations overviewed the forward plan – one which will certify the glass seal for up to 20 cyro cycles/tankings.

**Ride home through the fire, sparks and plasma of re-entry with Atlantis, Discovery and Endeavour. FIVE Stunning high quality 2hr, 355-400mb Camcorder and HUD videos – from payload bay closure – through re-entry with an astronaut held camcorder video – to post landing – several more videos showing landing from 90,000 ft also available and HUD videos from STA landings. Includes HALO II Re-entry video, and re-entry videos from Gemini and Apollo (converted from 8mm)**

ET-125, which has now been through three cryo cycles, also has a couple of cracks on its feedline brackets – as is usual for the tanks. However, they are unlikely to require any work ahead of launch.

‘On STS-122, have a couple of cracks on some ET feedline brackets from previous two tankings,’ added the Stand-up. ‘Working on risk and will bring story to Program delta FRR. Feel risk is small.’

Separate from the tank, it has still be an interesting flow for Atlantis, ahead of her mission to carry the Columbus module to the International Space Station (ISS).

An issue with the orbiter’s ATVC (Ascent Thrust Vector Control) box #2 – specific to the commanding of the Right Solid Rocket Booster (SRB) Rock Actuator – led to its removal and replacement. The removed unit has since undergone testing to find the cause of the issue.

‘ATVC box is (undergoing testing). They were able to repeat problem a number of times. Continued to troubleshoot this through thermal and vibration testing. Isolated problem to card, so removed and replaced it,’ added an engineering report.

‘Re-tested ATVC without the card, and it doesn’t exhibit problem, so confident that they now have the right card. Will begin troubleshooting card and see if can isolate problem to a component.’

The Orbiter Project Office (OPO) are also working towards accepting a small issue with Atlantis’ Pan Tilt Unit (PTU) – on the Orbiter Boom Sensor System (OBSS) package – as acceptable to fly as-is.

‘Completed additional axis of vibration testing. X-axis was last to be completed. Everything was successful, and vibration testing is now done. Stress analysis data is due tomorrow, and (OPO manager) Steve Poulos hasn’t heard any negative comments regarding this. He assumes they’re close to closing out this out for STS-122 as acceptable for flight. Will present this during Program Delta FRR.’

Meanwhile, processing continues to go well with Discovery and Endeavour, as preparations for three launches in just over a 10 week period continue.

‘Endeavour/STS-123: down to zero tile cavities. Ready to roll on February 7. Orbiter mate planned for February 12. Work on tank is critical path on installing connector,’ added processing information. ‘Discovery/STS-124: Orbiter mate is planned for March 17, and ET/SRB mate is scheduled for February 23.’

L2 members: All documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, updated live.

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