ASA and ET Cam Latest:

No additional anomalies of note have been recorded by the Mission Evaluation Room (MER) since Flight Day 2, allowing engineers to concentrate on evaluating the root cause of the Aerosurface Servo Amplifier (ASA) failure during ascent.

At present, the single channel failure of the quadruple tolerant system has no mission impact. However, a second failure would cause the mission to end – with a landing on the next available opportunity. A second ASA failure is highly unlikely.

Regardless, a Tiger Team level investigation is ongoing, with engineers looking at historical data and engineering records on the ASA system. It is normal for such investigations to be called – especially during a relatively issue-free mission – in order to utilize the large engineering community, gathered for mission support, to build a stock of additional data on the hardware, via what is known as “lessons learned”.

The other main issue of note relates to the troublesome ET Umbilical Well camera system, which appears to be a fleet-wide issue. Several efforts to download the images have failed, although 46 images of the separated tank are available to the crew, and will be assessed once Atlantis returns home.

“ET Umbilical Well Camera File Transfer (AR 3949). Camera failed to transfer imagery to ground,” noted last night’s Mission Management Team (MMT) overview presentation, available on L2. “Generated the same error message on-orbit that was observed during repeated pre-flight tests – ‘unable to transfer images from card’.

“Crew reported that there are 46 images on the camera as expected. Images can be obtained from the memory card post-flight. The team will assess available time at the end of FD2 to see if a follow-up attempt to download these images is possible to support the damage assessment process.”

In other news, the Solid Rocket Booster Retrieval Status lists that: “Dive operations were completed successfully yesterday (Tuesday). Both boosters are under tow; Liberty Star and Freedom Star are expected to dock this morning at 0800L and 1100L respectively. Open assessment is scheduled for tomorrow at 0700L.”

Meanwhile, the damage sustained by Pad 39A during Atlantis’ launch will not delay STS-127′s schedule – with Endeavour due to transfer from Pad 39B to 39A after STS-400 LON (Launch On Need) standdown, for her STS-127 mission next month.

“Post-launch pad securing operations, wash-downs, and walk-downs are proceeding as planned,” added processing information on Wednesday. “The team is continuing to evaluate pneumatic lines that were impacted by liberated Fondue Fyre. Initial reports indicate that the pneumatic lines can be replaced in less than a week and should be no issue for turnaround operations.”

Chine Damage Cleared/TPS Latest:

The images will likely confirm the current theory that the debris strike on Atlantis originated from one of the ET Ice Frost Ramps (IFRs), although this can be assessed post-mission, after it took just several hours for the DAT (Damage Assessment Team) to clear the line of TPS ‘dings’ caused by T+102 seconds (estimated) event.

UPDATE: On Wednesday afternoon, DAT images confirmed a liberation from location Xt714 on ET-130 – further information will follow via an upcoming article – 16mb DAT “full vehicle” TPS status presentation being uploaded to L2.

The damage was observed during the OBSS inspections on Flight Day 2, although at no point were members of DAT concerned with the initial observations, including it only as a note of interest in their general first look overview.

“DAT Status: Did see some indications of damage on starboard chine (21” long skip down several tiles) in FD2 inspection imagery. No issues noticed for T-0 or lower surface, but data review is in work.

“Upper Canopy Inspections Complete: No damage failing criteria was identified. Starboard T-0 inspection complete: Data review in work. Lower surface scans initiated: No obvious damages identified. Chine damage identified: 106 sec debris event. WLE (Wing Leading Edge) sensor indications.

“There were two indications from the wing leading edge sensors during ascent on the starboard chine that appear to correlate to available imagery for a noted debris event around the 106 second mark. FD2 inspections identified approximately 4 tiles in the area with dings. The tiles in this area are approximately 2.5 inches thick.”

WLE IDS:

The WLE indications came via a post Columbia modification called the WLE IDS (Wing Leading Edge Impact Detection System), a post Columbia modification that allows the orbiters to “feel” any impacts on their critical leading edge TPS via a network of embedded sensors.

The system is so sensitive, ‘ghost triggers’ can be registered throughout a mission via thermal conditions interacting with the orbiter’s hardware.

It was the WLE IDS sensors that likely ‘felt’ the debris impact on the chine area of Atlantis’ starboard WLE, the first of which was timed at T+104.3 seconds, measuring at 2.9 Grms – which is still a low reading, with only readings over 10 Grms usually deemed as the benchmark for an impact of concern.

The second was timed at T+120 seconds, measuring only 1.8 Grms, immediately adding confidence that the impacts were unlikely to be of a major concern.

“All WLE IDS ascent summary data were down linked and downloaded successfully,” noted the WLE IDS presentation to the MMT, available on L2. “Thirteen (13) half second windows of detailed G time histories were downloaded in order to confirm the implication of cases above 1 Grms. There are no reportable indications on the RCC. However, two (2) indications were identified on the starboard chine area.

“Overall, STS-125 background levels are very similar to background levels of previous missions. No data anomalies have been identified. All units triggered on Main Engine Ignition within 0.15 seconds of each other.”

Tyvek Covers:

The only other item of interest via ascent imagery related to a couple of late releasing Tyvek Covers – used to protect the Reaction Control Systems (RCS) thrusters from water and debris intrusion during the pad flow. This is also not an unusual issue, and is only noted as late releases have a small amount of potential to become debris hazards at high velocity.

The covers are designed to liberate from the vehicle within seconds of launch, however, during STS-125′s launch, a small piece of cover remained attached to the F4D thruster, before liberating later in ascent. It failed to impact the orbiter.

“Ground imagery reported that when thrusters F3D’s and F4D’s Tyvek rain covers released at 131/18:02:03.9 (00/00:00:07.9 MET) at ~150 ft/sec (~102 mph) and 131/18:02:4.4 (00/00:00:08.4 sec MET) at ~160 ft/sec (~109 mph), respectively, a piece remained attached to each thruster lip,” noted a report on a MER presentation to the MMT.

“The F3D piece separated at 131/18:02:15.2 GMT (00/00:00:19.2 MET) at ~413 ft/sec (~282 mph). The F4D piece separated at 131/18:02:15.8 (00/00:00:19.8 MET at ~428 ft/sec (~292 mph).

“The estimated size of each piece is ~2 grams, which within accepted limits. Imagery indicates that the pieces that released late did not impact the Orbiter.”

Flight Day 3 (FD3) Overview (refer to live updates for up to the second coverage):

During what will be an historic day for the space program, Atlantis will mark the final time an orbiter will rendezvous with the Hubble Space Telescope.

The Flight Day will consist of the rendezvous, HST’s Solar Arrays positioned for grapple by Atlantis’ RMS, HST grapple and berth on Flight Support System (FSS), the Shuttle Robotic Arm survey of HST, and an EVA 1 procedure review.

Pre-empting her arrival, the Space Telescope Operations Control Center (STOCC) at Goddard are finalizing their preparations of the Telescope for the start of its re-servicing.

“Ground Commanding: The STOCC performs several steps to prepare HST for rendezvous and berthing with the orbiter,” noted FD2 to FD3 outlines on the Flight Plan Walkthrough (L2).

“Highlights for FD2 through FN2 include dumping of onboard Solid State Recorders (SSR), closure of the aperture door (AD), maneuvering HST to the rendezvous attitude, reconfiguration of the comm. system from High Gain Antenna (HGA) to the Low Gain Antenna (LGA) direct TDRS, reconfig of three gyro operations, load shedding activity, and HGA deactivation retraction (to maximize clearance for HST grapple).

“The STOCC maneuvers HST to a rendezvous attitude designed to maintain HST power and minimize plume loading on the solar arrays (SA’s) at the 1500 foot normal Z braking gate.

“This attitude is determined by the conditions as follows: Sun in the V1-V3 plane and +V1 pointing down the R-bar at an orbit angle of 59 deg before orbital noon.

“The STOCC slews the solar arrays to 90 degrees, to provide clearance with RMS. The orbiter approaches HST using an R-bar approach to minimize prop usage and potential contamination.”

The orbital ballet between Atlantis and Hubble will see the orbiter approach HST from below, rising up the R-bar, ahead of capturing Hubble via the Shuttle RMS.

“Before the orbiter is within 200 feet of HST, HST performs a roll maneuver to the capture attitude to align the +V2 grapple fixture on HST with the RMS. The roll mnvr will place the -V3 52 degrees out of plane north as measured on the anti-Sun side of HST.

“The magnitude of the roll mnvr is ~ V1 = Beta – 52 degrees, resulting in a roll that ranges from 0 deg to -104 degrees. Orbiter then performs an inertial approach.

“HST Approach & RMS Capture/Berth Operations: The RMS is used for grappling and berthing the HST in the orbiter payload bay. Grapple is timed for sunset + 5 minutes. RMS HST maneuvering is done with Orbiter in freedrift.”

Hubble will then be secured on the FSS at the aft of the Payload Bay, latched into place for an imagery survey of the telescope, ahead of the of the EVA work that will result in Hubble’s life span being extended well into the next decade.

“HST Configuration at Berth: Orientation: -V3 Forward. Solar Array Position: 90 deg. External Power Activation (Crew & STOCC) – After umbilicals connected at the end of the Berth (Latch & Mate procedure), FSS Power Control Units (PCU’s) , external main power and external essential power are applied.

“Photo/TV05 Survey (-V3) via RMS and P/TV. Battery Charging – one full daylight pass. Solar Array Slew to 0 degrees in preparation for EVA 1 on FD4. Array’s are slewed after completion of battery charging and maneuver to overnight attitude (–ZLV –XVV).”

EVA-1 will begin on Flight Day 4, conducted by John Grunsfeld and Andrew Feustel – the first of five planned spacewalks during STS-125. Preparations have already begun for the opening EVA.

“Airlock Prep was completed followed by checkout of EMUs 3015 & 3017 starting at 13:37 GMT (Tuesday). All suit data was nominal & battery recharge of s/n 2080 & 2070 was completed. EMUs were then swapped out & checkout of EMUs 3008 & 3004 began at 16:39 GMT. All suit data was nominal & battery recharge of s/n 2081 & 2082 was completed,” noted a status report.

“As expected, the BATT V DECAY message was received after FAN start up on the 3 EMUs with new ICBs installed (s/n 2080-2082). The battery team has observed this signature for the new ICBs during initial cycles & determined this to be nominal.

“Cabin has been depressed to 10.4 PSI in preparation for the upcoming EVAs.”

More will follow throughout Flight Day 3.

L2 members: Documentation – from which most of the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

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Atlantis rolled over to the VAB on Monday, after a slight delay caused by unacceptable rollover weather. First motion out of OPF-1 (Orbiter Processing Facility) occurred at 11:30 local, with the orbiter spotted in the transfer aisle at 12:23.

Once in the VAB, Atlantis underwent S0004 (Orbiter/ET Mate) operations, which saw the Aft and Fwd Sling mate to the orbiter completed at 18:41 on Monday. Atlantis was lifted to the vertical at 2235, and being positioned in High Bay 3 for mating.

“Orbiter/ET soft-mate was completed at 19:42 local on Tuesday,” noted processing information on L2. “Orbiter/ET hard-mate was completed at 2141 last night. Sling has been removed and in the transfer aisle ready for disassembly.”

Completion of the mating operations – which is based around mating and torquing of the LH2 and LOX umbilicals on the aft of the vehicle – was delayed when a socket was accidentally dropped from near the top of the vehicle, before bouncing off the ET cross beam, impacting a tile in the umbilical area.

“During final torque of the forward bipod fitting to flight value, the socket from the torque wrench was dislodged and fell. Damage to flight hardware has been assessed as follows: ET box beam damage is minor and can be repaired in place,” added L2 processing information.

“Orbiter tile damage on the aft belly. The area is 1.25 inch x 1.25 inch and 0.25 inch deep. Engineering is evaluating of repair methods.”

Thankfully, the damage is not in the nearby ET Door edge tile area of the orbiter belly, which would have likely required demate and rollback of Atlantis to the OPF for a repair. Because the area is repairable in the VAB, the completion of LH2 and LO2 umbilical stud tensioning was approved, and occurred at 3am on Wednesday morning.

Engineers evaluated a putty repair on the damaged area. However, accessing the damage was deemed problematic, due to its location being behind the structural cross beam – making access and application of the heat lamps much more difficult.

However, the putty repair plan was approved, leading to the application work being carried out overnight, which is now ‘setting’ under the heat lamps. Rollout to Pad 39A at the end of the month will remain on schedule.

Other processing work taking place for Atlantis’ NET (No Earlier Than) May 12 launch includes the White Room at Pad 39A being extended for access to the Crew Module. Crew hatch functional work is also complete. The S0008 (Shuttle Interface Test) call to stations is planned for 1700 local on Thursday.

The Tail Service Mast (TSM) electrical mates are also complete, as the flow continues to work toward rollout of STS-125 to Pad 39A on Tuesday, March 31 – with first motion planned at 0001 EDT.

A simulation of the countdown and launch – part of S0044 operations – also took place this week in Firing Control 4 (FR4) at KSC this week, which tests controllers on their reactions to several problems the firing room system programs and project guys throw at them.

During the STS-125 simulation, more than four major issues were simulated, including an abort after SSME (Space Shuttle Main Engine) start on the second simulation. Controllers were also tasked with dealing with SSME 1 failing to shut down as commanded by the abort, which was ably dealt with during the simulation.

Meanwhile, good news has been noted on the replacement hardware that Atlantis will carry to Hubble – which will replace the Science Instrument Command and Data Handler (SIC&DH) Side-A that failed back in September.

The replacement SIC&DH has completed an exhaustive test program, with positive results ahead of being shipped to KSC where it will become part of STS-125′s payload.

A recent scare had been noted, relating to a major subsystem that was deemed to have failed. However, this was traced back to a misbehaving VAX computer on the test suite.

L2 members: Documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

Related posts:

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STS-125 has been delayed several times from its October launch date, following the failure of the Control Unit/Science Data Formatter (CU/SDF) Side A.

Engineers on the ground managed to bring Hubble back to full operational capability via a switching of the CU/SDF to its Side B in mid October, with the challenge subsequently moving towards the timely shipping of the replacement hardware to the Kennedy Space Center (KSC).

That replacement hardware, which suffered from anomalous readings during checkout, is still undergoing testing, although the current launch date projection is still tracking May 12, 09.

The May launch date will not be classed as solid until the replacement hardware is officially deemed as good to fly, which is not the case at present. However, HST program manager Preston Burch remains confident.

“We are on track for a launch in mid May 2009. We held a successful Pre-Environmental Readiness Review (PERR) on December 16,” noted Burch on Wednesday to WLNS TV6, before adding that they are yet to find a root cause of the anomalies.

“Extensive testing and inspection of the CU/SDF-A failed to reveal a ‘smoking gun’ – therefore, we are moving on to the environmental test program (EMI/EMC, vibration, and thermal vacuum testing) in mid December per our plan. We still have a good amount of schedule slack at this point to deal with problems which could arise.”

Mr Burch also noted that the replacement hardware was suffering from “tin whiskers” – an issue that the shuttle program is no stranger to, as this was the catalyst for a level of engineering dissent from the Aerospace Corporation, ahead of STS-121.

That dissent was dismissed by NASA, following their own investigation that showed there was little chance/risk that the small slices of metal – otherwise known as “tin whiskers’ – could liberate on to the circuit boards – which in turn could cause shorts in the orbiter’s electrical components, which held the potential of a LOV/C (Loss Of Vehicle/Crew) event.

With regard to the replacement PCU, this issue – which was expected to be found – has been corrected by HST engineers.

“Inspection of the Power Control Unit revealed tin whiskers and tin nodules, which were remediated,” added Mr Burch. “This was pretty much what we expected based on the early in-flight anomaly when we switched to the B-side, and its shut down (it subsequently was restarted with no problems, and has been rock steady since).

“The flight spare CU/SDF-B was also opened and inspected. Workmanship on all of the flight spare hardware is rated as very good, with no issues. My expectation is that we will have no problem certifying the flight spare for SM4 (STS-125).”

The next meeting by the Space Shuttle Program (SSP) is expected around January 8, likely taking place at the first Program Requirements Control Board (PRCB) meeting of 2009. By then, Hubble engineers are likely to have completed their testing of the replacement hardware, ahead of providing a status report to the SSP.

Options available to shuttle managers range from added confidence that May is viable for STS-125, that the updated timeline rules out May – which would lead to a delay to November, or to meet again later that month.

Should the mission slip at the upcoming meeting, L2 notes – which reference as switch to November – point to STS-127 with Endeavour taking up the May launch slot, with the Atlantis/STS-125 stack moving from High Bay 3 (HB3) to HB2 sometime in January, in order to permit the MLP (Mobile Launch Platform) that will be used for Ares I-X to be moved into HB3. That would allow Ares I-X to get off the ground before the end of July.

Ares I-X remains on track for July, but only if certain SSP arrangements are made, notably on STS-400′s use of Pad 39B.

Evaluations are taking place into the possibility to utilize a previously scrapped plan to use Pad 39A for STS-125 and – via a record turnaround of the pad – the STS-400 (Endeavour) LON (Launch On Need) shuttle. This would involve Endeavour arriving at Pad 39A just days after Atlantis had departed.

A decision date of January 23 has been set, although a positive outcome on using Pad 39A for both vehicles remains challenging due to the broad dismissal of that option when it was first proposed (presentation on L2).

Should manages decide to keep to the current plan, which would mirror the dual pad use by Atlantis and Endeavour earlier this year, ahead of the postponement of STS-125, Ares I-X is likely to be delayed until October – due to the delay in modification work on Pad 39B from shuttle ops, to Ares I-X ops.

Those decisions can wait until next month, with Mission Management Team (MMT) chair Leroy Cain stating that the teams should look forward to spending the Christmas holiday relaxing with their families, in order to be fresh ahead of an extremely busy 2009.

“This will probably be the last week of being here and doing work in earnest for 2008. We are trying not to have most of our regularly scheduled meetings for the week of December 22 and the week following,” noted Mr Cain on the latest Shuttle Stand-up/Integration report on L2.

“Will have meetings if required, to do critical path work and things of that nature. The intent is to work hard this week and get folks out of here and take as much time off as possible to spend with family and get some down time during the holidays.

“There is a big calendar year coming up, so we’ll finish this one up in fine fashion. Get all your work done this week if possible.”

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HST engineers started transmitting lines of complex programming to the aging telescope on Wednesday, which included one final attempt to bring Side A to life.

Engineers are back in contact with Side A, and are utilizing data to gain diagnostic information from the Control Unit/Science Data Formatter (CU/SDF) hardware.

Transition to Side B has been issue-free, with engineers receiving telemetry that verified they had good data. Hubble’s 486 computer was reloaded with data and successfully performed a data dump back to the ground to verify all the loads were proper.

Hubble was then brought out of safe mode and the 486 computer was placed back in control. Engineers have reconfigured Side B’s computers to execute pre-science command loads and resume communications satellite tracking with the HST high gain antennas.

It was expected to take until Friday to complete the task of swapping over to Side B. However, the process was completed in just over 20 hours.

Everything seemed to be going as hoped until Friday, when two anomalies were observed during the activation of HSTs’ science instruments, and the resumption of science observations – which have now been suspended.

The first event occurred at approximately 1:40 PM on Thursday when the Advanced Camera for Surveys (ACS) suspended operations due to indication that one power source in the Solar Blind Camera’s low voltage power supply failed to turn on.

This was the first turn on of the Solar Blind Camera since its last use prior to the safing of HST’s NASA Standard Spacecraft Computer, version 1 (NSSC-1) on September 27.

The first step taken in investigating the NSSC-1 safing was to collect a memory dump. This dump was success. The data shows that yesterday’s anomaly is likely different from the one that occurred on Sept. 27.

Initial indications point to a potential problem in the B-side of the Computer Processing Module (CPM-B). The CPM-B had not been used on orbit prior to Wednesday evening’s activation of Side B of the Science Instrument Control & Data Handling (SIC&DH) unit.

The spacecraft computer is continuing to execute command loads sent to it from the Space Telescope Operations Control Center (STOCC) at GSFC, and all of its subsystems are nominal. The investigation is continuing.

Hubble’s replacement hardware – which will hand the telescope a new Side A and Side B – is the key driver to STS-125′s launch date, which is currently tracking February 17 NET (No Earlier Than).

HST managers have noted that the hardware needs to undergo several months of pre-flight checkouts, including vibration testing, before being shipped to the Kennedy Space Center (KSC) for integration into Atlantis’ payload.

Should the timeline prove to be too restrictive on the February launch target, Discovery – on STS-119 – would return to the previously allocated widow, with Atlantis moving to April/May. This is mainly related to the need to have a LON (Launch On Need) shuttle “dual processed” for STS-125′s rescue requirements.

“Manifest Options: The Hubble Space Telescope team continues to evaluate their schedule for delivery of requalified spare hardware for launch on STS-125 to recover science operations,” noted Tuesday’s 8th Floor News (HQ memo).

“The expectation is that they will have a better understanding of their schedules in early November, which will factor into the decision on whether STS-125/HST or STS-119/15A launches in February.”

When the decision will be taken is believed to be November 5, according to STS-125 Mission Director Chuck Shaw. However, this all depends on the status of Hubble and its delivery timelines associated with the replacement hardware.

“The first pinch point in trying to protect STS-125/HST, STS-119/15A, and STS-401/OV103 HST LON all in February is flight software products, currently driving a late October decision date,” added the memo.

“However, depending on the results of the Flight Design assessment of the STS-401 template, it may be possible to delay the decision to mid-November, which syncs well with Hubble’s decision timeline.

“Bottomline is that folks are working all angles to ensure manifest decisions are made with the best data possible. So stay tuned, we’ll know more in a few weeks.”

STS-125′s payload has finally been removed from Pad 39A’s PCR (Payload Changeout Room), following a delay due to poor weather in the local area. This will free Atlantis for rollback on the 20th.

“The HST Payload canister was lowered last night and transferred to the PHSF (Payload Hazardous Servicing Facility) today,” noted processing information.

“Integrated preps for rollback are scheduled to begin today. RSS (Rotating Service Structure) move to park is scheduled for 1st shift Sunday, and 1st motion for rollback is scheduled for 0000 hours Monday.”

An issue with Atlantis is also being worked at the pad, which relates to a MDM (Multiplexer/Demultiplexer) card – the same hardware that caused a split of the GPCs (General Purpose Computers) on Discovery during pre-launch preparations ahead of STS-124.

“Documenting MDM OA2 reporting a Wrap failure. The team conducted troubleshooting again yesterday to try to isolate the condition,” added processing information. “MDM OA2 is still failed. MDM failed immediately upon power application to main busses.

“PCMMU (Pulse Code Modulation Master Unit) switched from 2 to 1 after power up. All MDM wraps are good in PCMMU 1.”

No issues have been reported with Atlantis’ GPCs – which read data and send commands to the MDMs – with the card likely to be changed-out either before rollback, or once back inside the Vehicle Assembly Building (VAB).

Related posts:

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Hubble troubleshooting is proceeding well, with NASA engineers preparing to switch over from the Side A control system, to the back-up Side B.

Those preparations are on track, with the Science Data Formatter (SDF) on Side A of the Science Instrument Command and Data Handler (SIC&DH) “recovered” to the point that the hardware has been confirmed as a hard failure.

Last week’s recovery is, however, providing additional insight into the SIC&DH condition, as well as providing additional monitoring of the science payload.

Atlantis/STS-125 Latest:

Atlantis’ mission to service Hubble has now moved to the right by five days on the projected launch date, which continues to track February.

This latest refinement was confirmed by STS-125 Mission Director Chuck Shaw, with the current target also continuing to point towards Discovery acting as the LON (Launch On Need) vehicle STS-401.

“At the SSP/ISS (Space Shuttle Program/International Space Station) scheduling meeting, it was agreed to by the SSP Manager to aim STS-125 at 2/17 for a ‘work to’ date, rather than simply stating ‘Mid-Feb’,” noted the memo.

“Earlier, the scheduling community had asked for 2/12 to be looked at, but that is somewhat OBE (Overtaken By Events) now. That will also then aim STS-401 at 2/24 (HST+7).”

A scheduling meeting will take place on November 5 to confirm the refined launch date targets, which are now focusing on two opportunities, the latter an alternative launch date – in May – based on the potential of problematic scheduling issues with the February target.

“Evidently, the senior managers within SOMD (Space Operations Mission Directorate) and SMD (Science Mission Directorate) have agreed that a decision will be made on Nov 5th for pressing on towards the Feb opportunity or a later one (May).

“Not sure when a manifest CR will be put into coordination, since it appears that everyone is able to keep moving forward based on the ‘work to’ date while the HST troops come to grips with getting the telescope switched over to the B side and also assess the status of the replacement avionics.”

The removal of the HST payload from Atlantis has been proceeding throughout the weekend, with the canister set to depart from Pad 39A on Monday. Work will then take place to prepare Atlantis for her rollback to the Vehicle Assembly Building (VAB).

“Are on target to move vehicle from Pad A to VAB High Bay 3 on October 20,” noted United Space Alliance Ground Operations on L2. “Payload Canister hoisting and Payload Ground Handling Mechanism positioning to Wings and Ladders in support of HST Payload transition into the canister on Monday.”

Endeavour/STS-126 Latest:

Atlantis departure will be followed by the transition of Endeavour from Pad 39B to 39A, follow her stand-down from STS-400 requirements.

Now tracking a November 14 launch for her primary STS-126 mission, an October 25 arrival at 39A will have built-in flexibility for that launch date.

“On Pad B, are continuing preparations for moving OV-105 to Pad A on October 25, 2008,” added Ground Operations. “When get to Pad A, will have four contingency days for launch on November 14, 2008.”

STS-126 is currently undergoing a series of Flight Readiness Review (FRR) departmental runs, following last week’s milestone MOD FRR (17 presentations on L2). No major issues are currently being reported in the run up to the SSP FRR.

“The STS-126 Payload Readiness Review was held at KSC,” noted one example on L2. “Have open paper, mainly concerning ECLSS (Environmental Control and Life Support System) issues for the six man crew. Most of this paper will still be open when the vehicle rolls to Pad 39A.”

This payload review has been aided by the latest analysis on the “Leonardo” Multi-Purpose Logistics Module (MPLM), via a Verification Loads Assessment (VLA) – which was initiated by an ability to add additional payload to the module.

“MPLM weight for the racks showed that five racks are out of tolerance for weight/C.G (Center of Gravity),” added Flight Operations and Integration. “This issue is being worked, but we have plenty of margin. Additionally, are now expecting racks to return lighter than expected compared to original VLA studies.”

Discovery/Dual LON/STS-119 Latest:

Overall, Discovery is the main factor via what is now a dual LON requirement, which opens with supporting Endeavour’s mission by being ready to launch on a rescue early next year.

The two main issues relate to the timely delivery of External Tank ET-130 from the Michoud Assembly Facility (MAF), and the delivery of a new RCC (Reinforced Carbon Carbon) panel (10R).

“ET-130: Processing is nominal. ET-130 is in final assembly position 3. Are working TPS (Thermal Protection System) preparations for nose cone installation,” noted Lockheed Martin/MAF on L2.

“The tank will be moved to Bldg 420 on about October 15. Trying to allow moving tank completion date in from November 21,” which would be within the required schedule.

Lockheed Martin are also pushing forward their delivery date of 10R, although engineers at the Kennedy Space Center (KSC) are looking into the back-up plan of a donated panel, one that has previously flown with Atlantis and Endeavour.

Due to the unique ‘fit’ of these panels, which are mainly orbiter specific, fit checks have been carried out on these ‘spare’ panels all last week, with the results expected in the next few days, as normal processing continues.

“RCC fit checks on the OV-104 and OV-105 panels are complete,” added processing information. “SSME (Space Shuttle Main Engines) electrical connector mates were rescheduled for Monday. The team continues to work preps associated with ET Door Functional; scheduled for Monday.”

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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While plans are now solidifying for the short term, evaluations are continuing on whether Atlantis will need to be de-stacked over the New Year.

As previously reported, this weekend will kick-off operations to remove Atlantis’ Hubble servicing payload, before a large quantity of her hypergolics will be offloaded prior to rollback to the Vehicle Assembly Building (VAB) on either October 19 or 20.

“Will pick up this weekend with payload de-mates. Will get the payload to the canister around October 13. Once that is completed, will go into fuel offload,” noted KSC Ground Operations. “Target is to move STS-125 stack from Pad A to High Bay 3 around October 20.”

While they are subject to refinement, preliminary orbiter specific and integrated schedules – available to download on L2 – have been created for the upcoming processing milestones, which focus initially on Atlantis’ eventual move back to the VAB.

Should those milestones remain unchanged, the HST payload will be removed from Atlantis next Tuesday (October 7), with the Rotating Service Structure (RSS) retracted to its parked position on Friday (October 10).

The payload canister containing the HST servicing hardware will then be lowered from the pad the following Monday (October 13), before the RSS is moved back to the mate position later that day, in preparation for the offloading of the hypergolics from the OMS tanks – scheduled for the end of that week (by October 17).

Preparations for rollback to the VAB are tracking RSS retract on Saturday evening (October 18), ahead of first motion off the pad at 4am Sunday (October 19) – although this date is likely to be a NET (No Earlier Than) – given October 20 remains pencilled in for the trip back to the VAB.

Still under evaluation for Atlantis is whether she’ll need to be de-stacked and sent back to her Orbiter Processing Facility (OPF). A list of issues relating to staying stacked in the vertical for a few months inside the VAB are being balanced against the benefits of sending the orbiter back to the home comforts of the OPF.

Some required operations can take place whilst inside the VAB, such as the potential changeout of the range safety batteries on the Solid Rocket Boosters (SRBs) and ET cameras. However, structure engineers are continuing evaluations on ensuring Atlantis’ Payload Bay doors won’t soak up too much moisture – which would be aided by the environmentally controlled OPF.

Other factors include the possibility Wing Leading Edge (WLE) inspections may be required, along with Main Landing Gear (MLG) door seal compression measurements and tire pressures – the latter currently certified for a landing as late as April 15, 2009.

“The one issue that we couldn’t quite close out is the MLG door pressure seal,” noted the Orbiter Project on the latest Shuttle Stand-up/Integration report (L2).

“Had good rationale if we had flown this month, but given that it will be down some number of months and the seal is going to stay in compressed state longer, that requires a little more work. Are off doing that, and we will have further discussion before we fly.”

Atlantis may also require her General Purpose Computer (GPC) and GPS batteries changing out – the latter certified only until January 20. The Modular Auxiliary Data (MAD) System and Microwave Scan Beam Landing System (MSBLS) magnetron also require testing, among other items.

“Relative to time and lifecycle requirements, the two that we must look at include the WLE corrosion exception,” added the Orbiter Project.

“Though we wrote exception to say ‘out of OPF by October 31′, we will make sure we are good there, given that we will be sitting out at pad and VAB a little longer.

“The team also identified Window Contamination Control System (WCCS) conditioning valves that time-out around March 11. That is the one we will have to work on a little bit more.

“Looking at the various manifest options, and what time and cycle requirements might come due depending on how the launch sequence plays out. Also looking at any analyses that must be redone, or done for the first time because the order of flights has changed.”

Endeavour/STS-126 Latest:

Over on Pad 39B, Endeavour – now stood down from her STS-400 role – is patiently waiting for Atlantis to vacate Pad 39A. Operations are closing in on the completion of hypergolic loading on Endeavour, which will cut down on the amount of processing time once she swaps pads.

“S0024, Hyper Propellant Load: SCAPE operations at Pad B resumed Thursday morning at 0700 EDT. Right OMS/Left OMS Oxidizer load is complete. Left RCS (Reaction Control System)/Right RCS Ox load is complete. FRCS (Forward Reaction Control System) Ox load is complete,” noted end of week processing information on L2.

“The pad was opened for controlled work at 0451 hours Friday to repair an FSS (Fixed Service Structure) elevator and one comm box. Fuel loading operations for the FRCS, APS, and APU’s are scheduled to begin at 0600 Friday morning and continue through 2nd shift tonight.

“Weekend work: S0024 completion activities on Saturday if required. We’ll then be waiting to roll the STS-126 stack off of Pad B and over to Pad A. That will happen on October 25.”

Expanded milestone charts – again preliminary – show STS-126′s “Leonardo” Multi-Purpose Logistics Module (MPLM) payload is due to arrive at 39A on October 23, just prior to Endeavour’s mini-rollout from 39B.

The November 14 NET (No Earlier Than) launch date – as previously reported and now classed as official – remains fluid, with the smooth operation between removing Atlantis from 39A, and the timely arrival of Endeavour, part of the key milestones, along with the added factor of “crew loading” – which remains on a tight timeline.

Flight Readiness Review (FRR) meetings also need to be conducted, where all relevant departments will discuss their status ahead of launch. So far, no departments have raised any major concerns with the November 14 NET.

“Working assessments related to the launch date change for STS-126,” noted EVA as one example. “Don’t see any significant pokeouts.

“Waiting for additional input next week. The bigger impact will be the number of suits in flow. There were some limited life components with the suits scheduled to fly on STS-125 that will require some additional maintenance.”

A special STS-126 L2 Section is now live, with several expansive mission baseline presentations, PRCB (Program Requirements Control Board) presentations and live USA/NASA/NTD processing reports available in the run up to Flight Data File and Flight Readiness Review (FRR) coverage.

Hubble Status:

Engineers are closing in on next Wednesday for the switchover from Side A to Side B of Hubble’s SIC&DH (Science Instrument Command and Data Handling) system.

Due to the complexity of the operation, engineers carried out a “dry run” on paper of procedures on Friday.
“HST team is moving forward with plans to take telescope to side B. Campbell independent review (gave) a “go” to dry-run this activity on VEST (their version of SAIL – Shuttle Avionics Integration Lab),” noted Flight Operations and Integration.

“On Monday, HST will brief results and plans to Goddard Center Director. Tuesday, HST will take it to HQ. Wednesday, plan is to have them press on with commanding over to side B. When complete VEST work to take the side B routine over, will start flight qualification work on the new SICBH boxes.”

The results of Wednesday’s switchover will play a major role in the requirements Atlantis will be tasked with, when she eventually launches to service Hubble, next February or April.

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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October 20 has been pencilled in for Atlantis’ rollback from Pad 39A, which will clear the pad for hosting Endeavour.

Processing at the pad has ceased on the orbiter and her stack, which was heading into a series of closeouts for launch, until the mission was postponed to 2009.

“S0600: Battery charge was initiated on Saturday and continues. Vortex cooling is performing nominally. Payload Interface Verification Test: Interface verification tests are complete. Payload end-to-end test picks up today,” noted processing information on Thursday.

“Program has approved removal of HST payload, that work is scheduled to begin this weekend. Orbiter aft closeouts and aft confidence tests remain on hold.”

Whether Atlantis will take up residence in the VAB over the new year, or be de-stacked and rolled back to her Orbiter Processing Facility (OPF), is also evaluation.

The STS-125 stack should be ok to stay inside the VAB for several months, although the giant building does not have the orbiter comforts of the Payload Changeout Room (PCR) at the pad, or the environmentally controlled conditions of the OPF.

Factors playing a role in the decision between staying in the VAB, or de-stacking, include some concerns surrounding the observation of moisture on the orbiter’s Payload Bay Doors (PLBDs). This situation would be best mitigated by sending Atlantis back to her OPF.

Structure engineers are evaluating if the PLBDs won’t suffer any worsening in their condition by remaining stacked to the External Tank (ET-127) inside the VAB for several months.

In order to aid available options, engineers are now likely to offload Atlantis’ OMS tanks of hypergolics before rollback to the VAB.

While this is not required for a stay in the VAB, it would be required ahead of a de-stack and rollover to the OPF. This is due to Atlantis currently holding 31,000 pounds of hypers onboard her OMS and RCS (Reaction Control Systems) tanks.

Hypergolics are extremely hazardous and explosive, with the deservicing of such a large amount of hypers from Atlantis in the OPF requiring a large area of the surrounding buildings to be evacuated. Staying in the VAB would allow for Atlantis to avoid such a deservicing effort.

This particular evaluation is the likely reason managers are taking their time in finalizing a rollback plan, and what is best for Atlantis during her wait for a new STS-125 launch date.

Hubble Troubleshooting Latest:

Troubleshooting with Hubble is continuing, as engineers carry out the complex task of switching the telescope over from the SIC&DH (Science Instrument Command and Data Handling) system Side A to its redundant Side B.

This system – which provides the primary data link for commands down to the instruments and data back to the spacecraft – performs a self-check through its various subsystems. That test failed at the weekend, resulting in the SIC&DH terminating its “heartbeat signal” that is monitored by the 486 main spacecraft computer.

Upon the loss of the signal from the SIC&DH, the 486 assumed that it was not reliably carrying out its role of monitoring the health of the science instruments, and took the protective measure of issuing a global command to put all of the instruments and the SIC&DH into a minimally operating safe condition (safe mode).

The SIC&DH has two equivalent sets of electronics that provide full redundancy of all capabilities, called Side A and Side B. Side A has been exclusively used since Hubble’s launch via Discovery in 1990. Side B has been kept in reserve and is now being readied for use.

The process of switching over to Side B is a major undertaking due to the vast suite of equipment involved. Due diligence in carrying out the switchover is paramount, with the effort currently on track for next week.

The engineers are also utilizing a failure review team to gain all of the information that is available from diagnostics checks, before leaving Side A.

Atlantis will now be tasked with replacing both SIC&DH Side A and Side B during her mission – currently expected in February of next year – with the replacement unit containing both new Sides A and B – as they are contained within the same assembly that will ride uphill during STS-125.

Current evaluations for the re-aligned STS-125 mission are focusing on the unit’s location in the Payload Bay (PLB), when it arrives at KSC in January.

“STS-125 launch preparations remain on hold for evaluations of the HST command and data handling LRU (Line Replacement Unit). The Hubble team is in the process of switching over control from the A side to the B side,” noted a status report. “The outcome of the switch-over will provide additional data in determining the plan going forward.

“There is a spare LRU available that is flight certified and this unit will be bench tested and delivered to the cape in early January. Assessments are underway on what payload bay carrier location is best to install this spare LRU for flight. Several options for rescheduling STS-125’s launch date continue to be evaluated.”

Currently favored – pending Hubble requirements – is for Atlantis to launch in what was previously STS-119′s launch window in February. This would see Discovery take up the LON (Launch On Need) role on Pad 39B as STS-401 – a change from STS-400 designation, which is specific to Endeavour as the LON vehicle.

Discovery herself would then move to Pad 39A to take up her primary STS-119 role, for a launch in March.

Endeavour/STS-126 Latest:

That current plan for the first two launches of 2009 – which is still not official due to continued evaluations with Hubble – will lead to a realignment of next year’s mission schedule, although what is near-certain is Endeavour’s STS-126 being the next launch out of the Kennedy Space Center (KSC), in a window that is expected to open on November 14.

Endeavour’s roll to Pad 39A – a mini-rollout from Pad 39B – was on track for two weeks time, though this will be slightly later, with Atlantis not departing the pad until October 20. These timelines are still open for changes.

“Current planning for STS-126, based on a delay of STS-125, shows a potential target launch date of NET November 14, taking into account the current status of crew training,” noted Thursday processing information. “Options for rolling STS-126 to Pad A and associated vehicle system configurations are under evaluation.

“S0024 scape operations at Pad B resume this morning. The plan is to perform propellant loading to support the STS-126 mission requirements instead of STS-400 because of the delay of STS-125.”

Thankfully no issues are being worked with Endeavour, as she prepares to change call signs from STS-400 to STS-126. A small issue with ET-129′s LOX tank pressure was found to be the result of an open valve, with the IPR (Interim Problem Report) likely to be closed later this week.

“Low ET LOX tank pressure: Taken while performing T1002 ET pressure monitoring. The LOX tank was reading 4.2 psig. LOX engineering powered up GSE and obtained a reading of 4.3 psig,” added processing information.

“OMRSD (Operations Maintenance Requirements Specifications Document) indicates the tank can go as low as 0 psig as long as winds do not exceed 60mph. Troubleshooting found an open vent valve that should have been closed. The valve was closed and the tank was repressurized to 7.0 psig. LOX engineering will continue to monitor pressure.”

A special STS-126 L2 Section will be live this weekend, with several expansive mission baseline presentations, PRCB (Program Requirements Control Board) presentations and live USA/NASA/NTD processing reports available in the run up to Flight Data File and Flight Readiness Review (FRR) coverage.

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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While the status of STS-125′s Hubble Servicing Mission remains fluid, managers at the Kennedy Space Center (KSC) are creating plans to move Endeavour and her stack to Pad 39A in around two weeks time.

This plan would result in Endeavour launching as STS-126 for the final mission of the year, around November 14.

Hubble Fallout – STS-126 Gaining Focus:

Endeavour’s role as the STS-400 LON (Launch On Need) shuttle means she will need to be rolled off Pad 39B, for rare trip midway down the crawlerway, before being placed on Pad 39A for her primary STS-126 mission.

This will be pre-empted by STS-125/Atlantis being rolled back to the Vehicle Assembly Building (VAB) for the interim period.

There Atlantis would remain until the status of Hubble becomes clearer, with the potential to launch in STS-119′s February launch window. This would result in Discovery taking up the STS-400 – which may be re-named – role on Pad 39B, ahead of her eventual move to Pad 39A for an April mission to the International Space Station (ISS).

Another option is based around a worst case scenario with Hubble’s health, which would move STS-125 to April, launching after STS-119 in February, with Endeavour taking up the STS-400 role after post flight processing from STS-126.

The problem with Hubble relates to what is currently believed to be a hard fail of the Control Unit/Science Data Formatter (CU/SDF), part of the Science Instrument Command and Data Handling system “Side A”. Efforts are continuing to switch operations to the redundant “Side B”.

On the ground, a replacement unit is bring prepared, though it will take at least a month just to check the device and add the replacement to the STS-125 flight plan.

“There is a ground unit that can possibly be used, as it was developed for flight, but they have to have 30-45 days to check it out and have to revise the EVAs,” added notes on numerous memos on the forward plan.

At the Kennedy Space Center (KSC), Hypergolic loading of the Reaction Control Systems (RCS) was halted while pad processing with Endeavour waited for instructions from shuttle managers.

“S0024, Hyper Propellant Load: The remaining hyper load operations are on hold until the impact of HST on orbit problems are determined,” noted processing information this week, before a clearer “current approach” was forthcoming late on Tuesday.

This plan is based on rolling back Atlantis to the VAB in less than two weeks time, before rolling Endeavour off Pad 39B, to the fork in the crawlerway, then forward to Pad 39A for what will be a November 14 – or there about - launch date.

“Due to the Hubble mission problems we will delay collecting the Delta CoFRs (Certification of Flight Readiness) for STS-126,” noted another memo. “If STS-125 is rolled back to the VAB then STS-126 will stick to mostly the same timeline we are on now to launch on November 14th instead of November 16th.

“We are presently planning to pick up again with S0024 operation on Thursday morning to load hypers to the STS-126 load instead of previously planned STS-400 load and then plan to roll to Pad A in about two weeks.”

Endeavour can be rolled from pad to pad with a full load of hypergolics without issue. The only requirement to offload would be if she was demated and rolled back into her Orbiter Processing Facility (OPF).

One key driver to launching Endeavour as early as possible for STS-126 relates to the crew – known as “Crew Loading”. However, this is now being aided by an improved timeline, as all relevant centers do their bit to help Endeavour’s launch window, which is restricted by a launch beta angle cut out on November 25.

Another issue relates to an effort to add up to an additional 1,750 lbs of payload inside Endeavour’s “Leonardo” Multi-Purpose Logistics Module (MPLM), with analysis into the best case scenario being hit by a week-long delay due to the shut down of JSC during Hurricane Ike.

The analysis of several options to increase what is already the heaviest logistics flight to the International Space Station (ISS) centered around the results of the Verification Loads Assessment (VLA), which initially raised concerns.

However, the process is now coming to a conclusion, via NASA SE&I (NASA Systems Engineering and Integration) and the MPLM’s contractor, Alenia Space of Italy, on what now appears to be more conservative 600lb increase to the MPLM’s cargo – added to the end cone of the module.

“On STS-126, the model for the MPLM and cargo was delivered to SE&I last week. Alenia brought forward their analysis that showed the 600 lbs. case. The Structures Working Group is happy with that. This is for the end cone mass on the MPLM,” noted the latest Shuttle Stand-up/Integration report this week.

“It turns out that the mass stowed in the bags is 590 lbs., 420 lbs. of which is actual stowage to go in logistics. Got Coupled Loads Analysis (CLA) results. CLA is where the Cargo Mission Contract (CMC) folks run a pseudo-VLA and pass results back to our folks to put uncertainty factors on.

“We got the results back from the over/out-of-tolerance rack case for the MPLM (3 or 4 racks out of tolerance). Are currently working up uncertainty factors for those racks, but it looks like it will be pretty good. Also, their return case is very light, below our VLA tolerances, so they are also doing a CLA for that.

“We should see where that is this week. We will apply uncertainty factors on our VLA Cycle 2 case results based on these results, and hopefully clear that case too. Think the critical path now is SE&I/Orbiter guys.”

Endeavour’s logistics run to the ISS involves key delivery of items required to support the expansion to a six man crew on the Station next year.

Discovery STS-119/STS-129:

While Atlantis awaits her rollback confirmation, work has been proceeding at a good pace inside OPF-3 with Discovery, as she readies for her primary mission of STS-119 - and now the potential of “STS-400″ requirements.

A key milestone was reached in processing over the past week, with the installation of her three Space Shuttle Main Engines (SSMEs), and continued progress with the boundary layer transition modification – which will gain valuable data on Thermal Protection System (TPS) performance during re-entry.

“Completed engine installation on Friday. picking up with engine securing and get into leak check,” added the Stand-up. “On the boundary layer transition mod, have completed all the wiring. Will start bonding the tile this week. This activity is going well.”

“Orbiter docking system pyro system checkout was completed Monday and is good. Nose landing gear thermal barrier rework was removed Monday and new thermal barrier were ordered because the ones delivered did not meet requirements,” added processing information.

“Post SSME installation engine securing is in work through Wednesday. Radiator functional testing is scheduled for Tuesday and Wednesday.”

One of Discovery’s future flights – STS-129, currently set to launch in October, 2009, though likely to slip - also received official confirmation of the crew assignments to the mission.

As revealed by NASASpaceflight.com a month ago, the crew will consist of Marine Col. Charlie Hobaugh as commander, joined by Navy Capt. Barry Wilmore as pilot. The Mission Specialists are Robert Satcher, Navy Capt. Michael Foreman, Marine Lt. Col. Randy Bresnik and Leland Melvin.

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

Related posts:

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2. Hubble control system failure – STS-125 launch date delayed A major failure of the “Side A” control system on...
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The failure has shut down Hubble’s science operations, and is currently unable to send data back to Earth. Attempts will be made to switch to the “Side B” control system later this week.

Switching over to the Side B control system has never been attempted in the lifetime of the telescope.

“Side A of the CUSDF (Control Unit/Science Data Formatter) in HST went into safe hold, this means science operations have stopped. The spacecraft is still operational but unable to operate the instruments,” noted information acquired by L2.

“Attempts to recover the A side have failed so the project is now working to transfer science operations to the B side, this requires transferring the whole spacecraft from Side A to Side B so its a significant operation.

“Side B side has not been operated on orbit, for HST’s entire on orbit service life it has operated on Side A. However, the B side was fully tested before launch.

“The plan as of now is to complete the transfer to the B side later this week. The details for this will be provided later by the project.

“If the B side comes up fine we could still launch on time so I propose that we do not postpone the (Agency) FRR (Flight Readiness Review) at this time.”

However, later in the day, both the FRR and the process of switching to Side B were delayed.

“If the B side does not come on line then we clearly have no mission as there is no way to get science data down,” the memo warned.

Evaluations are taking place on whether a replacement control system – to return redundancy to the telescope – will now be required to launch with STS-125. If this becomes the case, the mission would have to wait until the replacement part has been tested and sent to the Kennedy Space Center (KSC).

Those evaluations have now resulted in the delay of STS-125 until at least Feb, 2009 based on replacing the failed unit. This is due to a long process of testing Hubble’s switch to Side B, and the new training that the crew will undergon for STS-125′s mission.

Optional plans are being drawn up, which include launching Endeavour on STS-126 in November, and Atlantis to Hubble in February or at another time in the first quarter.

“Options are in work. Earlier we had a plan to launch STS-126 first in November and follow up with HST in Feb. with the Feb. 2009 flight as back-up,” added one response to the memo.

“We will dust off our plans and see what we can do.”

Three plans are being looked at for re-arranging the near term launch manifest, as listed:

1. Keep Atlantis and Endeavour on Pad A and B, wait for a repair/switch over to Side B of the CUSDF if possible and the launch in the currently scheduled sequence - now dismissed.

2. Launch STS-126  from Pad B before STS-125 launches from Pad A. STS-119 would roll to Pad B as the LON for STS-125.

3. Swap pads in order to launch STS-126 from Pad A before STS-125.  STS-125 would be “stored” at Pad B.  After STS-126 launch, STS-125 will go back to Pad A and STS-119 would be integrated and rolled to pad B as the 400 HST LON mission.  STS-125 would launch from Pad A.

However, it is now confirmed that STS-125 will not launch before mid February. This has caused a review of the schedule’s Time and Cycle requirements.

Managers are requesting that any managers that have a concern about Atlantis staying at the Pad for an extended period should forward their concerns for further evaluations this week.

This will allow any potential issues to be debated, particularly if there are any requirements that would require Atlantis to de-stack or roll back to the OPF as opposed to stay at the Pad.

Fallout from the delay will be felt by the Constellation Program, which now have to delay Ares I-X – due to Pad 39B requirements – from its April, 2009 launch date.

Another article will follow on Tuesday, based on updated options.

Related posts:

1. STS-125 launch target moves to February 17 – crucial week for Hubble STS-125 has been given a new “work-to” launch date of...
2. Atlantis to rollback to VAB on October 20 – Hubble troubleshooting latest As NASA and the SSP (Space Shuttle Program) refine their...
3. Hubble switchover efforts to Side B completed – Suffers more problems The complicated task of remotely switching the Hubble Space Telescope...