Highlighting the second half of 2009 for NASA was the resolution of the Gaseous Hydrogen leaks at the Ground Umbilical Carrier Plate on the Shuttle launch pad (which resulted in the successful launch of STS-127/Endeavour in July), the midnight ride of Discovery on STS-128 in August, the amazingly successful test flight of the Ares I-X rocket in October, the discovery of water on the moon in October/November from the Lunar CRater Observation and Sensing Satellite and the Lunar Reconnaissance Orbiter, and the logistics run of shuttle Atlantis to the ISS in November.

*See also 2009 Review Part 1*

The Gaseous Hydrogen Leaks and the STS-127 – LRO/LCROSS Range Debate:

Kicking off the second half of 2009 for NASA were the launch campaigns for shuttle Endeavour’s STS-127 mission to deliver the Japanese exposed experiment facility to the ISS and the Lunar Reconnaissance Orbiter (LRO) and shepherding spacecraft Lunar CRater Observation and Sensing Satellite (LCROSS) on the Atlas V rocket.

Initially targeting a June 13 liftoff for STS-127, the main constraints facing NASA for Endeavour’s launch window were the scheduled June 17 launch of the LRO/LCROSS mission – a mission which only had a 3-day launch window before standing down until early July – and an imposing Solar Beta Angle Cutout with the ISS that began on June 20 and ran through July 10.

Given the Eastern Range’s need of roughly 48-hours to reconfigure all their tracking and communication equipment between the various vehicles launched from the Cape Canaveral area, Endeavour was constrained to a 3-day launch window in the early morning hours of June 13, 14, and 15 in order to allow LRO/LCROSS to launch on June 17.

This plan was thwarted, however, in the evening hours of June 12 as launch personnel were nearly finished fueling Endeavour’s External Tank (ET) with over 500,000 gallons of Liquid Oxygen (LOX) and Liquid Hydrogen (LH2).

Just before the LH2 tank of the ET entered stable replenish mode, launch personnel noted an abnormally high concentration of gaseous hydrogen around the Ground Umbilical Carrier Plate (GUCP) assembly – a system used to vent the extremely flammable gaseous hydrogen (caused by LH2 boil off inside the LH2 tank) safely away from the Shuttle stack.

Following the scrub of Endeavour’s first launch attempt, NASA mangers reported that the signature of the leak was “nearly identical” to the leak seen during the first launch attempt of STS-119 in March. Since the Removal and Replacement (R&R) of the GUCP Quick Disconnect seals fixed the leak back in March, NASA managers decided to repeat the R&R procedure after obtaining critical data on the area of the leak for a root cause investigation.

However, the R&R of the seals meant that launch of Endeavour would not be possible until the early morning hours of June 17 – two days past the end of Endeavour’s launch window because of the Eastern Range launch conflict with the scheduled June 17 launch of LRO/LCROSS.

Nonetheless, engineers pressed forward with the R&R of the GUCP Quick Disconnect seals while the Agency as a whole began discussions on which mission now had priority.

Ultimately, through cooperation between the Space Shuttle Program, the LRO/LCROSS team, and the Eastern Range, a compromise was reached in which Endeavour would be given a launch opportunity at 5:40a.m. on June 17 while the LRO/LCROSS team would proceed toward a late afternoon/early evening June 18 launch with the understanding that if Endeavour launched on June 17, LRO/LCROSS would have to be delayed until June 19 – the last day of the LRO/LCROSS’ June launch window – because of Eastern Range reconfiguration time constraints.

Per the terms of the agreement, should Endeavour launch on June 17, LRO/LCROSS would take an additional one day delay and launch on June 19. However, should Endeavour scrub for any reason prior to 12 midnight June 17 (a scrub on calendar day June 16), the Eastern Range would undertake a 36-hour reconfiguration effort to allow LRO/LCROSS to maintain its ~5p.m. June 18 launch date/time.

As it would be, the GUCP leak reoccurred during ET fueling on June 16/17 and the launch was officially scrubbed at 1:55a.m. EDT. Later, Shuttle Program managers stated that they would not try to launch Endeavour before July 11 to allow for an investigation into the GUCP leaks.

However, the scrub came nearly two hours after the midnight deadline for LRO/LCROSS on June 18. Nonetheless, the Eastern Range undertook the reconfiguration effort and completed these operations on time for the June 18 launch of LRO/LCROSS. That day, during the final minute of the launch window, the Atlas V rocket carrying LRO/LCROSS lifted off from its seaside launch pad, returning NASA to the moon.

In the days that followed the second scrub of STS-127, engineers focused their attention on a minor misalignment between the GUCP and the External Tank Carrier Assembly (ETCA), the component on the ET to which the GUCP is mated.

In the end, the ETCA was realigned using high fidelity 0.515″ alignment pins and the Flight Seal in the GUCP was replaced.

Once the R&R procedure was complete, a tanking test was performed on July 1 to verify the integrity of the repair and confirm that no leaks were present. The tanking test was a success and no leaks were detected.

This paved the way for the July 11 launch attempt of Endeavour, which was postponed prior to fueling because of extra time needed to clear all of Endeavour’s systems following a lightening strike within the Pad-A perimeter the previous day.

Launch was rescheduled for July 12 but was scrubbed at the T-9 minute and holding mark due to unacceptable weather around the Kennedy Space Center. The launch was further scrubbed on July 13 – again at the T-9 minute and holding mark – due to adverse weather.

NASA stood down on July 14 to replace the Tyvek covers on Endeavour’s Reaction Control System jets and retargeted launch for July 15. The countdown on July 15 was uneventful and at 18:03:10 EDT (6:03:10p.m.) Endeavour lifted off from Pad 39A – on the third Shuttle mission of the year – one day shy of the 40th anniversary of the Apollo 11 launch from the same pad.

In all, STS-127 was the longest Shuttle flight of 2009 lasting nearly 16-days. During the course of the mission, Chris Cassidy became the 500th person to fly into space, a record 13 people lived and worked on the ISS during Endeavour’s docked mission (thanks to the increase of the permanent ISS crew from three people to six people at the end of May 2009), five EVAs (spacewalks) were performed, the Japanese experiment exposure facility was installed to the Japanese Kibo module, and six P6 truss batteries were R&R on the ISS.

Endeavour and her seven member international crew landing safely at the Kennedy Space Center at 10:48a.m. EDT on July 31st on the mission’s first landing opportunity, completing a 15day 16hour 44minute 58second flight.

STS-128 – ET Foam Loss Investigation and PV-12 Fill and Drain Valve Discussion:

With the successful completion of STS-127, attention turned to the next Shuttle mission: the STS-128 logistics flight of Discovery scheduled for late-August.

STS-128′s ground processing flow proved to be extremely interesting, with engineers working through issues with a Solid Rocket Booster Check Valve Filter Assembly, an ET Ice Frost Ramp foam void indication, a Main Bus Controller anomaly, and an Ordnance Cable issue on the ET Vent Arm System.

However, it was the numerous foam liberations from the Intertank region on Endeavour’s External Tank during her July 15 launch that kick started an investigation into why the foam liberated – an investigation that once again highlighted NASA’s strict standards of safety when it comes to the Space Shuttle fleet.

While plug pull tests on Intertank foam from Discovery’s ET confirmed the integrity of the foam bond to that tank, NASA managers demanded that they have all the information possible before clearing Discovery for flight.

In fact, the standard one day Space Operations Mission Director (SOMD) Flight Readiness Review (FRR) at the Kennedy Space Center – the FRR that formally approves each mission for launch – required an additional half day to complete all the necessary discussions.

As such, the possible root cause scenarios for the foam loss coupled with the extremely positive results from over 100 plug pull tests on the backside of the Intertank region on Discovery’s ET gave NASA managers the confidence needed to proceed with launch.

In the end, Discovery was approved for liftoff on August 25 at 1:36a.m. EDT. The countdown was uneventful from a technical perspective; however, heavy rains and lightening over the launch pad and in the KSC area resulted in a scrub of the August 25 attempt at the T-9minute and holding mark.

Launch was reset for the following day. Nonetheless, during fueling operations of the External Tank, the inboard LH2 PV-12 fill and drain valve on Discovery did not close when it was commanded to do so.

Launch Director Pete Nickolenko followed the Launch Commit Criteria (LCC) to the letter, calling a scrub and ordering the draining of Discovery’s ET.

For a stuck “open” fill and drain valve, LCC prevent launch personnel from attempting to cycle the valve under cryogenic conditions (meaning in the presence of Liquid Hydrogen or Oxygen). The theory behind this LCC is that – if there is a serious problem with the fill and drain valve – the launch team does not want to put themselves into a situation where they cycle the fill and drain valve closed and then cannot get it open again.

While the launch team followed these procedures to the letter, there were indications from sensors – both upstream and downstream of the PV-12 fill and drain valve – that the valve had indeed closed when commanded, and that the “open” indication was a sensor error in the valve itself.

As such, engineers conducted multiple ambient (meaning without the presense of Liquid Hydrogen) cycles of the valve. During these tests, the valve performed nominally.

This allowed Shuttle mangers to approve a third launch attempt for Discovery 22-minutes after midnight on Friday, August 28 while they reviewed a potential revision to the current LCC document (actually a reversion to a previous LCC rule) that would allow them to cycle the PV-12 valve under cryogenic conditions should they receive a sensor indication that the valve failed to close on the Friday morning attempt.

Nonetheless, extensive engineering conversations took place in regard to this LCC change and the possible scenarios that could occur if they launched with a PV-12 valve that was only partially closed or a valve the became stuck “closed.”

“Based on a concern with galling failure mode within the valve driver mechanism, the previous LCC was amended to preclude valve cycling under cryo conditions,” noted a NASA processing report on the engineering analyses.

“Previous LCC allowed for a repeat valve cycle attempt given the following conditions were met: No Sustained reg-out demand occurs. No sustained increase in Aft Haz Gas helium concentration. Initial move time <5.0 seconds. All the above parameters were satisfied.”

In the end, NASA managers decided they needed additional time to review all the information and complete closeout paperwork on the PV-12 valve issue. To this end, launch of STS-128 was postponed 24-hours to 23:59 EDT (11:59p.m.) on Friday, August 28 – the second launch opportunity of the calendar day but technically a 24-hour delay to the launch.

The final countdown on August 28 was uneventful and the PV-12 valve “closed” when it was commanded to do so.

In fact, the countdown went exactly as expected and at 11:59:37p.m. on August 28 Space Shuttle Discovery lit up the midnight sky of Central Florida, becoming the only manned mission to launch on one calendar day and reach orbit on the next.

Two days later, Discovery docked to the International Space Station 25 years to the day after the launch of her maiden voyage: STS-41D. That day, Nicole Stott – who launched on Discovery – officially transferred to the ISS crew, becoming the final person to rotate up to the ISS on the Space Shuttle.

During the course of the docked mission, Discovery’s crew delivered a second treadmill to the ISS as well as numerous new science experiments and new science racks via the Multi-Purpose Logistic Module Leonardo.

After a highly successful mission, Discovery and her crew undocked from the ISS and received final Thermal Protection System clearance for landing. The first two landing attempts on September 10 were waved off due to bad weather at the Kennedy Space Center.

Discovery was ultimately cleared for landing on September 11 and performed the second Boundary Layer Transition DTO (Detailed Test Objective) during her reentry into the Earth’s atmosphere.

Discovery and her seven member crew landed safety at Edwards Air Force Base, CA at 20:53 EDT (8:53p.m.) on September 11, completing a 13day 20hour 54minute 55second mission.

Ares I-X – Proving Concepts for the Future of Manned Space Exploration:

It was a mission nearly 4-years in the making. The Vision of Space Exploration, set forth by President George W. Bush in January 2004, committed NASA to returning men to the moon and continuing on to Mars – an endeavor that required a new launch architecture system.

Unlike the Space Shuttle, which underwent its first integrated test flight with a crew onboard, NASA’s new Ares I crew transportation rocket was designed to have multiple test flights before launching a crew into orbit.

The first of these test flights was dubbed Ares I-X.

The rocket, a virtually identical model of the Ares I vehicle, was designed to test the avionics and control systems of the Ares rocket during the first stage of flight – a two minute propulsion period powered only by a single Solid Rocket Booster (SRB).

As the Ares I design evolved, the SRB grew from a four-segment SRB (as used on the Space Shuttle) to a five-segment SRB. The addition of a fifth segment to the SRB required changes to the SRB’s nozzle, changes that could not be implemented into the design of the Ares I-X test rocket in time for all the data the test flight was meant to gain to be useful to Ares I engineers.

Since the Ares I-X test was meant to demonstrate the ability and performance of the Ares I design, not simulate a full up 5-segment SRB thrust test – a fifth segment simulator was added to Ares I-X to give the rocket the appropriate height and to accurately simulate the airflow over the entire length of the vehicle during the 2-minute powered portion of the flight.

Receiving and integration of the Ares I-X’s Upper Stage Simulator began in early 2009 on the floor of VAB High Bay 4, with full up stacking of the vehicle (SRB and all) beginning in July in High Bay 3 – directly across from High Bay 4.

After stacking of the vehicle was complete in mid-August, nearly two months of integration testing and sensor diagnostics took place, ensuring that over 700 sensors and the avionics and control assemblies of the Ares I-X vehicle were working perfectly.

Then, one week after Shuttle Atlantis/STS-129 was rolled out to Pad-A, the Ares I-X vehicle emerged from the VAB in the early morning hours of October 20 – marking the first time since 1975 that a vehicle other than the Space Shuttle was rolled out of the VAB.

One week of launch pad operations and processing followed for Ares I-X – a timeframe that was increased from the original four day pad flow to accommodate the dual pad flow nature of I-X processing with the ongoing processing of Space Shuttle Atlantis on nearby Pad-A.

In fact, Ares I-X shared many of the pad workers who were also busy processing Shuttle Atlantis for STS-129 in November. As a result, these workers undertook the second dual pad flow of 2009 – accomplishing both flows in time for Ares I-X’s and Atlantis’ respective launch windows.

With the countdown beginning at 1a.m. on October 27 for a launch window of 8a.m. through 12p.m., the Ares I-X launch team configured the vehicle and, after waiting out the weather and a cargo ship in the SRB recovery zone, gave the go to resume the countdown and launch Ares I-X.

The countdown resumed from the T-4 minute and holding mark and counted down to T-2minutes 39-seconds – at which point Ares I-X weather officer Kathy Winters ordered a hold due to a violation of the triboelectrification weather rule.

The resulting hold mandated a recycle of the countdown to the T-4 minute and holding mark, a milestone that was accomplished in a timely manner. The launch team then waited on the weather, before eventually scrubbing the October 27 launch attempt and announcing that a second launch attempt would be made on October 28.

On the morning of October 28, the countdown once again began at 1.a.m. EDT for an 8a.m. through 12-noon launch window. During the course of the morning, the T0 time was continuously realigned to reflect changing weather conditions.

Finally, a go was given by the launch team to proceed with launch at 11:30a.m. EDT – in the center of a patch of good weather.

The countdown resumed at 11:26a.m. and proceeded without issue. At 11:30a.m. on the nose, the Ares I-X’s SRB ignited, propelling the vehicle off of Launch Pad 39B and off onto a due east trajectory from the Kennedy Space Center.

Two minutes later, the SRB burned out and successfully separated from the Upper Stage Simulator, parachuting into the Atlantic Ocean 130 nautical miles east of KSC.

Ares I-X managers and NASA hailed the test flight a smashing success. All five the flight’s primary test objectives were accomplished, giving NASA invaluable data on the performance of a single SRB first stage powered launch vehicle.

Despite the uncertain nature of the Ares I rocket’s role in whatever the future of NASA’s manned space endeavors becomes, the test flight of Ares I-X proved the concept of the Ares I first stage design and provided the engineering community with copious amounts of scientific data that can be used in the development of future U.S. launch vehicles.

Water on the Moon! – LRO and LCROSS’s Enormous Discovery:

On October 9, the LCROSS satellite and its Centaur Upper Stage impacted the moon’s south pole in the Cabeus crater. Their mission was to expose the unseen material beneath the surface of the Cabeus crater – looking for signs of water, of the past presence of water, beneath the moon’s surface.

Trailing its Centaur upper stage by four minutes, the LCROSS conducted hundreds of scientific observations of the ejecta plume created by Centaur’s impact before it too impacted the Cabeus crater, creating a second ejecta plume of denser material for analysis by the Hubble Space Telescope and Lunar Reconnaissance Orbiter.

On November 13, the preliminary results of the impacts were released by NASA, and the answer to the age old question of whether water currently exists on other bodies in our solar system was finally put to rest.

The answer was a resounding yes. Water exists in the permanently shadowed crater Cabeus on the moon’s southern pole.

“We’re unlocking the mysteries of our nearest neighbor and by extension the solar system. It turns out the moon harbors many secrets, and LCROSS has added a new layer to our understanding,” said Michael Wargo, chief lunar scientist at NASA Headquarters in Washington D.C.

In fact, the LCROSS results have shed light on the mystery surrounding the large concentrations of hydrogen observed on the moon in the past decade. Given the current evidence, NASA suspects that water may be far more prevalent and exist in much larger quantities on the moon than originally theorized.

But just how much water is on the moon is still unknown. “Multiple lines of evidence show water was present in both the high angle vapor plume and the ejecta curtain created by the LCROSS Centaur impact,” stated Anthony Colaprete, LCROSS project scientist and principal investigator at NASA’s Ames Research Center in Moffett Field, California. “The concentration and distribution of water and other substances requires further analysis, but it is safe to say Cabeus holds water.”

The results of the LCROSS experiment hold significant implications for the current NASA plan to establish a permanent, manned colony near one of the moon’s poles. If water is present in large quantities beneath the moon’s surface, future inhabitants of a lunar colony could make use of that water, providing valuable lessons on how to use natural materials/substances around the colony – lessons that could be applied to future manned missions into the solar system.

STS-129 – Stockpiling the Space Station:

Continuing on the theme of preparing for the future, 2009 came to a close for NASA with the highly successful flight of Space Shuttle Atlantis on the STS-129 mission.

After initial worries and conversations about range conflicts with an Atlas V and Delta IV rockets, both vehicles encountered launch delays – giving Atlantis the full duration of her short launch window in mid-November, a launch window that was constrained by a Solar Beta Angle Cutout from November 20 – December 5.

Officially approved for a launch on November 16, Atlantis’ processing teams saw double work with the dual pad flow of Atlantis and Ares I-X. After the successful launch of Ares I-X, work proceeded in earnest on Atlantis with installation of the Express Logistics Carriers (ELCs) -1 & -2 into Atlantis’ payload bay as Program engineers and managers worked through a Main Engine Ignition (MEI) overpressure issue.

The issue, relating to the acoustic environment present at the aft of the vehicle during SSME (Space Shuttle Main Engine) ignition was brought to the attention of Program managers when it was discovered that bolts used to attach the aft stinger pods to the OMS Pods might not be sufficient to counter the acoustic environment.

Through an aggressive engineering review of all information pertaining to the MEI acoustic environment and the stinger pod bolts, Program managers were able to clear Atlantis for flight after installation of several new sensors on Atlantis and the Mobile Launch Platform to obtain as much data as possible during the vehicle’s launch.

With launch officially approved, Atlantis’ countdown began on Friday, November 13 at 13:00 EST (1p.m. EST) for a targeted 14:28 EST (2:28p.m.) liftoff on November 16.

Atlantis’ countdown was uneventful and – with the lowest number of PRs (Problem Reports) in the history of the Shuttle Program – STS-129 lifted off at 14:28:09 EST November 16 on its first launch attempt, making Atlantis the only Orbiter to launch on her first attempt for both of her 2009 missions.

After docking with the ISS, Atlantis’ six member crew installed both ELCs onto the Integrated Truss Structure of the Space Station – thereby delivering nearly 30,000 lbs of spare parts that will enable the ISS to remain operational well into the next decade.

Three EVAs were also performed on STS-129 and Nicolle Stott transferred to the Atlantis crew before orbiter undocked from the ISS the day before the Thanksgiving holiday in the U.S.

After performing the customary late inspection of their vehicle’s Thermal Protection System (TPS), Atlantis’ crew enjoyed Thanksgiving on orbit before receiving final TPS clearance to land.

On Friday, November 27, Atlantis and her now seven member crew glided to a perfect landing at the Kennedy Space Center at 9:44:22a.m. EST, completing a 4.4 million mile mission in 10days 19hours 16minutes and 13seconds.

In all 2009 was a year of tremendous accomplishments for NASA and its dedicated workforce.

As Mike Moses, KSC Launch Integration Manager, stated “this was really about the teams and their ability to go above and beyond what we asked of them. When you think about the fact that we worked through the Flow Control Valve issue, the hydrogen leaks, and many more things and still flew five successful Shuttle missions, had two dual pad flows (three if you count the first STS-125/STS-400 flow last year), launched an experimental rocket, and mated Endeavour for STS-130 next year – all within one calendar year – that’s pretty amazing.

“It really shows the level of dedication of the teams out here and their ability to remain flexible.”

For a video review of NASA outstanding year, see Max-Q Entertainment’s Year In Review video click here

For NASA, 2010 begins with preparations and Flight Readiness Reviews for Space Shuttle Endeavour’s STS-130 mission, currently targeted to launch at 4:39a.m. on February 7.

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In-Flight Anomalies from Previous Vehicle Flight (STS-125):

Perhaps the most prominent In-Flight Anomaly experienced by Atlantis during her flagship mission to the Hubble Space Telescope in May was the failure of the ASA-1 (Aerosurface Servo-amplifier Assembly channel One) system.

“Immediately before launch, all aerosurface servo-amplifier assembly (ASA) channel one positions went off scale low,” notes the Orbiter Project Office’s (OPO’s) presentation to the SSP FRR in mid-October.

As a result, the Remote Power Controllers in Atlantis were tripped approximately 1-second after SRB (Solid Rocket Booster) ignition – which caused the annunciation of the Caution and Warning alarm on Atlantis’ Flight Deck.

Given the redundancy in the system, Atlantis’ crew was told to bypass the ASA-1 system. Flight Controllers monitored the remaining three ASA channels throughout Atlantis’ mission – as the failure of two ASA channels would have meant an early termination of the flight.

After Atlantis’ landing at the Dryden Flight Research Center, limited troubleshooting was performed – troubleshooting that did not reveal any shorts in the ASA system.

After Atlantis was ferried back to the Kennedy Space Center, the ASA-1 was Removed and Replaced (R&Red), with Hi-pot testing of the Right Hand (RH) inboard elevon’s primary delta pressure transducer circuit indicating a “short to ground.”

All other ASA-1 circuits with “400 Hz excitation voltage were Hi-pot tested.” No further anomalies were detected.

However, troubleshooting did not end there. “Further isolation and inspection found discrepant wire harness chafing against an adjacent Hi-Lok fastener in the actuator cavity region,” notes the OPO presentation – available for download on L2.

These wire harnesses were removed for failure analysis, which revealed the cause of the ASA-1 failure to be an “exposed conductor within the wire harness shorting to the Hi-Lok fastener.”

Furthermore, the Test, Teardown, and Evaluation (TT&E) and failure analysis at the NASA Shuttle Logistics Depot (NSLD) of ASA-1 verified that the short was external to the LRU – which caused the failure of the ASA-1 excitation card,” notes the OPO presentation.

Following the replacement of this card, ASA-1 was subjected to an ATP (Acceptance Test Procedure) vibration test. No shorts were monitored during this testing.

Overall, Flight Rationale for the ASA system has been documented and accepted by the Space Shuttle Program (SSP) and the Space Operations Mission Directorate (SOMD), which both cleared the issue for STS-129.

Given that the damaged wire harnesses were identified and replaced, that ASA wire redundancies were assessed and deemed to be well within safety standards, and that extensive, hands-on investigations of the redundancy systems were carried out, the ASA system is not expected to be an issue for Atlantis and STS-129.

Nevertheless, during these hands-on inspections, “two areas of redundancy routing violations were identified and corrected, remaining Right and Left Hand inboard/outboard elevon actuator harnesses were inspected for damage, and overbraid damages were repaired,” notes the OPO presentation.

Additionally, harness routing locations in the RH and LH elevons were re-documented and further baseline wire inspections were performed in the wings, vertical stabilizer, main landing gear wheel wells, and struts to “increase confidence in overall system integrity.”

In all, 27 Problem Report “conditions” were detected and repaired on OV-104 (Atlantis) during these wiring inspections. As such, Atlantis is cleared for flight on STS-129.

In addition to the ASA-1 issue, turnaround flow engineers faced another issue with Atlantis – in the form of a “quick show mount knob” that was found to be wedged between pressure pane #5 and the console dashboard close-out panel.

Engineers and technicians tried several times (using several different methods) to remove the wedged knob.

“After a number of methods were utilized to remove the knob without inducing further damage to the pressure pane, the knob was successfully removed without further damage to the pressure pane by chilling the knob while employing mechanical motion and pressurizing the crew compartment (2-3 psig).”

This pressurization of the crew compartment was attempted after careful consideration and analysis on the possible effects of pressurizing the crew compartment at sea level.

Originally, it was thought that pressurizing the crew compartment would not be possible because of over press concerns. However, the low pressurization rate was approved in order to provide more room between the pressure pane and the console dashboard close-out panel.

This procedure was approved as part of the effort to free the knob – which, based on engineering safety margins, had to be removed prior to the next flight of orbiter Atlantis.

Nevertheless, once the knob was removed, an extensive inspection and analysis of the damage induced to the pressure pane from the knob’s edge was undertaken to ensure that flight safety margins on the pressure pane had not been breached.

“Mold impressions were taken and the larger of the defects to the pressure pane measured 0.00035 inches deep,” notes the OPO presentation. “Per the MT0501-514 spec; scratches, dings, and impact with depths exceeding 0.0015 inches are reportable to Design Engineering.”

This proved to be extremely positive news as the defect was not large enough to mandate the replacement of pressure pane #5 – an endeavor that would have taken at least one year to accomplish and could have resulted in Atlantis’ permanent removal from flight status.

Based on mold impressions taken of the damage site, the Micro Inspection Team (MIT) was able to confirm the integrity of the pressure pane and thus clear this issue for flight.

In-Flight Anomalies from Previous Program Flight (STS-128):

Highlighting the remarkable job by ground processing engineers was the near complete lack of IFAs carried forward from the previous program flight – STS-128 and the Space Shuttle Discovery.

In fact, aside from the normal review of the Thermal Protection System (TPS), only two IFAs from STS-128 were discussed during the FRR season for STS-129.

The first of these IFAs was, in fact, a ground issue experienced by the Launch Team during the second STS-128 launch attempt.

“During the transition to reduced fast fill (85 percent), the LH2 (Liquid Hydrogen) inboard fill and drain valve (PV12) closed position indicator (PI) did not come on when the valve was commanded closed,” notes the OPO presentation.

This was a violation of Launch Commit Criteria (LCC) MPS-04 (Main Propulsion System 04). As such, a 48-hour scrub was called and an ambient cycling test of the PV-12 valve performed once ET (External Tank) boil-off was complete.

During the ambient test, the PV-12 valve functioned as designed, with no anomalies detected.

“Data obtained following ET drain, along with historical valve cycle timing and low pressure actuation test data concluded that the failure was most likely the valve position indicator and not a failure of the valve to cycle properly.”

As such, an LCC deviation was accepted by the Mission Management Team (MMT) for STS-128 – which would have allowed for the launch of STS-128 if the Launch Team could have verified the closure of the PV-12 valve even if the sensor issue reappeared.

However, the LCC deviation proved unnecessary as the PV-12 valve and associated sensors worked perfectly during the third and final launch attempt for STS-128.

Post-flight borescope inspections identified “contamination under the close micro-switch arm,” notes the OPO presentation. “Contamination dislodged during removal attempt; other retrieved material consisted of putty with embedded foam and metal shaving.”

Similar borescope inspections were performed on Atlantis, which revealed that OV-104′s PV-11 valve was worn where contact with the actuator cam occurs. There was also a minor “ding” noted on the PV-9 valve.

The PV-9 valve “ding” was accepted for flight, while the PV-11 valve was R&Red.

The second issue from STS-128 brought forward to the STS-129 FRR was that of the Forward Reaction Control System (FRCS) F5R thruster.

“During the initial usage of Vernier RCS (VRCS) on the evening of FD-1, the VRCS thruster F5R fuel and oxygen injector temperatures began to drop. The F5R thruster was deselected as Fail Leak when temperatures dropped below 130 deg F limit.”

In all, there was no indication of “safety of flight” issues and all flight rules were followed during STS-128.

Since the VRCS is not mandatory for ISS/Shuttle rendezvous and docking operations – and since no generic fault could be identified for the failure of the F5R thruster on Discovery – there is no constraint for STS-129 and Atlantis.

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.

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Ares I-X Attempt 2 (pre-launch):

The first launch attempt on Tuesday was delayed for 24 hours due to several weather rule violations, including excessive wind speeds at the launch pad – which were exceeding the 20-knot limit – along with concerns about clouds with moisture that could have caused static build-up on the rocket and led to communication issues – known technically as triboelectrification.

With slight delays caused by issues other than the weather – such as the problem with the removal of a protective cover from the top of the vehicle and the ship that breached the strict Eastern Range exclusion zone – time was lost prior to coming out of the four minute hold.

At one point, the count managed to head past the hold and got as close to as two and a half minutes to launch, before the weather once again closed in – with Weather Office Kathy Winters giving notice of unacceptable conditions at T-0.

While lightning and rain were observed near the launch pad overnight, forecasters were more hopeful for acceptable conditions for the Wednesday launch attempt, predicting a 60 percent chance of favorable weather, with four hours of window available to launch director Ed Mango. However, triboelectrification weather conditions moved the launch back to 11:30am Eastern.

Recent – over the past one year period – Ares I-X Articles on NASASpaceflight.com can be found on this link:
http://www.nasaspaceflight.com/tag/ares-i-x/

Key Launch Events:

With the countdown overviewed in the opening launch attempt article, Wednesday’s attempt focused on the launch events, as Ares I-X opened the flight test era of the Ares launch vehicle program – albeit a program that may yet be cancelled in the coming months.

At liftoff, Ares I-X will weigh 1.8 million lbs, with the four segment SRB providing between 2.6 and 3.3 million lbs of thrust that will propel the Ares I-X to a height of 130,000 ft. The SRB nozzle will be gimbaled at Mission Elapsed Time (MET) 0.1 seconds for the “fly away” maneuver (designed to pull I-X away from the launch tower). First motion off the MLP is expected at MET 0.2 seconds.

The RoCS (Roll Control System) will be enabled and the 90-degree roll program started at MET six seconds. The “fly away” maneuver will be considered complete at MET 20-seconds.

For the first 91 seconds of flight, the RoCS system will be activated every 10 seconds to counter any axial roll of the vehicle. MaxQ is expected at ~MET 50 seconds. The Flight Control System phase of flight will transition into the separation phase of flight at MET 2 minutes 00.6 seconds.

According to flight timelines, SRB burnout is expected at MET 2 minutes 4 seconds; however, the latest possible time of SRB burnout is MET 2 minutes 12 seconds. As such, all further flight times are based on this no later than SRB burnout time.

The Booster Deceleration Motor and Pyro Initiator Controller will be armed for separation at MET 2 minutes 13.9 seconds with the Thruster Vector Control system commanded to “null” and RoCS deactivated at MET 2 minutes 14 seconds. The SRB APU will be shutdown at MET 2 minutes 14.5 seconds.

Eight Booster Deceleration Motors will fire at MET 2 minutes 14.9 seconds, followed 0.1 seconds later by First Stage and USS separation. The Booster Deceleration Motors are designed to pull the SRB clear of the frustum and USS.

At the time of SRB and USS separation, the Ares I-X will be travelling at approximately mach 4.76 at an altitude of 130,000 ft. The maximum acceleration force during flight will be 2.48 g. The SRB tumble motors will fire at MET 2 minutes 18-seconds, inducing a horizontal tumble into the SRB’s profile. This will increase drag on the SRB, preventing recontact with the free flying USS and slowing the SRB down during reentry.

The Recovery Control Unit pyro will be armed at MET 2 minutes 45-seconds.

Booster parachutes in focus:

After coasting to an altitude of 150,000 ft, the parachute system will engage at 16,000 ft (or MET 5 minutes 15 seconds) with the deployment of pilot chutes. The main chutes will be deployed at MET 6 minutes 15 seconds, brining the SRB to a manageable speed for splashdown in the Atlantic.

The First Stage nozzle will be severed from the SRB at MET 6 minutes 35 seconds, with splashdown occurring ~147 miles downrange from KSC just prior to MET 7 minutes. The USS will also coast to approximately 150,000 ft before plunging into the Atlantic Ocean at near terminal velocity. The USS is expected to break apart upon impact with the water and sink to the ocean floor.

The parachute recovery system is the most mature element of the Ares hardware that is currently under development.

Several tests have been carried out at the US Army Yuma Proving Grounds on the giant parachutes which are set to return the five segment Ares I first stage to a splash down in the Atlantic Ocean.

The latest successful test was just this month, with a 72,000 pound test payload, including the Jumbo Drop Test Vehicle (JDTV), dropped from the back of a US Air Force C-17 aircraft at 25,000 feet – designed to test the design load limits of the Ares I main parachute system.

Engineers from NASA’s Marshall Space Flight Center (MSFC) manage the team conducting the tests, designed to place 100 percent of the flight dynamic pressures on the main parachute canopy.

The main parachute, measuring 150 feet in diameter and weighing 2,000 pounds, is the largest rocket parachute ever built and the primary element of the vehicle’s deceleration and recovery system, which also includes a pilot parachute and drogue parachute.

The parachutes work in tandem providing the drag necessary to slow the descent of the huge Ares I solid rocket motor, allowing for a relatively gentle splashdown and subsequent recovery.

While Ares I-X is a four segment motor, an “empty” fifth segment – known as the “XL” motor segment – makes up the first stage. The change of design to the four segment Shuttle booster will result in additional useful data that will be gained after Ares I-X’s powered flight ends.

In fact, the recovery of the First Stage via the parachute system is classed as the Priority 4 task of this test flight: “Demonstrate FS (First Stage) entry dynamics and sequencing of events (parachute deployment, etc.),” noted Launch Readiness Review Documentation (presentations on L2).

“Demonstrate First Stage separation sequencing, quantify First Stage atmospheric entry dynamics, and evaluate parachute performance.”

With the Ares booster recovery system including some of the heritage from the shuttle’s booster systems, issues on the final flights of the shuttle are also providing important information for the next generation of space vehicle.

STS-128 IFA Review highlights SRB parachute failure:

Such information can be seen as recently as the last shuttle mission, STS-128 – when it was revealed by the In Flight Anomaly Review (IFA) review that the main parachute on the Right Hand Solid Rocket Booster recovery system failed, leading to the booster impacting the ocean with a higher than expected force.

The review was conducted at a Program Requirements Control Board (PRCB) meeting, with 15 departments presenting issues found prior, during and after Discovery returned to Earth. A large number of departments noted no issues.

The results of the IFA review created the baseline for the next mission’s Flight Readiness Review (FRR) – namely Atlantis’ STS-129 mission in November, and also Discovery’s next mission – STS-131 next year.

Highlights from the IFA presentations – all acquired by L2 – include the main parachute anomaly on the Right Hand Booster. As with Ares I-X, the booster has three main parachutes that slow the expended booster during its splashdown in the Atlantic ahead of recovery and eventual reuse.

“One of three RH main parachutes failed to fully inflate. Data Acquisition System (DAS) indicated failure occurred 3.9 seconds after frustum separation. Postflight inspection revealed damage on gore number 5 extending from above vent band to skirt band,” noted the STS-128 SRB IFA presentation.

“Parachute on tenth flight. Involved in previous failure on STS-30R. Anomaly Resolution Team (ART-272) formed. Investigation on-going. Booster recovery not affected by loss of one parachute.”

Several conclusions can be noted from the failure, that the booster still survived for potential reuse despite the loss of one of the main parachute, and that this parachute was on its tenth flight and was repaired from an issue it suffered on a previous flight.

The full results of how the parachutes performed with Ares I-X are expected just days after launch, once the booster and recovery systems are examined back in port.

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.

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STS-129 Rollout:

Following a delay relating to one of the crane controls, the rollout slipped by one day on the schedule – although this holds no impact to the pad flow timeline or launch date.

Once mated with the External Tank (ET-133), Atlantis was put through S0008 Shuttle Interface Test operations, which found one issue with a cable relating to the Range Safety Interface Test.

“S0008 Shuttle Interface Test: SSV (Space Shuttle Vehicle) power up was completed at 1551 Saturday evening. Completion of S0008 delayed by IPR (Interim Problem Report): During Range Safety Interface Test attenuator adjustment, AGC levels on RH (Right Hand) side were low.

“Troubleshooting found cables swapped on the facility attenuator panel. However, fixing the cable swap did not correct the low AGC levels. Additional troubleshooting indicated the problem is in other facility cables (one between the HDP (Hold Down Point) to SRB (Solid Rocket Booster) or one from the HDP to the MLP (Mobile Launch Platform) Haunch).

“In order to access these cables for replacement, HDP 2, which is closedout for flight needs to be opened. Cable replacement is in work.”

This issue was resolved within a matter of hours, following the cable replacement and a retest.

“Update: The faulty cables causing the low AGC levels were replaced and the vehicle was powered up to support Shuttle Range Safety System (SRSS) attenuator adjusting, SRSS system interface testing and stray voltage testing which were all successfully completed.”

Rollout of the STS-129 Stack began slightly later than scheduled at 6:38am local time. Despite a stop of around 30 minutes a third the way down the crawlerway, Atlantis arrived at 39A ahead of 1pm.

STS-128 IFA Review (Ascent Imagery):

Closing out the highly successful STS-128 mission in August/September, NASA has completed its series of In-Flight Anomaly (IFA) reviews for the 30th construction mission to the International Space Station. Highlighting the extremely clean nature of the flight is the lack of Ascent Imagery, KSC, Mission Operations Directorate, and general Integrated IFAs for the mission.

As is standard practice for all Space Shuttle missions, NASA’s Imagery Analysis Teams at the Johnson Space Center, the Kennedy Space Center, and the Marshall Space Flight Center conducted a thorough review of all ascent imagery obtained during Discovery’s mid-night launch on August 28th/29th.

The results of that analysis yielded 456 total observations submitted for further analysis.

Of these 456 observations, 13 events were elevated to “reportable” item status. Of those 13, zero were included in the Safety Engineering & Integration Integrated Tracking Matrix and three were included in the Integrated IFA summary.

The first of the 13 “reportable” items came a T-4.153 seconds, when debris was observed “near the port OMS Pod and Payload Bay Door interface,” notes the Ascent Imagery report — available for download on L2.

Currently, this item is classed as “closed” along with five other ascent debris events.

The other “closed” items include possible ice or frost on Discovery at the location of the LH2 (Liquid Hydrogen) T0 umbilical interface at MET (Mission Elapsed Time) 0.73 seconds and debris near the right hand SRB (Solid Rocket Booster) Aft Skirt hold down post #4 at MET 39.6 – 45.2 seconds.

The remaining three closed imagery items include a ruptured GN2 (Gaseous Nitrogen) line which sprayed GN2 onto the left hand SRB Aft Skirt Instafoam at MET 1.039 seconds, “Vapor Traveling Aft on -Z Side of External Tank” at MET 67.4 seconds, and the loss of ET (External Tank) TPS (Thermal Protection System) on the LH2 Intertank Flange.

The remaining seven items are still considered “open.” In order of their occurrence in flight, these items include an ET TPS liberation near the lower right hand corner of the GUCP (Ground Umbilical Carrier Plate) at MET 0.57 seconds and debris “traveling aft along port fuselage” at MET 20 seconds.

Debris was also observed falling aft of the vehicle under the left hand wing of Discovery at MET 21 seconds, a liberation of debris from the +Y thrust strut of the ET at MET 55.7 seconds, and aft-falling debris located near the ET -Y Intertank region at MET 2 minutes 3 seconds.

The final two “reportable” imagery events occurred at MET 2 minutes 4 seconds. These comprised two debris impacts to Discovery’s left hand wing “outboard of the Port Main Landing Gear Door” as observed via the onboard SRB engineering aft forward-facing camera.

Kennedy Space Center IFAs:

All KSC IFAs were reviewed and baselined into the KSC Engineering Review Board (ERB) and presented to the SICB on September 22 – eleven days after Discovery’s landing and 26-days after Discovery’s launch.

In terms of reportable items in the wake of Discovery’s launch at the Kennedy Space Center, STS-128 is one of the cleanest flights in the history of the Shuttle Program.

In all, “no items of special note for KSC,” states the KSC IFA presentation, available for download on L2.

There were no System Specific or General Pad equipment IFAs and no System Specific Government Flown Equipment related IFAs for STS-128.

In fact, only nine general pad debris items met the Problem Reporting and Corrective Action criteria for STS-128 as defined by National Space Transportation System (NSTS) safety guideline 08126.

Of these nine items, six have been closed, with appropriate action assigned to ensure that all open work is complete prior to STS-129 in November.

The remaining three are awaiting final closure documentation and are also not a constraint or concern for STS-129 next month.

Furthermore, six of these were classed as General Pad debris items (which ties the record for second lowest General Pad debris items with STS-123) and three System Specific debris items – the lowest number on record.

There were also zero System Specific Government Flown Equipment (GFE) debris items, which ties STS-128 with STS-119 and STS-125 for the lowest System Specific GFE debris items on record.

Of these nine debris items, eight have been included in the Integrated STS-128 IFA Summary for the Program Requirements Control Board.

With STS-128′s IFAs included, the liftoff debris risk environment is unchanged from pre-STS-128 limits. Currently, the risk of critical Orbiter damage from liftoff debris is classed as “infrequent, catastrophic.”

Mission Operations Directorate IFAs:

In short, the Mission Operations Directorate (MOD) identified no IFAs for STS-128.

However, demonstrating their dedication to safety, the MOD took the time to identify several Non-IFA Items of Interest from STS-128.

The first of these items of interest was the loss of the Vernier thrusters on Discovery during FD-2 (Flight Day 2).

In response to this, the MOD has called for a review of the Reaction Control System (RCS) Flight Rules to better understand the Flight Control Teams’ options should this situation arise on a future mission.

An Orbit Flight Techniques Panel was handed the task of reviewing the Flight Rules, with instructions to report back to the MOD on October 22 with their recommendations/report.

The second item of interest pertained to the PMA-3 (Pressurized Mating Adapter #3) clocking issue observed during one of STS-128′s EVAs.

The root cause of the “PMA-3 clocking issue for heater cable connections is still under investigation through ISS IFI 7361,” notes the MOD presentation, also available for download on L2.

MOD has also begun a review of their internal process for tracking “ISS configuration changes” to ensure that this issue does not happen again.

The next item of interest related to an unexpected pre-launch delay in the Mission Control Center’s (MCC’s) commanding during the MILA (Merritt Island Launch Annex) antenna alignment.

“Second of two planned pre-launch command server selectovers did not perform as expected,” notes the MOD presentation.

The fifth item of interest on the MOD’s list was a problem with the HD TV downlink on FD-10.

“HDTV Downlink Problems (FD10) due to full MPC hard drive in MCC.”

The problem was eventually resolved by purging the MCC MPC hard drive. In the future, the MOD would like to monitor the MCC hard drives more closely and perform purges as-needed to avoid further complications.

The sixth and final MOD item of interest revolved around the scheduling conflict with TDRS 46 (Tracking and Data Relay Satellite 46) during critical phases of the mission.

“Internal MOD scheduling conflict with TDRS 46 for critical periods during eclipse was discovered and corrected prior to final TDRS scheduling,” notes the presentation.

The MOD is investigating the cause of the scheduling conflict in order to have better information on scheduled procedures and channels.

STS-128 Integrated IFA Summary:

In addition to the Ascent Imagery and KSC IFAs that were included in the Integrated IFA Report to the Program Requirements Control Board, the report notes only three additional Integrated IFAs for STS-128.

The first additional IFA related to the LH2 PV-12 inboard Fill and Drain valve inside orbiter Discovery.

The valve, which was on its 16th and final flight due to time cycle requirements which mandate the replacement of each PV valve after 16 flights, failed to indicate closed during the final moments of tanking for STS-128′s second launch attempt.

“On 8/26 launch attempt, during transition to reduced fast fill, LH2 inboard fill & drain valve (PV12) position indicator did not indicate closed when valve was commanded closed,” notes the Integrated IFA Report, available for download on L2. This was a violation of Launch Commit Criteria MPS-04 and resulted in an automatic scrub of the launch attempt.

After de-tanking and boil-off were complete, the valve was cycled at ambient temperatures and performed as designed, with the valve registering closed each time it was commanded closed.

This allowed Mission Managers to develop Flight Rationale and modified Launch Commit Criteria (LCC) for the valve for STS-128 only.

During the launch countdown on August 28, the valve performed flawlessly under cryogenic temperatures — as it had during the first launch attempt of STS-128 on August 25.

The second Integrated IFA pertained to ice buildup external to the LH2 T0 umbilical into orbiter Discovery.

“On August 25 launch attempt, ice buildup was observed on -Z side of LH2 T-0 Umbilical, bridging over to Orbiter TPS. LCC ICE-01 waiver LW-114 approved.”

A similar ice buildup was observed on the August 28 launch attempt and a similar waiver was obtained for flight.

Lastly, the final IFA reported for STS-128 is that of the SSME (Space Shuttle Main Engine) nozzle pinhole leaks.

As first seen on STS-127 – and first reported by NASASpaceFlight.com – numerous pinhole sized leaks were discovered on one of the Endeavour’s engines during post-flight checkouts at the engine refurbishment facility at the Kennedy Space Center.

These pinhole sized leaks were discovered after Discovery’s liftoff and were thus not part of the STS-128 pre-launch discussions.

Upon examination of Discovery’s main engines during her stay at the Dryden Flight Research Center, over 200 pinhole sized leaks were also observed on one of her engines.

Around the time of the inspection of Discovery’s engines, program engineers found what they believe to be the root cause of the leaks: corrosion due to adhesive tape from standard processing.

In all, engineers will perform several tests and analyses to ensure that the “corrosion mechanism is understood.”

Right now, these leaks are not considered to be a show-stopper for STS-129 next month as it is believed that even the worst case leakage from this issue would not cause “significant performance impacts” during the ride uphill.

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.

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ET-132 Pre-Flight Performance:

STS-128′s ET-132 In-Flight Anomaly (IFA) review by MAF - available for download on L2 - reveals that all ET-132 systems performed nominally during the pre-launch and countdown campaigns for STS-128.

During the three tanking cycles performed on ET-132 during STS-128′s multiple launch attempts, the GUCP (Ground Umbilical Carrier Plate) and related ET and Ground Support Equipment hardware performed as expected, with no abnormal or out-of-spec leaks detected.

The IFA presentation notes that the launch vehicle was exposed to “light rain during final inspection” on the day of actual launch; however, this rain was well within limits set by NSTS (National Space Transportation System) safety and control standards.

During Final Inspection checks following LH2 (Liquid Hydrogen) and LO2 (Liquid Oxygen) cryo-loading, a crack on the -Y Vertical Strut Fairing TPS (Thermal Protection System) was identified. This crack was analyzed by launch team personnel and the Mission Management Team, with the ultimate decision being that the crack was acceptable for flight.

Similarly, frost on the LH2 Aft Manhole Cover Closeout and LH2 Feedline were also cleared for launch, as was “froth” noted on the LO2 Feedline outboard base fitting closeout XT1623.

Furthermore, the presentation notes that both of STS-128′s post-tanking scrubs were not the result of a problem with the tank. The first launch attempt was scrubbed because of weather violations with the second scrub being called due to a problem with the PV-12 inboard fill and drain valve on Discovery herself.

ET-132 Post-Flight Performance Review:

Overall, ET-132′s flight performance can be classed as excellent based on the MAF IFA presentation.

According to the preliminary look at ET-132 based on post-ascent imagery from Discovery’s ET Umbilical Well camera, ET-132 observations are “Consistent with performance expectations; no observed losses on Intertank acreage similar to ET-131; no observed losses related to tensile test repair (Pull Tests),” notes the IFA presentation.

Furthermore, all Protuberance Air Load ramps and Aft hardware performed nominally; all LH2 Ice Frost Ramps (IFRs) were intact, as were all LO2 IFRs which only sustained nominal popcorning/charring/erosion as a result of ascent loads and temperatures.

Also, all Orbiter/ET separation and ET disposal events were nominal, as were ET Structural Systems and Electrical and Propulsion Systems.

Nonetheless, the most rewarding aspect of ET-132′s performance for the dedicated engineers at MAF is the lack of Intertank foam liberation – as well as the lack of foam liberation overall.

Well over 100 Pull Tests of ET-132′s Intertank foam were conducted during the tank’s stay in the Vehicle Assembly Building and at Pad-39A. Those Pull Tests revealed positive adhesion margins of the TPS foam to the tank’s underlying structure.

Based on Umbilical Well imagery obtained by a camera and flash system installed on one of the ET Umbilical Wells of orbiter Discovery, “ET-132 did not demonstrate ET-131 (STS-127) like issues with respect to debris formation or failure modes,” notes the MAF IFA presentation.

Furthermore, in light of recent LO2 IFR liberations (seen on STS-125 and STS-127), STS-128 debuted a modified +X maneuver designed to increase Discovery’s lateral translation over the ET after separation.

The new +X maneuver resulted in a 20-second firing of Discovery’s aft RCS thrusters instead of the previously approved 11-second firing that has been performed for several previous flights.

As a result of this modified +X maneuver, Discovery was eight feet closer to the ET during her pass over the LOX portion of the tank.

This allowed imagery analysts to have sharper images at their disposal during post-launch analysis.

This closer pass allowed clear and more detailed resolution of the bi-pod and LOX tank of ET-132, allowing imagery analysts to determine that no adverse erosion or liberation of the LOX IFRs occurred during Discovery’s ascent.

Furthermore, the +X maneuver images, as well as images from the onboard SRB engineers cameras, revealed only five areas of ET TPS damage/liberation, making this the cleanest External Tank in terms of foam liberation in the history of the Space Shuttle Program and highlighting the supreme work by all MAF and KSC workers involved in processing the External Tanks for flight.

In all, one of the TPS liberations was discovered of the LH2/Intertank Flange closeout, two on the ET Bipod area, and two “outside of the debris zone on the -Y/-Z thrust panel” of the Intertank.

Based on images/video obtained from the SRB engineering cameras and the ET Umbilical Well camera, the LH2/Intertank Flange foam liberation event occurred after SRB separation and contained a maximum mass of ~0.040 lbs.

MAF has determined the failure mode for this liberation as “cryo-ingestion.”

This foam loss exceeds the allowable mass limit set by the NSTS 60559 safety rule. As such, this foam liberation has been identified for inclusion into the STS-128 Integration In-Flight Anomaly review.

As such, MAF is recommending an update the NSTS 60559 table risk assessment for “LH2/Intertank Flange for Cryo-ingestion” to update the table for failure modes “in accordance with flight history, debris cloud, and debris expectation.”

As for the two Bipod foam liberations, they occurred on opposite sides of the Bipod closeout.

The first, occurring on the -Y Bipod closeout had a mass of ~0.001 lbs and was caused by either a “Void delta P, or cryopumping/ingestion.” The exact time of release is unknown, though its mass would not have posed a hazardous risk to Discovery’s TPS regardless of its liberation time.

The second Bipod foam liberation, occurring on the +Y Bipod closeout, had a mass of ~0.005 lbs. Like its counterpart on the -Y Bipod, the +Y Bipod liberation time is unknown and was likely caused by “Void delta P, or cryopumping/ingestion.”

The final two foam liberations from ET-132 occurred on the -Y/-Z side of the tank near the GUCP on the thrust panel of the ET.

The mass of these pieces was estimated to be 0.003 lbs with a release time of ~123-seconds (2-minutes 3-seconds) into flight.

The primary liberation cause was determined to be either popcorning/Void delta P/or crush.

These liberations were outside of the critical debris zone and are thus not a concern for Orbiter TPS damage.

Overall, ET-132 performed exceptionally well, a true testament to the care and dedication of the MAF workers in Louisiana.

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.

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STS-128 Ferry:

Discovery was mated to the SCA on Friday evening at the Dryden Flight Research Center (DFRC) before departing at 12:23 EDT for a refueling stop in Amarillo, Texas. A short hop over to Fort Worth followed, prior to the final journey of the day to Barksdale Air Force Base – landing at 1839 EDT Sunday night.

Planning for final leg required evaluations into unsettled weather over the flight path, before clearance was given not long after the scheduled departure time. With the NASA Pathfinder aircraft flying ahead, the best route back to Florida was picked for the SCA/Discovery duo, as they crossed over into Florida around 11am local time.

The duo landed on the Shuttle Landing Facility (SLF) at around noon time, after a decision was made to cancel a flyaround of KSC due to poor weather closing in on the region.

The rest of the day involves demating Discovery from the top of the SCA at the Mate/Demate Device (MDD) located at the end of the SLF. Once raised off the SCA, the converted 747 will reverse clear, prior to Discovery being lowered on to her wheels for the tow back to her Orbiter Processing Facility (OPF).

Inside the home comforts of the OPF, Discovery will undergo further safing and post flight inspections – picking up on the procedures that began at Dryden.

She will then head into her next flow, for the March 18, 2010, STS-131 mission – which will involve the delivery of supplies to the International Space Station (ISS) via the Multi-Purpose Logistics Module (MPLM) Raffaello and the Light-weight Multipurpose Experiment Support Structure Carrier (LMC).

A full review of her highly successful mission to the ISS is set to take place this Thursday, when the Program Requirements Control Board (PRCB) carry out the IFA (In Flight Anomaly) review – a required meeting which will also play a part in both the next scheduled shuttle mission (STS-129) Flight Readiness Review (FRR) and Discovery’s downstream STS-131 mission FRR.

STS-129 Processing:

Discovery joins her two sisters at KSC, both processing for their downstream missions. Atlantis is due to launch next, with her STS-129 mission to the ISS – set to deliver the Express Logistic Carriers 1 and 2 (ELC-1 and ELC-2) to the Station – due to take place in mid-November.

Atlantis is currently undergoing closeouts – with recent issues relating to her Orbiter Docking System (ODS) now cleared – as her External Tank (ET-133) and the twin Solid Rocket Boosters (SRBs) undergo mating operations on Monday inside the Vehicle Assembly Building (VAB).

“Orbiter closeouts continue. Cabin air recirculation inspection and maintenance was completed on Saturday. Orbiter electrical bus redundancy checks were completed,” noted Monday processing information on L2. “ODS closeouts and centerline camera adjusts are complete. PV-9 (Fill and Drain Valve) borescope inspections are complete.

“ET-133 (VAB HB-2) Preps for ET Mate are complete. SRB/RSRM BI-140 / RSRM 108 (VAB HB-1): All joints closed out and platform retractions are in work. ET/SRB Mate scheduled for today (Monday). Hook Down is scheduled for 0800.”

As noted in the processing update, inspections on Atlantis’ Fill and Drain Valves have been carried out, following issues with indications on Discovery’s LH2 PV12 valve during STS-128′s August 26th launch attempt.

The LH2 Inboard Fill and Drain Valve 50V41PV12 (PV12 for short) is located in the orbiter’s Main Propulsion (Liquid Hydrogen) System inside the Aft Fuselage of Discovery. These 8-inch internal diameter Bi-Stable Pneumatic valves are classed as Criticality 1 hardware.

There are four of these valves inside the MPS (Main Propulsion System), with the LO2 system housing the PV9 LO2 Outboard Fill/Drain Valve and PV10 LO2 Inboard Fill/drain. The LH2 System houses the PV11 LH2 Outboard Fill/Drain and the failed PV12 LH2 Inboard Fill/Drain.

The requirement for the nominal operation and cycling of the valve mainly relates to the ability to offload propellant in the event of – for instance – a pad abort, where detanking needs to take place in a timely manner. Offloading could still occur via the alternate PV11 route, but would take twice as long – which would be undesirable.

While the issue failed to repeat itself during the next launch attempt – and performed nominally – engineers are checking the valves on Atlantis to confirm the issue is not related to identical valves on the fleet.

“Inspection of the MPS fill-and-drain valves was performed,” added engineering notes. “For PV9 and PV11, the valve-position indicator is under evaluation by Engineering.”

The PV12 valve on Discovery will be replaced during her STS-131 flow, which was pre-scheduled due to the valve reaching the end of its operational lifetime.

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.

No related posts.

Pre-departure Processing:

Discovery had no issues during her processing flow at the Dryden Flight Research Center (DFRC) – located in the grounds of the Edwards Air Force Base (EAFB) – and was almost on track to depart as early as last Friday.

However, weather along the flight path was unacceptable, leading to an extended stay in California ahead of the Sunday morning departure.

Most of the final processing surrounded the final checks to Discovery’s Thermal Protection System (TPS) at the Mate/Demate Device (MDD) – as the orbiter was raised in order to allow the SCA to roll underneath for mating.

“Orbiter: OV-103 / Edwards AFB Turnaround Operations Post landing operations continue: TPS status for ferry: RSB (Rudder Speed Brake) thermal barrier – trimmed and coated. Flexible insulation blanket on right OMS (ROMS) – trimmed and coated,” noted the final processing notes on L2 ahead of her departure.

“Gap fillers on ROMS leading edge – no access – fly as is. FRSI plug on ROMS – no access – fly as is. Cracked tile on RSB – fly as is.

“Tail Cone and fairing installation is complete. Final hydraulic operation to raise the landing gear and position the bodyflap is complete. Side Access Platforms are up. Orbiter lift and mate to Shuttle Carrier Aircraft (SCA) completed.”

The smooth processing at Dryden also earned praise from Space Shuttle Program (SSP) manager John Shannon on the latest Shuttle Standup/Integration report (L2) – who also hinted at the potential of flyovers of NASA centers during the trip back – as much as that would depend on the weather.

“Mr. Shannon stated that he is really proud of the team that is working at Dryden. The work is progressing well. This is a hazardous operation, so everyone must keep their eye on the ball. Whether we are able to have any fly-overs of the NASA sites during the ferry-flight back to KSC will be dependent on the weather. If we are able to work it in, we will.”

With thousands of spectators reported at the landing sites, the SCA and Discovery failed to take an optional fly-by of the Johnson Space Center (JSC), likely due to poor weather on the required flight path.

Pre-Ferry Flight Readiness Review:

As with all missions, the Flight Readiness Review (FRR) ensures all resources are in place in the event of a Californian conclusion to a mission. For STS-128, the review was conducted in August.

“The STS-128 Ferry Planning Readiness Review was conducted on 8/5/09. No issues were identified. If a ferry flight is required, a Ferry Flight Readiness Milestone Review will be conducted one day prior to the planned start of the ferry flight,” noted the SSP FRR presentation (L2) relating to Ferry readiness.

“Hardware summary: Orbiter: OV-103 (Discovery). NEOM ferry weight and center of gravity: 228,507 lb Xo 1113.7 in Yo 0.0 in Zo 374.7 in NEOM mass properties are within specified limits 3516 lbs of crew module ballast required (2066 lbs of middeck ballast kit hardware plus 1450 lbs of additional middeck equipment).

Both of NASA’s SCAs were classed as ready to support, though a final decision resulted in SCA 911 being used, as opposed to NASA 905. Both SCAs were on site at Dryden.

“Attach hardware and ferry plugs are ready to support. Tailcone 1 is assembled at DFRC and ready to support. Shuttle Carrier Aircraft (SCA): NASA 905 is at DFRC and expected to be ready to support (scheduled for a functional check flight at the end-of-the-month). NASA 911 is also at DFRC and ready to support. Pathfinder: NASA 932 (C-9),” added the FRR presentation.

“For a ferry flight beginning in September, purge equipment will not be deployed. A USAF aircraft (KC-135 or C-130J) could also be used. Ferry flight requirements are current: Ferry flight configuration drawings have been released. DFRC seven day turnaround with ready-to-ferry the morning of day eight.”

Special requirements were also listed for the payload that Discovery still has in her cargo bay, namely the Leonardo Multi-Purpose Logistics Module (MPLM). While all of its logistic supplies were transferred during Discovery’s mission to the International Space Station (ISS), the MPLM is returning a large amount of downmass from Station.

“The MPLM shell heaters will be enabled during ferry flight and at stopover locations when the ambient air temperature is less than 70 degrees F. This purpose of this requirement is to protect the MPLM structure against condensation,” the FRR presentation continued.

“There is a standard requirement to provide a purge to the forward and aft RCS (Reaction Control System) if the ambient air temperature is predicted to be less than 45 degrees F (mitigates the potential for RCS thruster leakage). There are no payload purge requirements.

“Adequate airfields are available to support ferry operations. Prime landing sites, weather alternates, and emergency landing fields selected. Flight plan: The nominal flight plan is for four flight legs that will be flown over 2-days.”

More will follow shortly.

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:

1. Endeavour’s cross country ferry trip moved to at least WednesdayEngineers are continuing to prepare Endeavour for her trip back...
2. Endeavour and her SCA piggyback ride arrive in Louisiana, via JSC flyoverThe Shuttle Carrier Aircraft (SCA) and Endeavour departed from Edwards...

STS-128/Dryden Latest:

Discovery may depart from the Edwards Air Force Base – home of the Dryden Flight Research Facility (DFRC) – as early as Friday, pending a smooth processing flow at the Mate/Demate Device (MDD). The only issue encountered so far related to a lift platform that required repair.

“OV-103 (STS-128/STS-131): Orbiter turnaround operations continue in California. Continuing to work aft access,” noted the latest Shuttle Standup/Integration report on L2.

“Had some issue with high winds; are down 12 hours (contingency) overall, and (had issues with) the Aerial lift platform (Condor) – worked a couple of other options in case that didn’t work in a timely fashion. Still scheduled to start the ferry flight back to KSC this coming Friday.”

With the platform soon repaired, work was proceeding at a good pace throughout Tuesday.

“Orbiter: OV-103/Edwards AFB Turnaround Operations: Post landing operations are in work. SSME (Space Shuttle Main Engines) drying operations were complete on Monday. Cryo offload is complete; PRSD (Power Reactant Storage and Distributation) tank inerting is complete,” added Tuesday morning processing information on L2.

“AFT access continues; 50-1/2 doors have been removed. Pyro LCA boxes 1, 2 & 3 are mated. Baggie leak checks are complete. QD (Quick Disconnect) Mates for OMS Ball Valve Cavity Drain are complete. Fuel Cell Repressurization and Inerting complete.

“Fuel Cell Repressurization and Inerting complete. 44 door removal is in work, having trouble removing one fastener. Condor issues have been resolved. It is in position and in use. All plugs in the ‘crotch’ area, left and right, have been installed.”

As with Atlantis’ STS-125 mission, which was the previous mission to conclude in California, Discovery’s Flow Control Valves (FCVs) have already been removed from the orbiter’s Main Propulsion System (MPS) to head their fabricator “Vacco” – who are based on the West Coast.

“Flow Control Valves are removed and purge plugs have been installed. Flow Control Valves will ship to VACCO,” confirmed the Standup report, which will allow for timely inspections for any signs of cracks, prior to their reuse in a downstream mission.

Click here for NASASpaceflight.com articles on the FCV issue since STS-126.

TPS (Thermal Protection System) Ferry flight inspections are also complete, aided by the clean flight of Discovery that resulted in only a handful of minor ‘cosmetic’ areas of damage during her mission – as reported on Monday via the runway report.

“The runway TPS Quick Look is out. The report indicates that overall the vehicle looks good. There were only around 15 tiles that had damage of >1”, which is good,” the Standup report continued. “The Boundary Layer Transition (BLT)-2 withstood the flight well also. There was no visible slumping. On the catalytic coating experiment, got a mixture of black color flaking, so the team will have to access it.”

“On the BLT DTO (Detailed Test Objective), looks like it tripped at Mach 18,” added the Orbiter Project at the Johnson Space Center. “For the High Thermal imagery, it looks like the Mach number at closest approach was 15 or 16. The long-range acquisition data was estimated at Mach 19.”

With all the initial inspections confirming an issue-free mission – from launch to landing – Mission Management Team co-chair LeRoy Cain praised the team for an outstanding effort.

“Friday was a great finish to an outstanding mission, just a beautiful landing out at Dryden. Folks are working hard on getting Discovery turned and prepared for the Ferry Flight. Looking forward to getting her back to the Cape,” Mr Cain added to this week’s Standup report.

“Congratulations to the whole team on an outstanding mission. It was a wonderful effort from beginning to end.

“We are well on our way towards getting ready for STS-129. It looks like everybody is chugging right along. Great job! If you did not get a chance to do so yet, take a little time off now that we have the crew back safely and before we get too far into the thick of preparing for STS-129. Appreciates the great effort. We are really on track.”

STS-129 Processing Latest:

Atlantis returns to ISS missions – following her flagship mission to service the Hubble Space Telescope for a final time – with the aforementioned STS-129 mission, set to deliver the Express Logistic Carriers 1 and 2 (ELC-1 and ELC-2) to the Station.

The launch date – currently in early to mid November – remains under evaluation due to several conflicts, including with the Russian launch schedule. An article on the issues will follow this week, as a November launch may not be viable.

For now, Atlantis remains on track to meet her processing milestones, with the mating of her twin Solid Rocket Boosters (SRBs) and External Tank (ET-133) due to take place next Monday inside the Vehicle Assembly Building (VAB).

“In VAB, have completed SRB stacking over the weekend. Into joint closeouts. Target is to mate the ET next Monday. On ET-133, last week completed all the backscatter X-rays. +Z Plug pulls are complete and repairs are in work. Of the 48 pulls had 1 location with an “adhesive failure” and 3 “low PSI value” locations. Lockheed Martin has data for analysis.”

On the tanks, the evidence continues to point to a one-off issue with ET-131, when several areas of its intertank liberated during Endeavour’s ascent, likely caused by a dust-related contamination issue during its foam application at the Michoud Assembly Facility (MAF).

With the successful plug pulls on ET-132, and no major issues reported so far with ET-133 – with only the one adhesive failure out of 48 pulls reported – the tests are classed as due diligence being carried out on the next tank to fly, in order to ensure nothing has been missed ahead of flight.

As a result, it is unlikely managers will call for a similar amount of plug pulls that were conduced on ET-132 – which saw hundreds of tests being carried out both in the VAB and out at Pad 39A, in order to satisfy the Flight Readiness Review (FRR) level investigation into STS-127′s foam liberation events.

With Atlantis herself, the only main issue during her recent flow came via the re-installation of the Orbiter Docking System (ODS), which wasn’t required for STS-125′s mission to Hubble.

The problem came during testing, when the ODS ring did not stop after reaching the ‘Initial’ position (76 percent extended) but continued to drive further. Engineers had to call for emergency stop at 88 percent extend for troubleshooting.

“Troubleshooting was performed and they were unable to re-create the problem. Telecons were held with Energia (contractor of the Russian Space Agency) and the technical community,” added a communication between engineers and Shuttle manager John Shannon.

“The most probable cause is most likely a sticky push button on the APDS (Androgynous Peripheral Docking System), but we headed down the UA (Unexplained Anomaly) path. We ran the ODS (with the suspect APDS) through several tests after the initial failure and it has performed nominally.”

With the APDS panel replaced, functional tests – conducted infront of Russian experts that were flown into Florida – were successful. However, a new issue with the system was reported at the end of last week.

“Last week, did ODS (Orbiter Docking System) upper hatch pressure dome leak check; that failed,” added the Standup report. “Have changed out the upper hatch and collar seals; are in a 72-hour cure. Later this week will pick back up with the pressure dome leak check.”

Processing is continuing with orbiter closeouts, retests and leak checks inside Atlantis’ Orbiter Processing Facility (OPF-1), as outlined in the latest flow updates.

“OV-104 (STS-129): Over the weekend, started CEIT (Crew Equipment Interface Test). Picked up a few minor squawks (issues),” noted the Standup report. “SSME gimbal checks, and SSME leak checks (completed). Picking up camera checkout. Completed cabin leak check over the weekend.”

A cabin pressure leak check decay rate was deemed to be too high during testing, but was soon resolved. “Troubleshooting found a vent line was open. The line was capped and system passed retest.”

“SSME TVC (Thrust Vector Control) and caution and warning checkout was completed with nominal results. Bodyflap PDU leak checks were completed and aerosurface positioning followed,” the flow update on L2 continued. “RCS (Reaction Control System) vernier heater checks (picking up). OMS closeouts will pickup Wednesday and run through the week.

“WLE (Wing Leading Edge) flight battery installation and end-to-end testing picked up Monday and continues through Wednesday.”

STS-130 Processing Latest:

The first of five scheduled missions in 2010, Endeavour’s STS-130/20A flight will deliver and install the final US module to the ISS. This module, the Node-3 and adjoining Cupola unit, is currently undergoing processing for flight in the Space Station Processing Facility (SSPF) at KSC.

Endeavour, processing in OPF-2, is deep into her STS-130 flow, following her return from the highly successful STS-127 mission which delivered the final piece in the Japanese jigsaw on Station.

“MPS (Main Propulsion System) flowliner inspections continue in work. Picking up with preps for FRCS (Forward Reaction Control System) installation,” noted a Standup level report overview of processing. “The FRCS will be coming up in the HMF (Hypergolic Maintenance Facility) this week; will install this coming Saturday.”

Endeavour’s flow was expanded on during the latest daily processing update, which listed no issues in work for the youngest orbiter in the fleet.

“Fuel Cell 2 R&R picked up on Monday and is continuing. The old fuel cell 2 has been removed from the orbiter and installed into its shipping container. MPS 12in flow liner inspections are continuing. Water Spray Boiler (WSB) checkout and servicing picked up Monday and is continuing.

“Window 7 removal was completed Monday and new window installation is in work. Hydrogen separator R&R began Tuesday. APU (Auxiliary Power Unit) leak checks and GN2 QD heater functional picked up Tuesday. LOMS engine GN2 relief valve functional is scheduled to pick up on second shift Tuesday. ROMS engine GN2 relief valve functional is planned for Wednesday.”

Marking a busy flow for the fleet, the next set of SRBs are being built up in the Rotation Processing and Surge Facility (RPSF), waiting their turn to be stacked on a Mobile Launch Platform (MLP), while STS-128′s booster mating with the ET takes place.

“SRB/RSRM BI-141/ RSRM 109 (RPSF): Right Aft Booster Build-up. RT-455 Application to Stiffener Rings is complete. Aft IEA Installation. Task is ready-to-work after PDL repair on ETA ring insta-foam,” added processing information.

“ETA Ring Instafoam Application. Pull test is complete and acceptable, less the Aft side of the ETA ring at the 34 Degree location. Instafoam removal at 34 Degree location is in work. Strut And Receiving is complete. Extender Cable Installation in the ETA Ring is complete. Systems Tunnel Cable Installation. Task is ready-to-work after Instafoam R&R.”

Their partner, ET-134, will soon ship from MAF – with the New Orleans facility enjoying a smooth flow on all its downstream tanks, an achievement that is often overlooked when considering the fight back they have made since Return To Flight and the horror of Hurricane Katrina.

“ET-134: Everything is going nominally for test/checkout activities in Building 420,” was all MAF needed to report on the Standup, with ETs 135 through 138 all on schedule for their downstream shuttle missions.

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.

No related posts.

STS-128 Post Flight:

Discovery is undergoing safing at the Mate/Demate Device (MDD), which will be used to eventually raise Discovery to allow the Shuttle Carrier Aircraft (SCA) to roll underneath for mating.

The date for the duo’s trip back to the Kennedy Space Center (KSC) has not yet been set, but should follow a schedule – pending an issue-free flow – that will result in a weekend departure for the several legs of their cross country journey.

For the meantime, Discovery is being safed at the MDD, which involves the opening tasks relating to the removal of the hazardous hypergolics that require purging from her systems.

“Orbiter: OV-103 / Landing – Edwards AFB Turn Around Operations: Discovery safely landed on Runway 22 at DFRC at 2053 EDT following a very successful mission. Post landing operations are in work. SSME (Space Shuttle Main Engine) Drying operations are complete. ET sep camera has been removed,” noted Monday processing information on L2.

“OMS (Orbital Maneuvering System) trickle purge is active. Cryo offload is complete; PRSD (Power Reactant Storage and Distributation) tank inerting is in work. AFT access continues; 50-1 / 2 doors have been removed.”

Upcoming tasks include the retraction of her landing gear, once she has been raised off the ground by the MDD.

STS-128 TPS Evaluation:

Thanks for a superb performance from Discovery’s External Tank (ET-132), the amount of damage to the orbiter’s TPS was observed to be extremely small. That assessment has been backed up by the condition of the TPS via the runway report – which is the opening hands-on evaluation carried out post flight.

“General: TPS assessment began at 7:22 pm PDT (Total Downgrade at 7:18PDT). Overall the vehicle looked good,” noted the Runway report – acquired by L2. “Approximately 15 tiles had damages greater than 1.0 inch. There were no protruding Ames gap fillers identified.

“Forward Section: NLGD (Nose Landing Gear) thermal barriers appeared nominal. NLGD RTV residue on the tile OML surfaces, observed on orbit, was still visible post landing.

“V070-399441 chin panel gap was 0.10” right, 0.15” center, and 0.10” left. No frays or tears were observed in the chin panel gap filler other than the 1” breach cleared from the prior flight. It did not tear any further. The gap filler was adhered to the nose cap side of the gap over its entire length.”

One of the few items of interest noted by the Damage Assessment Team (DAT) via the Flight Day 3 RPM imagery pointed to a protruding sleeve on the Arrowhead section of the orbiter. This failed to grow in size during re-entry.

“Nosecap and chin panel RCC appeared nominal. Arrowhead blanket sleeving protruded over a 1.7” length with a maximum height of 0.25” as observed on orbit,” added the report.

“Midsection: MLGD (Main Landing Gear) thermal barriers appeared nominal except for symmetrical tears in the OML fabric at the forward outboard corner of both doors. Each side had OML fabric torn approximately 1.5 inches in length..

“RCC (Reinforced Carbon Carbon) WLE (Wing Leading Edge) appeared nominal. No red/orange residue was seen on the RCC panels.”

Of the small amount of tiles that did suffer damage during the ride uphill, all are deemed only as “cosmetic” coating loss, and none saw an increase in the area of damage during re-entry. One area was noted as new damage, but could have been caused during Discovery’s rollout post-landing.

“ET door thermal barriers appeared nominal. Tile damages outboard of RH ETD (Right Hand ET Door) appeared unchanged from on orbit imagery: (Several Tiles) with coating only damage approx 1.5 x 0.5 x 0.1” deep,” added the report.

“Tile damages outboard of LH (Left Hand) ETD appeared unchanged from on orbit imagery. Tile damage not identified by on orbit imagery aft of LH ETD in tile V070-395037-046, approx 1.0 x 1.0 x 0.25” deep. Additional peppering was present on approx 10 tiles further inboard of the -046 tile.”

The first post flight images of the two areas relating to STS-128′s re-entry Detailed Test Objectives (DTO) were also provided in the report.

Firstly, the Boundary Layer Transition (BLT) Detailed Test Objective (DTO) - which is one of a series of tests to measure the effects of increased heating from an early boundary layer transition as the orbiter returns to Earth – is shown to be in good condition.

Two areas of cosmetic damage were observed via the RPM imagery, though they held no constraints to the results as they were either side of the BLT DTO protruding tile, as opposed to downstream of the heat flow.

“Damage sites observed on orbit on either side of BLT tile appeared unchanged relative to on orbit photos (V070-191011-113, -118, -119 and V070-191012-043). The maximum depth on these damages was 0.2”,” added the report.

The catalytic coating DTO – which involved two tiles in the turbulent heating wedge on the belly of Discovery being coated with a fully catalytic (CC-2) coating – will provide additional aeroheating data for both Shuttle and Orion.

The two green stripes seen during pre-flight photography are no longer visible, bar their outlines and a slight amount of flaking on one of the two tiles involves with the test.

“Catalytic coating on tiles V880-191011-007 and -015 was a dull black color. The coating on the -007 tile was in good condition with no obvious flakes. The coating on the -015 tile was crackled and was flaking on the trailing edge of the coated area.”

Other areas will be checked either later in the flow, or once Discovery is back in her Orbiter Processing Facility (OPF), where additional access for engineers is available.

“Protruding FRSI plug RH OMS pod could not been seen from the runway frayed gap fillers on LH IB OMS pod could not be seen from the runway,” added the report referencing the aft of the vehicle, which included good news on the SSMEs and associated aft TPS.

“Engine 1 dome heat shield blanket a minor tear at the lower splice line (6 o’clock position). No piano key tiles were deflected downward, however tile 395018-145 had a damage on the trailing edge inboard corner. The rudder speed brake split line trailing edge thermal barrier on the right hand side was blown out.”

Normally, areas of damaged TPS would be repaired as best as possible ahead of the SCA flight back to Florida, so as to avoid additional damage during the ferry. However, given the excellent condition of Discovery, it is unlikely any such work will be required.

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.

No related posts.

STS-128 Return:

Discovery allowed managers to concentrate on the weather conditions by continuing to perform in an exemplary manner on orbit, with no new issues noted on the Mission Evaluation Room (MER) list of “funnies”.

With two attempts to land back at her home base of the Kennedy Space Center both called off on Friday as the weather conditions were deemed to be even worse than Thursday’s landing waved off opportunities.

With no sign of improvement, Flight Controllers at the Johnson Space Center (JSC) made an early decision to switch their attentions to landing Discovery at the Californian home of the Dryden Flight Research Center (DFRC),

Now on the ground, Discovery will undergo safing over the weekend, prior to lifted up on the Mate/Demate Device (MDD) for work on her landing gear and propulsion systems – notably the hypergolic systems – along with the installation of the tailcone, which will protect the aft of Discovery during the mated trip cross country on top of the converted 747.

The veteran orbiter’s performance has mirrored the vast majority of the flights over recent years – which earned praise from Space Shuttle manager John Shannon.

“The entire team has done a tremendous job during this flight. It could not have gone any better!” Mr Shannon noted on the latest Shuttle Standup/Integration report on L2. “This is exactly how we want to complete the remaining flights.”

A return to California holds no impact to the Boundary Layer Transition (BLT) Detailed Test Objective (DTO) observations, with the Hypersonic Thermodynamic Infrared Measurements (HYTHIRM) team making the right choice to assume Discovery would be heading to California.

With the HYTHIRM aircraft in position over the Pacific Ocean, Discovery’s return was monitored in close detail, as the heatshield on the vehicle rode through re-entry.

“In the absence of any constraints (ground track, weather, Shuttle orientation, aircraft capability) what is the recommended Mach number (point of closest approach)? Mach 16.5 Maximize science: Anticipate fully developed turbulent flow behind the wing protuberance at this Mach number,” noted a Program Requirements Control Board (PRCB) presentation associated with STS-125′s results - dated Thursday, and available on L2.

The presentation also noted the slight cosmetic damage that was observed near the vicinity of the DTO via Thermal Protection System (TPS) surveys, ahead of docking with the International Space Station (ISS).

As noted by the DAT (Damage Assessment Team), both areas of damage are not in the downstream path of the tile protrudance, with the HYTHIRM confirming they expect no interference.

“Will observed tile damage influence observation? Unlikely that turbulence from STS-128 TPS damage will obscure our view of the DTO wedge at Mach 16.5,” added the PRCB presentation. “No change to recommendation for Mach 16.5 HYTHIRM deployment.”

This DTO will see an increase in the Boundary Layer Transition tile to 0.35″ during processing towards Discovery’s next flight – STS-131 – based on performance data from STS-128.

The goal of the experiments is to measure the effects of increased heating from an early boundary layer transition as the orbiter returns to Earth. The DTO was set to debut on STS-126, before being deferred to STS-119.

Discovery is also debuting another entry-related DTO on behalf of Orion. A “Catalytic Coating” was applied to two of Discovery’s Thermal Protection System (TPS) tiles, providing Orion – and shuttle – engineers with refined aeroheating data.

STS-131:

Currently targeting launch on March 18, 2010, Discovery’s STS-131 mission will deliver supplies to the International Space Station (ISS) via the Multi-Purpose Logistics Module (MPLM) Raffaello and the Light-weight Multipurpose Experiment Support Structure Carrier (LMC).

Initially, Discovery was to begin processing for STS-131 on August 31. However, due to multiple launch date delays due to External Tank foam concern, weather, and a fill and drain valve, Discovery did not launch until August 29.

Should Discovery land in Florida on Friday, processing for STS-131 will begin once initial safing and excess propellant is offloaded from the vehicle in OPF-3 (Orbiter Processing Facility Bay 3).

However, should Discovery land in California, full-up processing for STS-131 will not being until the Orbiter has been flown back across the country — a task that usually takes between nine and ten days to accomplish following a landing at Edwards Air Force Base.

Nevertheless, Discovery’s flow toward STS-131 is longer than the usual OPF flow — ~145-days v. the minimum ~100-days a vehicle can be processed out of the OPF.

During her stay in OPF-3, Discovery will have her #2 APU (Auxiliary Power Unit) — one of three devices (APUs) that provide hydraulic power to the vehicle during launch and entry — replaced due to time and cycle requirements.

Additionally, Discovery’s Main Propulsion System PV 9 and PV 12 fill and drain valves will be replaced for the same reason — as both of these valves have reached the end of their 16 flight certified lifespan.

It should be noted that this replacement was scheduled well before the PV-12 valve sensor malfunction occurred on the launch pad on August 25 — a malfunction which caused a scrub to Discovery’s 2nd launch attempt.

However, the first of several modifications that will be made to Discovery during her turn-around flow will be a the implementation of a redesign to the Rudder Speed Brake (RSB) Inconel Thermal Barrier tabs — tabs which provide thermal protection from the SRB and main engine plumes during ascent.

Stemming from a liberation event on Discovery’s STS-124 mission in June 2008, the modification of the RSB tabs “provides redesigned (RSB) inconel thermal barrier tab attachments to improve strength and durability,” notes the STS-131 Launch Site Flow Requirements presentation, available for download on L2.

For the modification, all 60 tabs located on the RSB periphery will be replaced.

An initial modification was made to the tabs following STS-124. However, that modification did not work as several tabs were found missing on the following mission (STS-126) during post-flight inspections of Endeavour in December 2008.

For this modification, the fastening mechanism will be improved by increasing the number of “spot welds,” shortening the overlap of each tab to 0.300,” and adding a secondary fastener via an increase in tab length.

The next modification discussed in the LSFR is to the Starboard Lightweight Tool Stowage Assembly (TSA).

“Due to allocation of the two standard port lightweight TSAs to OV-104 (Atlantis) and OV-105 (Endeavour) and manifest delays, OV-103′s (Discovery’s) STS-128 flight required use of the starboard LWT TSA for stowage of standard contingency tools,” notes the review document.

To accommodate this need, a new cushion was provided. This will allow the tools to be stowed in the starboard TSA; however, a fit check issue has yielded a one flight modification to “reverse the forward tool tray installation and remove its handle.”

The orientation of the TSA to the upside-down position was necessary in order to properly mount the TSA to the Starboard location.

This reversal now places the tray handle on the bottom. As such, the handle had to be removed to allow the tool tray to fit properly and allow the TSA lid to close. The handle will be relocated to the opposite end of the tray to place it in the proper position for the starboard TSA.

The final approved modification at this time “Improves the damage resistance of the Aft Stub carrier panel tiles adjacent to the body flap” of the orbiter — which is parallel to the three Space Shuttle Main Engines.

Historically, several damage locations in this area of the vehicle have been attributed to ground processing procedures.

As a result of this realization a few years ago, eight tiles in the area were upgraded to reduce the risk of damage associated with ground processing.

However, recent tile damage in this area has been seen on the tiles that were not modified. Furthermore, flight experience has shown that the tiles that were upgraded have performed very well.

As such, the remaining tiles in this region will be upgraded for STS-131 and subsequent flights. This new material will have approximately twice the strength of the previous material.

In addition to these modifications, several other configuration changes are under review for STS-131.

Among these are a redesign of the Gaseous Hydrogen Flow Control Valve poppet following the event seen on STS-126, a redesign of the F3D/F4D thruster cover, a sneak peak of the Wing Leading Edge spar inspections, a redesign of the Wing Leading Edge Carrier Panel Horse Collar Gap Filler on panels 1-4, and a connector saver redesign of the OMS Pods and Ku-Band Antenna.

Click here for NASASpaceflight.com articles on the FCV issue since STS-126.

Also under evaluation for the STS-131 are the delivery dates for Government Flown Equipment and the Flow Control Valves and the potential removal and replacement of the Multiplexer/Demultiplexer due to Wave Form Output.

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.

No related posts.