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 Wednesday Engineers are continuing to prepare Endeavour for her trip back...
2. Endeavour and her SCA piggyback ride arrive in Louisiana, via JSC flyover The Shuttle Carrier Aircraft (SCA) and Endeavour departed from Edwards...

Large crowds and numerous youtube videos of the SCA and Endeavour pairing have marked their trip from Edwards Air Force Base, which took in a brief stop at Fort Bliss’ Biggs Airfield, Texas, before heading for an overnight stay at Fort Worth, Texas on Wednesday.

The second leg ended with another overnight stay on Thursday in Barksdale, Louisiana – following a slight detour via the Johnson Space Center (JSC), where the duo circled the Houston base around five times, providing a stunning sight to workers congregated in the parking lots.

The decision to carry out the flyby of JSC was left to the last minute, so as to ensure acceptable weather conditions in the local area. The event was part of NASA’s 50th Anniversary celebrations, and was the first visit by a SCA/Orbiter duo since Challenger paid a visit to Houston in 1983.

Original plans pointed towards Endeavour and the SCA arriving back at the Shuttle Landing Facility (SLF) on Thursday, before a weather front blocked their path. An overnight stay in Barksdale then became the plan, ahead of the Friday departure that concluded with a landing in Florida in the afternoon.

Meanwhile, Thursday marked the final major engineering overview of STS-126, via the post flight IFA review – which involves the presentation of over 12 documents (all available to download on L2) outlining every aspect of the mission and any noted anomalies.

These reviews range from EVAs to flight software, launch/ascent issues to the performance of the External Tank and so on – most of which will be collated into articles on this site over the next few weeks.

The first issue of note relates to the time of ignition, T-0 – classed as the “Holddown Post (HDP) #3 Debris Containment System (DCS) Failure,” which received references as part of the Solid Rocket Booster IFA review presentation.

There are four holddown posts (studs) on each booster, with each stud 28 inches long and 3.5 inches in diameter.

The stud has a frangible nut at the top end, which contains two NASA Standard Detonators (NSD), which are fired at the time of SRB ignition, breaking the nut and releases the connection between the vehicle and the post.

Interestingly, this was the first launch with the newly modified holddown bolts - first aimed at STS-125, before that mission was delayed until 2009 - although it is not clear if that is related to the incident noted on the IFA presentation.

“Video showed SRB Hold Down Post (HDP) location #3 plunger spring and plunger extended during lift-off. SRB In-Flight Anomaly declared. Anomaly Resolution Team declared,” noted the IFA presentation.

The event, which led to some of the debris from the holddown post liberating away from the containment system – which avoids such debris from potentially striking the vehicle during lift-off – was last seen on the STS-56 launch.

“Determined portions of frangible nut contacted plunger assembly before sealing blast container bore,” added the presentation. ”Contact caused plunger shoulder to fail at flange cut-outs.”

The SRB Blast Container (BC) Debris Containment System (DCS) has the purpose to contain frangible nut debris when the stud travels aft with plunger after frangible nut fractures.

As to where the debris travelled, engineers found parts of the 2.5lb plunger spring in the north flame trench, which highlighted the force that can transport such debris. However, there was no evidence of it travelling towards the vehicle during launch.

“Postflight Pad walk down discoveries found; plunger spring pieces (25 percent of 2.5 lb), NASA Standard Detonator (NSD) with adapter and possible web of frangible nut,” added the presentation.

“Melted metal deposits on stud, lower nut and washer. Stud eroded 0.5 inch in length. Approximately 95+ percent of shoe shim eroded.”

Engineers will carry out a full investigation over the coming week, via the safety board and the all-power PRCB (Program Requirements Control Board), following the establishment of a fault tree established, which may recommend a redesign of the system ahead of STS-119 next year.

“Investigation on-going. Evaluating potential fail-safe design modifications.”

Other items of interest with the boosters – known as “squawks” were listed as “Suspect Sea Water Activated Release (SWAR) Failed to Release x4″ – which has been seen on most recent flights, and is a known issue with no mission impact.

The others are listed as “foreign material” found on a hydraulics unit – again no issue, and “Auxiliary Power Unit (APU) Magnetic Pickup Unit (MPU) Electrical Connector Rotation,” which also has been closed as an item if IFA interest.

Further articles on the post flight IFA review will follow over the coming week.

L2 members: All 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. SRB Holddown posts undergoing redesign evaluation ahead of STS-119 Engineers will meet in the middle of January to push...
2. RSS retracted to reveal Endeavour – ODS issue cleared for flight STS-126′s S0007 launch countdown operations have reached another milestone, with...
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Endeavour and the SCA were originally due to leave California last weekend, before issues installing the tail cone delayed the trip by a day, with unacceptable weather conditions enroute delaying departure yet further.

Originally, the duo were to take in three States during the cross country ferry trip, before the plan was aligned to best facilitate their arrival back at the Shuttle Landing Facility (SLF). Over 20 military bases are available for selection for stopovers.

The path the SCA and Endeavour have taken so far invovled a trip to Fort Bliss’ Biggs Airfield, Texas, before heading for an overnight stay at Fort Worth, Texas.  The second leg will take in Barksdale, Louisiana, before which there was a flyover of JSC around noon local time.

This was the first time such a flyover has been carried out since Challenger’s SCA ferry flight in 1983, and will be part of NASA’s 50th Anniversary celebrations. 

Processing since the tail cone incident had been issue free, with soft mate operations completed at 05:16 EST on Tuesday, followed by hard mate on top of the SCA.

“Installed tail cone over weekend; had some issues with some attached things, but got by that,” noted the Shuttle Stand-up/Integration report. “Got hydraulics left gear up. Did final power down. Are evaluating weather along route back to KSC.”

The Wednesday morning processing report from the Dryden also noted that the travel plans for the duo remain fluid. It has since been confirmed the duo will arrive back in Florida on Friday.

“Dryden Turnaround Operations: Orbiter hard mate to the SCA, and sling disconnect were completed yesterday. SCA ferry flight departure is scheduled for 1000 EST today, with an expected arrival at KSC Thursday or Friday depending on weather.”

Several items of interest will be fully checked over, once she arrives back into her Orbiter Processing Facility (OPF-2), notably evaluations on her left OMS Pod, which came into contact with a platform/crane during early post flight processing.

“While backing up the orbiter for tow to the MDD (Mate/DeMate) the mobile condor flip-down made contact with the top of the LH OMS Pod. Inspections performed: Minor damage to blanket outer fabric,” noted the STS-126 Ferry Flight Readiness Review (FRR) presentation, available on L2.

“C-9 coating applied to prevent further blanket damage during ferry. No evidence of structural damage. No concern for ferry flight.”

Endeavour also experienced an unexpected vehicle shutdown during her stay in California, which occurred during the transition from orbiter to ground power.

“During transition from vehicle to ground power, all power was lost to the orbiter vehicle. Ambient temperature at the time of powerdown was below 45 degrees F,” noted the Ferry FRR presentation.

“Two concerns addressed for RCS thruster temperature exposure and fuel cell heater operation without coolant flow. RCS thruster temperature exposure. Concern for RCS thruster leakage for sustained temperatures below 45 deg if heaters are not active.

“Ambient temperatures increased above 45 degrees F approximately 3 hours after powerdown. Heated purge air through Orbiter purge circuits remained on. No thruster leakage detected. Unlikely that thruster temperatures fell below the threshold of concern with the short time exposure and positive purge flow.”

Although engineers won’t know for sure if damage to vehicle systems was sustained during the powerdown, until she returns to KSC, a mitigation plan – relating to Fuel Cell 2 – was set up for her cross country ferry trip.

“Due to the sequence of events when main B bus lost power, fuel cell #2 was active while the coolant pump was off. This may have resulted in sustaining heater operation with a stagnant coolant loop and may have caused overtemp and partial decomposition of the FC-40 coolant,” added the presentation.

“Fuel cell #2 will be prepped for ferry flight as follows: 1) Fuel cell 2 will remain depressurized after PRSD detank. 2) No coolant sampling or deservicing at DFRF Coolant system will be evaluated when orbiter returns to KSC.

“3) Depressurize the water tanks to remove potential of water leakage back into fuel cell. 4) Water drain (freeze protection) procedure performed to re-pressurize the
water tanks and to gravity drain water from FCP 2 prior to ferry flight. 5) Installed fuel cell reactant jumper assembly to maintain stable internal pressure during ferry flight.”

Due to the impressive performance of Endeavour Thermal Protection System (TPS) during he mission, and her External Tank (ET-129) during STS-126′s ascent, very few items of TPS interest came back down to Earth with the orbiter.

Those that did, mainly relating to gap filler protrusions, did not suffer from any additional damage. On the mostpart, they simply folded back during the hi velocity and loading of re-entry. Engineers removed any gapfillers that were loose ahead of departure from Edwards Air Force Base.

“Port OMS pod gap filler protrusions: Gap fillers protrusion heights post-landing similar to on-orbit imagery. OMS pod gap fillers folded over due to airflow on entry. Suspect gap fillers removed as required for ferry flight,” noted one example on the Ferry FRR presentation.

“TPS Anomalies: Rationale: All tile damages and gap filler protrusions have been dispositioned as acceptable for the Orbiter’s trip back to Florida.”

Also, during Endeavour’s tow from the Edwards runway last weekend, the left hand outboard tire incurred a small puncture. The depth is uncertain, and the tire was not deflated, but engineers decided it would be the best option to change all four tires with roll around tires (RATs).

She will be rolled from the SLF to her OPF on these replacement tires, where deservicing operations will continue, ahead of preparations for her next flight – STS-127.

This article will be updated during Endeavour’s Ferry trip back to Florida.

Related posts:

1. Endeavour rollaround moved forward to Thursday – FRR concludes The unique transfer of Endeavour and the STS-126 stack from...
2. Dual flow ballet for Endeavour and Atlantis – De-stack debate Preliminary milestone schedules have been created for the complex dual...
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Endeavour’s processing at the Dryden Flight Research Center (DFRC) has been proceeding more or less to plan, with the retraction of work stands from around the Space Shuttle Main Engines (SSMEs) and her Orbital Maneuvering System (OMS) engine nozzles taking place ahead of installation of the aerodynamic tailcone.

“Hyper offload was completed yesterday,” noted Friday processing information on L2. “Aft access installed and Pyro safing complete less resistance checks on drag chutes and drag chute door installation.

“Fuel cell purge and H2O drain/mid-body closeouts In-Work. MPS (Main Propulsion System)/SSME ferry kit leak checks complete less installation of engine locks. Preps for ferry flight continue.

“Hydraulic ops scheduled for today to position engines and aero surfaces for tail cone installation. Working towards being ready for Ferry Flight early Sunday. From an overall schedule perspective, we will be ready to ferry late Saturday, with vehicle leaving EDW on Sunday.”

Operations for the orbiter to be lifted via the Mate-Demate Device gantry, and mounted on the SCA, were to continue through Saturday. However, NASA Public Affairs noted problems with the installation of the tailcone, which has delayed depature by around a day.

On Sunday, NASA noted poor weather had delayed depature to at least Tuesday, before a Monday review delayed the trip once again, this time to Wednesday. 

A Ferry Flight Readiness Review (FRR) took place over the weekend (FRR presentations on L2).:

The SCA and Endeavour are scheduled to take in three US Air Force bases during the trip back to Florida, with that plan likely to be realigned, based on weather conditions at the multiple stopover sites available.

The Sunday departure flight plan previously listed will now be realigned, based on the duo now set to depart no earlier than Wednesday - due to the tailcone installation issue (one day hit) and poor weather (two day hit) along the flight path.

RATs – Endeavour’s replacement tires due to puncture:

During Endeavour’s tow from the Edwards runway last weekend, the left hand outboard tire incurred a small puncture. The depth is uncertain, and the tire was not deflated, but engineers decided it would be the best option to change all four tires with roll around tires (RATs).

These spare tires are staged at Dryden for just such a requirement. The RATs are an old tire design, which have a slightly smaller diameter – which is why all four tires needed to be changed out.

RATs are made up of a set of never flown first generation tires left over after the move to the new tire design. The tires were changed out with the wheel assembly, as orbiter tires aren’t taken off the vehicle by disassembling the rim.

The process of changing out the four Main Landing Gear (MLG) tires at Dryden has been completed.

Priority engineering upon her return to KSC:

Once Endeavour returns to KSC, she will be demated at the SLF’s Mate/Demate Facility, before being towed back, on the RATs, into Orbiter Processing Facility 2 (OPF-2), for continued post flight processing.

One of the top priorities for engineers will be to start the troubleshooting plan on a Flow Control Valve, which is likely in need of replacement ahead of her next flight – STS-127.

“Flow Control Valve Troubleshooting Plan: procedures for investigating and x-raying valve look good. A plan is in place if needed to remove valve for failure analysis,” noted information on the latest Shuttle Stand-up/Integration report.

“At this point, fault tree points toward mechanical failure rather than electrical. The team is ready to take action as soon as vehicle is back at KSC.”

The STS-127 pre-flight processing flow will be aided by the lack of Thermal Protection System (TPS) damage, thanks to the clean flight of the vehicle during STS-126. Other work will center around troubleshooting on the orbiter’s Ku band system, which proved to be problematic on orbit.

Click HERE to watch MaxQ’s amazing STS-126 Review Video.

Related posts:

1. Endeavour rollaround moved forward to Thursday – FRR concludes The unique transfer of Endeavour and the STS-126 stack from...
2. Endeavour and her SCA piggyback ride arrive in Louisiana, via JSC flyover The Shuttle Carrier Aircraft (SCA) and Endeavour departed from Edwards...