EVA being evaluated for OMS Pod blanket tear as a precaution

by Chris Bergin

Flight Day 4 – altered due to the illness of spacewalker Hans Schlegel – will involve further evaluations on Atlantis’ ripped blanket, which is protruding from the starboard OMS (Orbital Maneuvering System) Pod.

An EVA may be carried out to pin down the piece of TPS (Thermal Protection System) blanket, as a precaution to avoiding extended processing on the orbiter back on Earth.

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

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

**STS-122 Special: 29 Flight Readiness Review (FRR) Presentations, Baselines and Mission Overviews. **Click here for FRR overview articles: Article 1Article 2** Payload Presentations and vast amounts of live, uploaded images and presentations, movies (several) – already 3400 megabytes strong**

**COMPLETE Section – over 1350mbs of presentations – on ECO/Feedthrough Connector issues and troubleshooting, graphical and data based – expansive.**

**LIVE updates on Atlantis STS-122 FLIGHT DAY SPECIFIC**

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

STS-122: Hose related news content (all exclusives): *Issue found/fleet to be checked (December)* – *Atlantis found to have problem* – *Managers discuss forward plan* – *Use of pole to aid retract* – *Successful Retraction*

STS-122 TPS Latest:

STS-122, which was extended by a day during Flight Day 3, is proceeding without any issues of concern with the orbiter. The only real issue is with one of her passengers, who is confirmed to be ill, resulting in the 24 hour delay to EVA-1, allowing for Schlegels’ spacewalk tasks to be carried out by Stanley Love.

Visually, the ripped OMS Pod blanket brings back memories of Atlantis’ STS-117 event, where a protruding piece of blanket has to be ‘prodded’ back down by spacewalker Danny Olivas, during that mission’s EVA-3. A similar task may be required during STS-122.

Interestingly, the location of the rip is different to that observed during STS-117, where the blanket had become ‘unstitched’ from the TPS (Thermal Protection System) tile on the forward section of the pod.

STS-122’s tear is further back on the opposite pod and may hold less risk of peeling back during re-entry.

It may also have all manner of different thermal and dynamic characteristics than those evaluated for STS-117, ensuring the decision to either repair or leave as-is may take at least another 24 hours.

‘Blanket on Starboard OMS Pod observed to have been lifted at one corner (Thermal Blanket Installation Date – 4/29/85, 1.06 inch nominal thickness,’ noted information in an expansive overview presentation.

‘Filler bar perimeter, no stitching to adjacent blankets. Installation paperwork being reviewed to determine if sub-insulation (ramping) is present. Gr/Ep honeycomb structure beneath – defining details (further imagery will be obtained and evaluated, obtain images on an opportunity basis (video and Focused Inspection)).’

Back-up data is aplenty, with OMS Pod blankets coming away from the structure something that is not an uncommon event. This is seen in flight history notes, ranging from STS-117’s event, to some rather scary images from earlier flights in the shuttle program. Each time the orbiter returned home safely.

‘STS-74 (Atlantis’ 15th Flight): Blanket damaged along a previous patch repair. No Structural damage noted. Port side OMS Pod,’ noted the examples, some of which are listed below.

‘STS-50 (Maiden Voyage of OV-105’s OMS Pods): Left Hand OMS FIB damages was initiated by Debris damaging the tile. Right Hand OMS FIB lifted along the tile interface. No Structural damage to substrate.

‘STS 6 (Challenger’s Maiden Voyage): Analysis concluded the AFRSI blanket loss was do mechanical forces by either foreign object impact or aerodynamic forces.

‘There was no significant thermal exposure (>1200F), majority of insulation lost after entry heating. Structural integrity of the undamaged blankets was not degraded. Resulted in the development of C-9 ceramic coating.’

‘STS-95 (Discovery Flight 25): Carrier panel on Y-web door lifted and cracked. Reported on orbit by crew. Overtemp caused delamination of the outer layers of the Y-web door.

‘The exposed section of the carrier panel eroded away around 6 inches of the panel. Removal of the door found no charring or delamination to the IML surface of the composite structure or overtemp to the internal cavity.’

The point that is obvious from the presentations relates to the observation of much more serious damage being seen on previous flights, with the worst cases resulting in repairs back inside the Orbiter Processing Facility (OPF).

Any repair on orbit via an EVA would likely be called to mitigate such additional processing work, ahead of Atlantis’ STS-125 this summer.

Meanwhile, other areas of interest on the orbiter have also listed,

‘Gap filler is protruding around a maximum of 0.44” over a length of 6” – Installation history is being pulled,’ which relates to an area of interest on the same starboard OMS Pod on Atlantis.

Whereas on the opposite pod, ‘Blanket OML is protruding maximum 0.48” over a length of 11” Blanket installed in 1984 – Not bonded to adjacent tile prior to flight. RPM imagery will be utilized assess interface,’ was also observed.

Flight Day 3’s RPM imagery was also used to check on a small area of damage on Atlantis FRCS (Forward Reaction Control System) – helping confirm there are no concerns over what is mainly cosmetic damage to the TPS.

‘Tile damage is adjacent to thruster thermal barrier. Tile seals to thermal barrier for approximately 1.8”. Damage appears to be shallow relative to tile thickness,’ added the presentation.

‘Thermal barrier seal is verified each flow to preclude flow path to structure. Majority of design seal remains to ensure no flow past interface.’

Launch imagery also continues to be checked over, though the highlight appears to be at SSME (Space Shuttle Main Engine) ignition, where a whole tile liberated from the aft end of the left stringer pod.

Pad inspections – which have been carried out and found the structures to be in ‘better’ condition than normally observed – have not found any remains of the tile, which was likely incinerated.

However, this issue is not causing any concern, due to the lack of critical systems in the immediate vicinity. The location is near two vernier RCS (Reaction Control System) thrusters, but they are not close enough to where the tile liberated from to be an issue.

Ironically, despite the tear in the OMS Pod blanket, this appears to be one of the cleanest flights ever, pending full evaluations on the RPM imagery taken on Flight Day 3. Updates will follow after those evaluations have concluded.


Good news for Atlantis’ younger sister, following a couple of days of meetings that concluded with the green light to allow Endeavour to rollover to the Vehicle Assembly Building (VAB) after all. This is scheduled for Monday.

Last week, a HEPA filter contamination problem led to a decision that Endeavour would not be able to support STS-122 as the LON (Launch On Need) orbiter, leading to a debate about Discovery’s ability to be processed in time for stacking with ET-126 and the attached twin Solid Rocket Boosters, in order to take over the role.

Following several meetings, engineers concluded that contamination had not breached critical systems on Endeavour – which was the major concern – allowing her to continue with the flow towards stacking for both LON and her primary STS-123 mission, currently scheduled to launch next month.

Click here for MaxQ’s Stunning Apollo I/Challenger/Columbia Tribute Video ‘New Days Will Rise’.

**STARLIGHT: NEW STS-117 MISSION REVIEW MUSIC VIDEO** – STS-118 and STS-120 Mission review video also available. 

(Video section is FREE, but you need to sign up as a member of the forum to enter the video section of the site. We only use your e-mail to send you your password. It will not be used for spam etc.)

Related Articles