ET in focus – ET-119 sent back to MAF

by Chris Bergin

Engineers are focusing their attentions on evaluating if the foam liberation on STS-114’s launch was a one-off situation – caused by previous work under-taken on the PAL Ramp section of the External Tank (ET).

Following a Data Review meeting on Monday at the Michoud Assembly Facility (MAF), where the ET’s are constructed, ET-119 – which was set to launch with Atlantis on her second mission since Return to Flight began, on STS-115 – has been sent back to MAF to help with those evaluations.

Atlantis, currently stacked with ET-120 in the Vehicle Assembly Building at the Kennedy Space Center, with processing continuing despite the date for her launch now in limbo.

Atlantis was set to launch in September with a short window that started on the 22nd of that month.

Even without the evaluations on the External Tanks, Discovery’s landing on the ‘wrong’ side on the US has likely ended any chance of Atlantis launching in September. November is the next available window.

Atlantis will still roll to the pad later this month for an APU hot fire test, before being rolled back to the VAB.

ET-118 – set for Discovery’s back-up mission for Atlantis’ STS-121, classed as STS-301 – is also set to be sent back to MAF for a “repair”. 

The focus on the ETs centres on the liberation of a section of the PAL Ramp.

Since news broke exclusively on this site that the area had been previously worked on – followed by the rest of the media a week later – documents are being checked back on exactly what process was undertaken, including whether that process lead to that section falling away shortly after Solid Rocket Booster separation.

Read the exclusive here:

That ‘repair/patch’ has already been noted as the most likely reason for the problem, with NASA administrator Mike Griffin hinting the solution will be a short process – pointing to a reason rather than a re-design of the ET – one of which could be a metal mesh being installed around the PAL Ramp insulating foam.

“I think we are going to fix it in short order, and we are going to get back flying,” said Griffin. “We don’t expect this to be a long, drawn-out affair, to be honest with you.”

The Data Review’s Tiger Team is still evaluating if that was the specific cause of the shedding – the one reason NASA has currently suspending full launch processing for the fleet.

Finding a solution is top of NASA’s list of priorities to continue the next leg of the “relay” – handing the “baton” to Atlantis on STS-121.

Detailed Data Review revealed only about 25 points of ‘dings’ in Discovery’s Thermal Protection System (TPS) surfaces, nearly one-sixth as many as the previous average of 145 per flight. Further inspections could add to that number, but NASA’s boss was overjoyed with the success of the new Flagship for the fleet.

“In the world of engineering, she did pretty well,” he added.


June Malone, a spokeswoman for Marshall Space Flight Center, has confirmed a repair was carried out at MAF in the exact area of where PAL Ramp foam liberated just after SRB sep during assent on STS-114.

Evaluations are going via the Tiger Team to confirm said repair areas are either inherently a problem for potential shedding, or that the repair was imperfect.

For images and the latest updates, click here:

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