Author Topic: Shuttle Q&A Part 5  (Read 865081 times)

Offline Fequalsma

  • Full Member
  • ***
  • Posts: 353
  • Liked: 4
  • Likes Given: 0
Re: Shuttle Q&A Part 5
« Reply #3480 on: 10/03/2017 12:39 AM »
Here is a link to an AIAA paper on the Orbiter TPS:
that Wayne Hale also mentioned in his L2 post:

Yes. What they used pre-Challenger was stock 3M ScotchGuard that was sprayed directly onto the orbiter. It was later found that the ScotchGuard wasn’t working too well with the adhesive used to bond the tiles to the orbiter. This caused alot tiles to debond and was what was really behind the “TPS issues” with Challenger that forced her substitution with Discovery for STS-51C. In fact the problems were so severe that they removed Challenger’s original body flap and used the one intended for Atlantis. The body flaps were never changed back prior to the loss of Challenger so even to this day, Atlantis still have the refurbished body flap from Challenger.

Offline AJA

  • Full Member
  • ****
  • Posts: 856
  • Per Aspera Ad Ares, Per Aspera Ad Astra
  • India
  • Liked: 135
  • Likes Given: 203
Re: Shuttle Q&A Part 5
« Reply #3481 on: 11/14/2017 08:00 PM »
First post back in a long time... and that too when I realised that I already knew a place where someone would have an answer for the question I'd ask.

I was catching up on Wayne Hale's posts - and then scrolled down to see the post on the PAL Ramps.

Then it struck me.

Was the possibility of spraying the protective foam on the underside of the orbiter ever mooted? It could have been manually/automatically discarded once the shuttle achieved orbit (chucked into a decay orbit), or even once it was out of a bulk of the atmosphere (perhaps at altitudes where expendables shed the payload fairing) - on the way uphill, after ET Sep.

That'd have made the stack a little more immune to foam IMPACTS on the TPS?

(It might have exacerbated some other problem - like impacts to the SSME nozzles/boosters, or may have made the aerodynamics very very untenable?)

Can someone point me in the way of the material that did the analysis of this mitigation possibility?

Online DaveS

  • Shuttle program observer
  • Senior Member
  • *****
  • Posts: 7770
  • Sweden
  • Liked: 300
  • Likes Given: 12
Re: Shuttle Q&A Part 5
« Reply #3482 on: 11/19/2017 10:12 PM »
Any Shuttle Entry FDOs left around here? If so, what was generally the de-orbit burn targets like? I'm thinking of Hp and de-orbit burn to EI angles.
"For Sardines, space is no problem!"
-1996 Astronaut class slogan

"We're rolling in the wrong direction but for the right reasons"
-USA engineer about the rollback of Discovery prior to the STS-114 Return To Flight mission