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NASA examining Shuttle's dings, extending mission

PC Paul

Foam > Ceramic?? 

What kind of foam is this anyway, that can smash through thick ceramic tiles?

Could they not spray some sort of plastic coating onto the tiles which will protect them from (what ought to be) fairly trivial impacts but would burn off during reentry, or even during the flight to orbit?

Dr. Ellen

Wrong-side-to 

When they designed this puppy, they should have had the underside away from the fuel tank and its ice and foam!

Chris Roughneen

Great close-up.... 

....exactly how do they get such a clear shot from the ground?

Do they use a super-powerful camera/telescope combo or similar?

Assuming it is shot through the atmosphere the clarity is quite astounding.

Jim Ned

If I were an astronaut 

Imagine yourself sitting on the Space Station. You try to go about your work while parked right outside, your ride home has a hole all the way through its heat shield. On the ground, the 'rocket scientists' at NASA are trying to decide whether to fix it or just 'go for it' as is. IS IT ANY WONDER THE ASTRONAUTS GET DRUNK?

Steven

Re: Great close-up.... 

They take piccy's from the flying killer drones of course....

...or on a cloudy day possibly use the orbiters camera tipped boom to have a butchers are the soft underbelly of the shuttle.

;)

Andy Goodair

I've got this great idea! 

They could cover the foam on the external tank with some sort of covering designed to hold it in place - maybe something like a coat of paint would do the job?!!

What, you mean they used to do just that, but stopped because it freed up a little weight for extra payload. Don't be silly, who'd do anything that stupid!!

James Dennis

Re: Great close-up 

Photos are taken on approach to the ISS.

Chris

About the close up 

The close-up is shot from the International Space Station. If they could shoot such clear shots from the ground, military satellites would just become orbiting mirrors with various ground camera's being periodically updated at a cheaper rate than firing them into space ;-)

..and yes, regarding the foam - I also wish NASA would at least try to publicly explain how foam rips holes in ceramic tile. I don't doubt them, just would be nice to know WHY. I know ceramic is hard but brittle, and perhaps this only happens with usually soft foam coming off at Ludicrous Speed or foam covered in a layer of ice, but it always sounds like some pink bubbly cushions floated off the main fuel tank at lift-off and savagely cut into the shuttle...

Jason Aspinall

@PC Paul 

Mmm, I've always wondered what this foam stuff actually was too... Concrete?

Anonymous Coward

Great closeup 

It isn't shot from the ground.. the shuttle inverts to that the underside is facing the Space Station and the film from there and send the results to NASA....

Chris Morrison

Lots of questions 

The foam is freezing cold making it very hard (like Ice) the tiles are very soft (u could push your finger nail into them)

Where would you put the fuel tank other than on the back?

They don't photo it from the ground they get out a big stick from the back of the shuttle (and soon from the space station) and stick a wee digi camera on the end of it and take lots of photos!

Chris

Robin

hypersonic foam 

re: Foam > Ceramic:

When that foam breaks off it is rapidly decelerated in the slipstream and hits those tiles as some rate of knots (insert SI unit as desired ;) The ceramic tiles themselves are a sort of ceramic foam, something a lot weaker than your dinner service.

"[the tiles] consist of fine glass fibers organized in an open cellular pattern, so that tiny spaces account for 95% of their volume".

http://helios.augustana.edu/astronomy/space-shuttle-tiles.html

Re: Great close up:

That pic was taken from the ISS, that's why they do the backflip before docking.

adam

re: Foam > Ceramic 

To simplify what Robin said above:

Yes. At 5, 10, or 15K mph, impacts from foam will cause damage to just about any surface, even if it's just a glancing blow like the impact that caused the hole in the picture.

andrew mulcock

what could have been 

the shuttle was designed to be taken to near space by a lifting body, a sort of super jumbo, not these great big fire works they now have, light and forget.

the posh name was HTHL, horezontal take off , horizontal landing.

http://en.wikipedia.org/wiki/Lifting_body

so the tiles being brittle did not matter so much, as they were protected by the slow take off speed and gentle handeling, and very light was an advantage,

Then cost cuts come in, and hay presto, you make the typical engineering decision, the best of a bad job.

The tiles have never been covered or painted. The external tank was origionaly painted, but bits flaked off even then. The major problem seems to be Ice, formed around the tanks, which has always been a problem using super cool stuff like LOX and H2. look back at the apollo launch films, you will see ice every where.

http://www.youtube.com/watch?v=5Vc4X4hKuAc&mode=related&search=