Originally posted by donwhite
On the “more tiles gone.” I too have heard that stated occasionally in the past. Perhaps I have missed the explanations, but is it possible the
missing tiles came off after the re-entry was completed? Or, were the missing tiles in the least dangerous areas?
Yes on both counts. Shuttle is most apt to lose a tile at lower speeds and in the atmosphere. At high speeds the tiles are actually forced against the
belly in compression. But get a hole throught the thermal displacement material into the structure beneath and...
Originally posted by donwhite
Memory fades and I forget whether anyone knew about the missing wing root tiles on Columbia before its attempted re-entry. I don’t think anyone knew
about those which is why we have so many cameras in play today.
Did anyone know? Officially they say not. It actually wasn't a tile issue on STS-107 but rather the leading edge of the wing which wasn't much more
than fancy carbon fiber was struck by a big - no giant piece of BX Foam and likely ice. There's video around. I can't watch it. It's all in the
You don't think the Commander looked out the windows at the wing leading edges or used the original Canadarm camera to look at anything? Perhaps not,
but I would. Boat, airplane and race car/bike folks are "funny" that way.
It is somewhat likely that the STS-107 occupants felt the hit on the way up... maybe didn't "hear" it but felt something. It was a big piece
hitting with big league kinetics. It's all in the CAIB report. The wing leading edge is far more critical than the belly area concerned with STS-118
if that's any consolation. The leading edges of STS wings are now state of the art RCC and studded with "hit" sensors.
Originally posted by donwhite
Challenger was lost due to every prior mission succeeding despite some chances that were taken. All of us grew complacent. Taking a shuttle to low
space was much like catching a Greyhound to Miami. From Canaveral. Routine. I’m thinking we ought to change the ground control people every 2 or 3
years. Just to keep us on the good side of the learning curve and hopefully, alert.
Yup, 117 out of 119 so far, luck is "good", bad management and lack of imagination are not. Complacent? How about demanding? Demanding of perfection
every time and while your at it do it faster and with less staff and less money... oh and by the way your being laid-off in 2010 for four years... and
the public doesn't "care" about NASA. Not complacent - "we" just looked the other way... practically ignored NASA post Apollo 11, make that 13.
Got some people dead twice with this STS platform. It must be difficult. Change ground control? Managers maybe, "grunts" no... aren't any left to
Hey remember when Shuttle was going to be "shirt sleeves to orbit"? I do.
Don't get overwhelmed don, there's only so much one individual can do really other than watch and perhaps wish "good luck" to any venture where
humans altruistically offer themselves into exploration that adds to our species chances. Think about them - they're people, right now 10 people, 2
Russkies, a Canuck and seven Americans. 215 miles up, going 17,500 MPH, space junk, computer and orbiter problems. I envy them.
The voice transmissions from orbit tonight have been absent and the crew should have gone to sleep about 10:30PM EDT. Normally there's some stuff
from ISS and some chatter on the big loop with ISS... solid two hours of nothing.
Originally posted by Badge01
I trust they will take the safer course and keep the Endeavor docked and send up a rescue shuttle should there be any question.
That's actually doable, almost, technically sort of. It involves a bunch of stuff and caveats and risks and both known and unknown unknowns, like
losing an orbiter and possibly evac of ISS and maybe it's loss too, maybe risking the rescue orbiter too, lotsa stuff.
There could be a different scenario, maybe. Bringing in an orbiter unmanned? The Russian Buran did it in 1988 I think (it was missing many, many, many
tiles - only seen the footage once). But I don't know enough about avionics to say whether shuttle can go "data-silent" during the plasma-ball time
of re-entry and "do all computing and networking" to bring in Endeavour, say to White Sands or Edwards via remote or onboard computer - away from
population in case someting were to "not go well", maybe one of the TLA sites.
An orbiter can be flown by 3 people nominally, 2 in a pinch and one-up left seat if required with ground assistance... between Soyuz and Shuttle
(which would have the same spec ET as 118 - same risk) you could recover the crew, if all went perfectly. Earliest Discovery can be up is October,
second or third week and that's with no glitches or ET modifications. I bet there's folks in Houston right now thinking about these same things and
far, far, far more; all the "other" stuff. It must be difficult. It may be "hardest" to do nothing. A protruding repair could do more damage
should it "get a run" and lift a series of tiles.
I think the combination of first applying emissivity "paint" to seal all the divots and nicks and then filling in the big divot with T-RAD
"pink-goo" and smoothing it off with a trowel, let it set and shrink in, apply a second "scratch coat" smooth it out and when dry "paint the
whole works over" with a layer of emissivity paint. After some thought I find the "plate" repair a little scary with drywall-like screws and a 16
or 20 inch square plate. I'll have the "goo" with the paint garnish, hold the plate.
I still maintain that this damage is not a "show-stopper" but it could be depending on what happens in the decision phase. Ultimately Commander
Kelly has last say. I like that.
Can an "ice-free" external tank be built? Yes. It will weigh almost double if a dual wall thermos design is used, more if heaters are required for
localized ice points... which was one of the original Shuttle proposals for the ET design - lost out because of cost, go figure. Whole bunch of
problems follow with the extra mass, not enough motor, etc., etc. Had America to do a Shuttle-like system again it could be very, very good if done
from a clean-sheet. That's not going to happen.
Can the existing three external tanks in the flow be trusted? Good question. Maybe with a "fix" from Michoud or maybe on days that don't promote
icing like in high humidity and maybe that when a crack on a feedline bracket is seen that such an occurence is a "show stopper". Hard to say,
that's NASA's job. The entire planet takes NASA for granted in some ways, me included. Imagine how.
[edit on 13-8-2007 by V Kaminski]