NASA: Shuttle Temperature Rose Suddenly

Yahoo News ^ | 2/2/03 | Paul Recer - AP

[chaosagent]

Yeah, I remember hearing Bob Crippen talking about this in the early days saying RTLS gave him nightmares. Said that neither he nor any other pilots could consistently land safely after RTLS in the sim.

Too many variables in the flight dynamics.

[The Iguana]

That's why 'casual observers' are just that. They don't know all the facts.

Maybe so.

If so it points to a larger flaw in the design.

But then I think we all knew this was a flawed design to begin with - a slapdash compromise, as Feynman pointed out.

[Jhensy]

Yeah, thanks for giving me that link...hard to believe, but I haven't been watching that much coverage of the tragedy, and I just happened to catch that 'sideways' video for the first time an hour ago. It struck me as intruiging, as many others found it, but reading the thread convinced me it's just lens distortion. Carry on.

[Arthalion]

You are incorrect. I'm an avid reader, and a spaceflight fanatic, and I remember reading several years ago that some NASA engineers in the early days of the shuttle program had worked out an "alternate landing mode" and proposed it to the higher-ups.

The plan, if I remember correctly, basically involved using a much shallower rate of descent. The shuttles would have spent an extended period of time at the atmospheric interface (where atmospheric density is at its lowest) bleeding off most of its velocity before dropping into the atmosphere. The result for the shuttle was far less stress on re-entry, and a much lower amount of heating on the tiles. The administrators at NASA ended up rejecting the procedure, however, because it would have increased the length of the landing sequence fivefold (IIRC). The proposition was that this procedure be adopted as the standard landing sequence, and from that perspective I can understand why it was rejected, but there is NO reason something like this couldn't have been attempted in an emergency where tile damage was a possibility. Even reducing the outside temperature by a few hundred degrees might have made the difference and saved those men and women. Of course, maybe it wouldn't have...but at least THEN they could have claimed to have tried everything.

I've spent a bit of time today digging and calling around trying to find the original source of that article, but I do recall that it was written by one of the original shuttle designers in 1979. What it reveals, though, is that there WERE things that could have been done if NASA had been aware of tile damage. This "we didn't check because we couldn't have done anything" nonsense is counterintuitive and goes against every engineering rule NASA has ever espoused. The result of all of this, I'm sure we'll discover later, is that someone didn't want to be bothered, and seven people lost their lives because of it.

[Blood of Tyrants]

In other words, if too many tiles or the wrong tiles come off on the way up, you are screwed? Somehow, that doesn't reassure me that the space shuttles are all that safe.

[_Jim]

Because of the concern about the incident at the launch involving the material that fell off of the structure between the shuttle and the main booster, had there been a great deal of damage I think the camera's around the launch pad would have picked up extensive damage on the surface beneath the wings. You would have to lose alot of tiles to increase the drag that is being talked about during the press conference.

Comment: Damage, although not evident, could still be present. Damage could also have been inflicted to the doors covering the wheeel wells. This looks to be a more likely scenario given the sequence of temp sensors losses and/or elevated temps followed by their loss too.

Do you understand that *some* of what they were indicating was the *loss* of the wiring to various temp sensors?

This last point is VERY important. It means something was buring through or something was being ripped away. Ripped away!

To instigate the amount of force needed to counter rotate the shuttle to the degree that had to occur to bring the inertial controls significantly online as they were

Comment: Attitude control. And they are online during this portion of flight continuously.

The attitude controls were correcting for an apparent roll to the left. As time went on - more correction, more Elevon deflection, was required.

reporting today would take more then a few tiles falling off. So if I am right that the tiles are a red herring, I

Comment: At mach 18 - I don't know the numbers ... depending on where the tiles were lost - or perhaps it was a corner of the wheel-well doors ...

have to envision a situation where there is a gradual loss of control. If the shuttle slowly began dipping the left

Comment: At no point (yet) did they lose control - more 'trim' was being required as TIME went on - indicating, perhaps that tiles were being stripped off slowly ...

wing toward the earth with the inertial control system trying to counter it, I envision a slow see-sawing of the

Comment: Attitude control. More and more input to the Elevons to 'correct' for a tendency of the shuttle to 'roll' left - due to drag on the left side.

left wing dipping down and then partially, but not completely, correcting the attitude, with the resulting heat measurements over the left wing surface and upper left

Comment: Here's where you're wrong. The corrections from the Elevons appear to work here (later - who knows).

Also - you can't account for the gradual loss of the temp sensors during this time.

The only thing that makes sense is - there was a hole on the wing - leading edge, underneath at the wheel well or top - somewhere.

side of the fuselage rising as it is exposed more and more to the atmosphere. I don't know where the telemetry

Comment: Nope. Roll is indicated to be corrected for (so far).

electronics and antenna are located, but it wouldn't

Comment: On top. surprise me if if was housed somewhere near the top of the fuselage and maybe even on the left hand side.

I believe the rise in temperatures after the loss of the telemetry dramatically increased, with the explosion that has been seen in the video all day long being the result.

Comment: This sentence doesn't make sense to me!

We don't have *any* data after the loss of telemetry (data transmitted from the shuttle).

I don't know how the elevon control structure works but a slow degredation of the attitude is consistent with the

Comment: BUT - the attitude was corrected .. but something was dragging - what was it?

Wheel well door? Tiles? Elevon damage? Internal hydraulics?

increasing temperature, before they it became critical, which occurred after the telemetry was lost.

Comment: At some point - the continued inputs for attitude adjustment made by the flight could no longer correct for more 'drag' on the left. At that point - they were in mortal danger!

Burn-up would follow ... as they shuttle was no longer in a nose-up position with it's best heat shields (on the bottom basically) doing their job ...

[hopespringseternal]

The Challenger commission turned up many examples of single point of failure vulnerabilities in the shuttle.

That is largely due to the politics surrounding its design. NASA's first approach probably would have been much more resiliant, but congress deemed it too expensive. As it exists today, the shuttle is not what anyone would wish for, it is what could be built given the political climate.

While it may have been possible to avert this disaster (but probably not), it would have required a certain amount of paranoia that would otherwise be paralyzing.

It is important to remember that shuttles aren't the only things that go down in flames. This sort of thing is just going to happen. In this case, NASA does not appear to have been negligent as they were preceding the Challenger incident.

[_Jim]

This is the first time I have read mentioned of "open source" contribution to space shuttle flight software, i

I'm KIDDING!!

[No Truce With Kings]

"Anyone know how fast the shuttle was going 80 seconds after launch? Some folks are having a problem believing it could have damaged anything, I mean it was foam , right?"

Pretty fast. Supersonic at least. Once upon a time I could have rattled that off without checking the book, but now I have trouble remembering my new telephone number.

MaxQ -- the maximum aerodynamic pressure point for launch occurs at T+73 (Go for Throttle-up) This is seven seconds after that. Probably about 2-3K MPH.

It was foam, but I was told it was a big honkin' piece, bigger than any that had come off before. One thing that worries me, although (unlike *some* others on this thread) I have to concede that I am speaking through my posterior oriface on this one -- could there have been ice on the foam?

If damp had seeped through the foam the cryos in the tank could have frozen the moisture. In March through November the Cape is warm enough that the ambient air would quickly melt any ice, but if the temp had been in the 40s or 50s maybe it would not have been hot enough to melt ice between the foam and the surface of the tank. Then, when the insulation ripped off you would have iced foam hitting the wing -- the difference between getting hit with a snowball and an iceball. Again, though, I have no facts, just a feeling. That and a buck will buy you a coke.

[VRWC For Truth]

Dittemore is in the arena.

Dittemore is out of his league.

[No Truce With Kings]

"But what if you also add the delta-vee available to the ISS? I know there were other obstacles, but what if they started preparing a rescue the day after launch?"

The orbits were in different inclinations. ISS could not have made the plane change.

[_Jim]

There is always a possibility of some type of heretofore unknown sabotage.

Maybe in the movies ... there are just too damn many technicians running around watching, observing, who *know* each other projects like this ...

Quality inspectors known as QA (Quality Assurance) or QRA (Quality Reliability Assurance) personnel check and double check and quite literally 'buy off' (stamp paperwork) for all work performed ...

I would rate this likelyhood as zero.

[chimera]

There have to be solutions to save the crew that do not require repair of the vehicle.

In this particular mission, there isn't much they could have done other than stay in orbit. They don't have in-flight tile repair/replacement capability. The orbital mechanics were such that they couldn't reach the ISS and even if they could they didn't have the docking adaptor or EVA suits to make an open crossing.

So you have to have someone go get them. And in the meantime try to hold out with the consumables you have and hopefully not have to jettison someone out the hatch to keep the others alive. Now, who would go get them? Shuttles take a minimum of weeks to get ready for launch. How many of the Columbia crew would have to be put out through the hatch to keep the others alive waiting for rescue? NASA doesn't like to think about those kind of contingencies. The Russians? I heard they had put Buran into mothballs or maybe were trying to sell it on e-bay? Soyuz? Do they have one ready to fire? Even if they did, well, you have a problem with overcrowding. Assuming one pilot to bring up the Soyuz, would there be room for seven others? If not, who goes and who stays behind to die?

Point is, we just don't have the infrastructure or financial commitment at this stage of our spaceflight development to keep these kinds of contingencies available. Like everything, you have to do the best you can with the resources you have, doing as much with it as possible within limits. That sometimes means taking risks, which, if things go wrong, always leaves you open to Monday morning quarterbacking.

[Blood of Tyrants]

Bummer. So if the wrong tile or too many tiles come off, you are basically dead.

[Othniel]

Or, as in Red Dwarf, build the ship out of those little plastic dolls that seem to survive every major disaster known to man: plane crashes, volcanoes, earthquakes, etc.

[No Truce With Kings]

"Dittemore is out of his league."

Please share your basis for that statement. Be specific. If you cannot justify it, you should withdraw it. At least an adult would.

[NormsRevenge]

Thanks.

This is not a minor event in my mind.

To all those of you picking on the software and sabotage angle or someone was tampering with controls remotely thru telemetry channels, I'm not buying it.

But, as I am all too often prone to say, Time will tell.

[Moonman62]

The orbits were in different inclinations. ISS could not have made the plane change.

I know, but inclination changes can be made with thrust.

[Will_Zurmacht]

I enjoy reading these threads because there are people here at FR who obviously know what they are talking about. I am not one of them. That being said, from my amateurish take on the situation, couldn't this vehicle have been designed better?

Using thousands of extremely fragile tiles to dissipate heat and protect an extremely fragile aluminium body seems very odd to me, but I am surely no scientist. I figure it all has to do with weight and cost, but it strikes me like we built a balsa wood car with pillows for bumpers. Granted, it's a stupid analogy, but riding a rocket is dangerous enough, why increase the risk to save a few bucks?

Prayers for the crew and folks on the ground....

[No Truce With Kings]

"Bummer. So if the wrong tile or too many tiles come off, you are basically dead."

It's not the answer I like, but it's the answer we have to live with.