[Space] NASA STS-114 (ISS)

[Athlon]

ma dal discovery gli astronauti possono uscire per un eventuale ispezione manuale dello scafo???

[icestorm82]

Originariamente inviato da Athlon

ma dal discovery gli astronauti possono uscire per un eventuale ispezione manuale dello scafo???

E' una cosa non pianificata, cmq credo di si. L'importante è sapere che il problema c'è ed è reale. Non come sul Columbia che nessuno sapeva. Speriamo bene. Ah, permettetemi un commento. Nessuna televisione nazionale ha trasmesso il lancio ( ); probabilmente ritenevano che gli stupidi telefilm che passano a quell'ora fanno più odience di un lancio dello shuttle così importante. Mah . Personalmente l'ho visto su Fox Tv, riprese eccezionali, tranne per il fatto che, a causa del mio inglese un po' arrugginito non capivo alcuni concetti tecnici su cui si discuteva. Cmq per chi volesse seguire lo svolgimento della missione vada qui

http://www.nasa.gov/multimedia/nasatv/index.html

[drakend]

S'è ancora danneggiato lo shuttle? Dopo tutto il tempo e i soldi che hanno speso per migliorare la sicurezza? Che si sparassero...

[thotgor]

progettare qualcosa di nuovo no??

[icestorm82]

Originariamente inviato da drakend

S'è ancora danneggiato lo shuttle? Dopo tutto il tempo e i soldi che hanno speso per migliorare la sicurezza? Che si sparassero...

Nessuna macchina è perfetta, nemmeno la più costosa e collaudata del mondo. E cmq a bordo dello shuttle ci sono tutti i mezzi per ovviare al problema. E in caso di danno irreparabile gli astronauti potranno stare nella stazione spaziale il tempo necessario per organizzare un viaggio di soccorso.

[icestorm82]

Originariamente inviato da thotgor

progettare qualcosa di nuovo no??

Ci sono già dei progetti per mandare in pensione lo shuttle, ma fino ad ora esso è la macchina più efficiente. Credi che la nasa abbia bisogno dei nostri consigli??

[drakend]

Originariamente inviato da icestorm82

Nessuna macchina è perfetta, nemmeno la più costosa e collaudata del mondo. E cmq a bordo dello shuttle ci sono tutti i mezzi per ovviare al problema. E in caso di danno irreparabile gli astronauti potranno stare nella stazione spaziale il tempo necessario per organizzare un viaggio di soccorso.

Sì ho capito, ma si è verificato un incidente del tutto simile a quello di tre anni fa, mi pare di aver letto. Ora dopo tre anni di attesa e qualcosa come 2 miliardi di dollari spesi per rendere più sicuro lo shuttle che si verifichino ancora incidenti così stupidi come il distacco di oggetti dalla rampa di lancio è a dir poco scandaloso. Quelli non sono soldi loro sai, ma dei contribuenti americani: quindi le solite frasi fatte come "Nessuna macchina è perfetta" lasciano il tempo che trovano.

[thotgor]

Originariamente inviato da icestorm82

Ci sono già dei progetti per mandare in pensione lo shuttle, ma fino ad ora esso è la macchina più efficiente. Credi che la nasa abbia bisogno dei nostri consigli??

si, scusa, mi sono espresso male...

dico che sarebbe veramente ora che si lasciassero un attimino da parte i problemi di budget e si costruissero le cose progettate, piuttosto che giocare ancora sulla vita della gente (che ha anche il coraggio di farsi mandare lassù!)

[GioFX]

Originariamente inviato da Athlon

ma dal discovery gli astronauti possono uscire per un eventuale ispezione manuale dello scafo???

Teoricamente è stata valutata questa possibilità, ma non sarà fatto in questa missione, le procedure devono essere ancora definite anche perchè si tratta di un'operazione estremamente difficile e non sarebbe dedicata solo all'ispezione, ma alla riparazione o con una particolare schiuma di un numero limitato di piastrelle danneggiate.

E' stato costruito un bracico dotato di sensore al laser che viene posizionato sull'estremità del braccio robotizzato dello shuttle (il cosidetto Canadarm, dato che è costruito in Canada, Canada-arm), che permette di scannerizzare tutto la parte inferiore della navetta e il leading edge delle ali.

Tutte le zone più importanti verranno scannerizzate anche dalla ISS una volta che lo Shuttle si sarà agganciato, questa sera.

[GioFX]

Originariamente inviato da drakend

S'è ancora danneggiato lo shuttle? Dopo tutto il tempo e i soldi che hanno speso per migliorare la sicurezza? Che si sparassero...

Ma hai idea di che si tratta?

Le modifiche adottate per ridurre al minimo la possibilità di incidenti fatali causati dalla caduta di matriale isolante o di ghiaccio dall'external tank sono costate circa 2 miliardi di dollari e 30 mesi di lavoro a centinaia di persone...

Se questo ti sembra poco... e poi lo Shuttle è un sistema estremamente complesso, il solo orbiter è il mezzo di trasporto più complesso della storia, ogni eventualità o quasi è presa in considerazione e sono altamente sofisticate le misure di sicurezza per tutto ciò che riguarda la gestione di una missione con lo Shuttle, è per questo che il programma STS costa 6,4 miliardi l'anno, pari cioè al 40% dell'intero budget in un anno dell'agenzia.

[GioFX]

Originariamente inviato da thotgor

progettare qualcosa di nuovo no??

Lo stanno progettando, si tratta del CEV (Crew Exploration Vehicle). Ma non è destinato, come il programma STS, a missioni in orbita bassa ma al ritorno sulla dell'uomo Luna.

Il sistema è di tipo in-line, si tratta di una navetta a capsula simile alla concorrente russa (Kliper), montata in linea su un razzo vettore S-HLLV (Super-Heavy Lift Launch Veichle) che molto probabilmente userà motori derivati dai razzi SRB, Solid Rocket Booster, utilizzati dallo Shuttle (che sono attualmente i più potenti razzi a carburante solido del mondo, mentre quelli a carburante liquido rimane il mega-lanciatore russo Energia, costruito dall'Energia Space System Bureau, ed utilizzato per lanciare in orbita lo shuttle sovietico, il Buran).

[GioFX]

Originariamente inviato da drakend

Sì ho capito, ma si è verificato un incidente del tutto simile a quello di tre anni fa, mi pare di aver letto. Ora dopo tre anni di attesa e qualcosa come 2 miliardi di dollari spesi per rendere più sicuro lo shuttle che si verifichino ancora incidenti così stupidi come il distacco di oggetti dalla rampa di lancio è a dir poco scandaloso. Quelli non sono soldi loro sai, ma dei contribuenti americani: quindi le solite frasi fatte come "Nessuna macchina è perfetta" lasciano il tempo che trovano.

Primo: non è successo nulla di simile al 16 gennaio di due anni fa. In quel caso, in un'evento assai difficile da prevedere e mai verificatosi in precedenza, un pezzo di schiuma isolante si è staccato dal bipod di collegamento frontale dell'ET e ha colpito a velocita super-sonica (lo shuttle aveva già superato la velocità del suono) il leading edge dell'ala sinistra, perforando la struttura di carbonio e facendo si che al ritorno in atmosfera i gas incandescenti entrassero all'interno dell'ala creando un effetto distruttivo per tutta la navetta.

In questo caso, grazie anche alle 114 telecamere fisse e mobili digitali ad altissima risoluzione (prima ne venivano usate massimo 50-60), nonchè alla migliore illuminazione possibile, è stato possibile osservare eventi che cmq accadevano anche prima, in particolare tre: lo scontro tra la punta dell'ET e un uccello pochi secondi dopo il lancio a bassa velocità, il distacco di un pezzo NON ANCORA IDENTIFICATO ma probabilmente un foglio protettivo del rivestimento dell'ET che cmq NON HA COLPITO L'ORBITER e, la cosa più importante, il lieve danneggiamento di almeno due piastrelle del rivestimento termico esterno in carbionio della navetta all'altezza dell'estremità inferiore del vano del carrello anteriore.

Occorre cmq ricordare che il danneggiamento per i più vari motivi è un evento assolutamente comune delle missioni shuttle, basti pensare che in media durante ogni missione diverse decine di piastrelle (che lo ricordo sono una diversa dall'altra) vengono danneggiate in modo più o meno serio, spesso a causa dei frammenti di meteoriti o di "spazzatura spaziale" che colpisce l'orbiter... quindi è un evento del tutto previsto e generalmente non rilevante ai fini della sicurezza della navetta.

Nel caso in oggetto, ancora in fase di investigazione (con una serie di operazioni comunque previste per i primi 3 giorni della missione), è assai probabile che si stato scalfito il rivestimento in vetro delle piastrelle in oggetto.

[GioFX]

Originariamente inviato da thotgor

dico che sarebbe veramente ora che si lasciassero un attimino da parte i problemi di budget e si costruissero le cose progettate, piuttosto che giocare ancora sulla vita della gente (che ha anche il coraggio di farsi mandare lassù!)

Nessuna missione spaziale umana sarà routine prima di molti anni si crede. I voli spaziali sono tutt'ora da considerarsi SPERIMENTALI, pure dopo 50 anni di attività umane nello spazio, e specie con sistemi così complessi e delicati come lo shuttle.

[GioFX]

Sensor boom to scan shuttle during inspections today

BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: July 27, 2005

The Discovery astronauts geared up for a detailed inspection of the shuttle's reinforced carbon carbon nose cap and wing leading edge panels today. The post-Columbia safety survey is designed to spot any entry-critical damage to the areas of the shuttle that experience the most extreme heating during the return to Earth.


An computer-generated illustration shows the wing edge inspections by the new shuttle sensor boom. Credit: NASA

The astronauts also plan to inspect tiles around the upper part of the shuttle's crew cabin and aft orbital maneuvering system rocket pods, along with checking out the spacesuits that will be used later in the mission during three planned spacewalks at the international space station.

Image analysts on the ground, meanwhile, continued assessing the potential significance of at least three debris events spotted during Discovery's launch Tuesday.

The shuttle's external tank suffered a bird hit seconds after liftoff and the apparent loss of a relatively large piece of foam or some other type of debris just after the ship's solid-fuel boosters were jettisoned two minutes and five seconds into flight.

A minute or so earlier, imagery from a new camera mounted on the external tank showed a piece of a black heat shield tile on the edge of a nose landing gear door cracking off and flying away. Mission operations manager John Shannon said Tuesday it would take engineers several days to complete their assessments of the shuttle's condition and that it was premature to speculate about whether any one of the events might, or might not, turn out to be significant.

Lead flight director Paul Hill, speaking well before launch, said he fully expected to see tile damage during Discovery's mission.

"We will likely have coating loss or chips on the bottom of the vehicle that are well within the capability of the (thermal protection system) to bring us to the ground," he said. "It is the nature of having a glass-covered thermal protection system on the bottom of the orbiter. But a we've demonstrated on more than 100 flights, chipped coating on tile, it still performs like a champ. That material will bring us down to the ground, it's very robust. We understand what types of damage change that equation."

With post-Columbia imagery upgrades, Hill said, "we are now going to have all these fabulous pictures of the bottom of the vehicle. We're going to see a lot of white dings, many or all of which I expect we will have in our flight history as cases we have landed with and were absolutely no impact. But we have talked about this a lot, now we're going to be presented with all of this and there is this concern that folks will over react, that we see little things that clearly are within the capability of the vehicle to bring us to the ground but now that we can see it, we may over react.

"There's been a lot of concern about whether or not we'll over react and that would paralyze us for making all of the right decisions during the flight or maybe jumping the gun and repairing a vehicle when we didn't need to repair the vehicle."

But Hill said based on the team's performance during multiple simulations, "we're not going to over react, we are capable of seeing a lot of damage and crossing out the ones that are clearly within our capability and then focusing on the ones that are either right on the edge and we need more data or we're just not happy with it.

"I think we've demonstrated that the community is capable of hearing that story, assessing the data and making good, technical decisions and not making emotion-driven decisions."

Today's inspection activities are unrelated to the debris events seen during launch. Rather, it is the direct result of a recommendation made by the Columbia Accident Investigation Board to "provide a capability to obtain and downlink high-resolution images of the underside of the orbiter wing leading edge and forward section of both wings' thermal protection system."

Columbia was brought down during re-entry two-and-a-half years ago by a hole in the leading edge of its left wing. The Discovery astronauts plan to spend a large part of their second day in space carefully inspecting the leading edges of both their wings, along with the reinforced carbon carbon nose cap of the shuttle, using a new 50-foot-long boom mounted on the starboard side of the payload bay known as the orbiter boom sensor system, or OBSS.

Engineers on the ground, meanwhile, will assess data from new sensors mounted directly behind the leading edge panels that are capable of registering the force of an impact. The wing leading edge sensor data was downlinked overnight.

Astronaut Andrew Thomas will use the shuttle's 50-foot-long robot arm to pick up the equally long OBSS. Starting around 5:30 a.m., Thomas, assisted by pilot James Kelly and Charles Camarda, will maneuver the boom back and forth, using an OBSS television camera and a laser sensor to inspect the wing leading edges and the nose cap.

"Getting the boom, lifting it up out of the payload bay and positioning it to start the survey is all done essentially manually," Thomas told CBS News in a pre-launch interview. "I'll be doing that. Berthing it will be done manually. But once you've got it in the initial position to start the survey, then we invoke computer control sequences which will drive it automatically. And we kind of need to. This thing is 50 feet long, so a small deflection at the end of the arm would be a huge deflection at the end of the boom and you have the risk of hitting structure. So that parts all automated."

Asked what the survey might show, Thomas said "I don't think we'll see too much."

"You know, we have to do this," he said. "They've done all this work on the tank and you have to confirm that what they've done on the tank is as expected. Any debris that's released from the tank is understood and controlled. And the only way you can do that is by these detailed surveys. This flight and the next flight are the ones that are largely going to do that. So we have to do it.

"You point out a risk, though, that there will be sites that will be false alarms, false positives which will exercise the management structure that's on the ground to look at damage sites, compare them to pre flight and make judgments about their importance or otherwise. That's actually not a bad thing to do, though. Because this is the first time it's being done and we need to exercise those procedures.

"I can see, for example, that we will get a call for some targeted inspections of certain sites. ... And I think that's a good thing to do, too, because it exercises the whole organization chain."

Given the launch day debris events, that seems like a safe bet. Here is an updated timeline of today's events (in mission elapsed time and EDT)


07/27/05
Wed 03:09 AM...00...16...30...Centerline camera installation
Wed 03:39 AM...00...17...00...Ergometer setup
Wed 03:54 AM...00...17...15...Orbiter boom survey system (OBSS) unberth
Wed 04:09 AM...00...17...30...Laptop computer setup completed
Wed 04:09 AM...00...17...30...KU-band antenna deploy
Wed 04;39 AM...00...18...00...OMS pod photo survey
Wed 05:19 AM...00...18...40...Rendezvous tools checkout
Wed 05:24 AM...00...18...45...OBSS: Starboard wing LDRI survey begins
Wed 05:49 AM...00...19...10...SAFER jet backpack checkout
Wed 06:19 AM...00...19...40...Lawrence exercises
Wed 06:19 AM...00...19...40...Spacewalk power tool checkout
Wed 06:49 AM...00...20...10...Crew meals begin
Wed 06:49 AM...00...20...10...OBSS: Nosecap survey begins
Wed 07:49 AM...00...21...10...Airlock prep
Wed 08:29 AM...00...21...50...OBSS: Nosecap survey complete
Wed 08:39 AM...00...22...00...EMU (spacesuit) checkout
Wed 08:54 AM...00...22...15...Docking ring extension
Wed 09:24 AM...00...22...45...OBSS: Port wing LDRI survey begins
Wed 10:24 AM...00...23...45...EMU checkout continues
Wed 10:49 AM...01...00...10...OBSS: Port wing survey complete
Wed 10:49 AM...01...00...10...OBSS berthing
Wed 11:44 AM...01...01...05...SRMS survey
Wed 12:59 PM...01...02...20...LDRI downlink
Wed 01:04 PM...01...02...25...NC-3 rendezvous burn
Wed 03:39 PM...01...05...00...STS crew sleep begins
Wed 11:39 PM...01...13...00...STS crew wakeup
Wed 11:39 PM...01...13...00...ISS crew wakeup

A year ago, Hill said in an earlier interview with CBS News, engineers thought entry critical damage to the leading edge panels "required a penetration of the RCC, not just coating damage or even small damage to the substrate on the outside."

"More recent arc jet testing has us worried that coating damage alone, if it's large enough and if we had internal damage - delamination - between the layers, that the combination of those two could be entry critical."

In the early years of the shuttle program, Hill said, tests indicated the leading edge RCC panels could tolerate penetrations a quarter of an inch across. But that testing was with a clean hole punched in the panel, which is what one would expect with a hypervelocity impact in space. But during launch, impact velocities would be much lower and any resulting penetrations would be more ragged.

Engineers then began wondering if lower-velocity impacts might be entry critical. Subjecting RCC panels to re-entry heating in an arc jet furnace, engineers discovered that as long as a protective coating remained intact, internal delamination would not cause any major problems.

"But if the coating is gone and underneath that coating you're delaminated, then picture the RCC itself from a side view like a cross section. Now you've got this bubble or this void in between layers," Hill explained. "What you've done is, you've significantly reduced the density of this RCC that's exposed to the heat load. So it burns faster.

"So now instead of being this more solid material that's hard to light, kind of like if you take a piece of hard wood like oak and you hold a match to that oak, it won't light typically. But if you shave off some splinters of that oak, you can get them to flash. Damned if that's not what we found in a handful of RCC runs for uncoated RCC."

For the tests, engineers deliberately damaged an RCC panel by pushing on it with a metal cylinder. After confirming the panel developed delamination as a result, "they put that bad boy under the arc jet and it burned like there was no tomorrow. The whole area that covered the delamination burned off like a fuse."

If it is credible that the shuttle could take an impact that has enough energy to cause delamination and loss of coating, "then that does not have to be very big to be catastrophic," Hill said. "From an RCC damage perspective, that looks like a penetration. So now the question is, do we believe that testing? Have we done enough of those tests to be sure that is an entry critical damage form? And then, is it credible for us to take an impact that could cause that kind of damage?"

One OBSS laser sensor, known as the laser dynamic range imager, or LDRI, dwill be used to inspect the wing leading edge panels and the shuttle's nose cap. A second sensor, known as the laser camera system, or LCS, may be used later to focus on a suspect area or to collect additional data.

"If you think about the laser, the way we're recording the data is similar to recording video," Hill said. "Imagine standing on the side of a soccer field watching one of your kids play soccer with a camcorder. And you're panning that camera real fast so you can watch him run down the field. But when you play it back at home, you can't make out hide nor hair because everything is blurred. That's the problem we've got. We've got a translation constraint. If we move too fast, we blur the image, which directly affects the resolution and we can't see the small stuff we're looking for."

[GioFX]

1810 GMT (2:10 p.m. EDT)

NASA believes the bird struck by Discovery's fuel tank was a buzzard. These large birds can have a wing span of more than six feet and the average weight of a full-grown bird is 6.5 lbs.

"It was in the wrong place at the wrong time," a Kennedy Space Center spokesperson said.

NASA has long assumed that the noisy launch pad environment at the time of main engine ignition would cause bird to fly away from the launching shuttle.

Workers had not located the carcass of the bird but not all areas of the launch complex had been searched.

Images of the strike are available here.

The incident is one of several NASA is studying from yesterday's launch, along with the chipped nose gear door tile and external tank debris-shedding event.


1851 GMT (2:51 p.m. EDT)

Flight controllers have e-mailed the crew a PowerPoint presentation containing details of the early analysis of imagery captured during Discovery's climb to orbit yesterday. Mission managers are expected to reveal the initial findings to the news media in a press conference scheduled for 5 p.m. EDT today.

[icestorm82]

Originariamente inviato da GioFX

Sensor boom to scan shuttle during inspections today

BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: July 27, 2005
....CUT....

Perciò hanno trovato danni???

[GioFX]

Originariamente inviato da icestorm82

Perciò hanno trovato danni???

NO, ma identificato l'oggetto che è volato via al momento del distacco degli SRB. Si tratta di un prezzo della copertura del condotto PAL:

2055 GMT (4:55 p.m. EDT)

Images and video taken from shuttle Discovery of the discarded external fuel tank following launch yesterday has revealed a section of foam from the Protuberance Air Load (PAL) ramp came off the tank. The debris appeared to just miss striking the orbiter's right wing.

Images of the damaged Protuberance Air Load (PAL) ramp captured by cameras aboard Discovery after the orbiter separated from the tank about eight and half minutes after launch.









2143 GMT (5:43 p.m. EDT)

Debris seen falling away from the shuttle Discovery's external fuel tank during launch Tuesday was a large piece of foam insulation from a so-called "ramp" used to prevent turbulent airflow around cable trays and pressurization lines, NASA officials said today. Other areas of foam loss could be seen in images of the tank shot by Discovery's crew and released by NASA Wednesday.

[GioFX]

External tank lost large chunk of foam

BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: July 27, 2005

Debris seen falling away from the shuttle Discovery's external fuel tank during launch Tuesday was a large piece of foam insulation from a so-called "ramp" used to prevent turbulent airflow around cable trays and pressurization lines, NASA officials said today. Other areas of foam loss could be seen in images of the tank shot by Discovery's crew and released by NASA Wednesday.

The loss of foam debris led to the shuttle Columbia's destruction and while the debris that fell from Discovery's tank did not strike the orbiter, the incident is a potentially serious setback for the shuttle program.

Seconds after Discovery's solid-fuel boosters separated two minutes and five seconds after launch Tuesday, a relatively large piece of debris could be seen peeling away from the tank and quickly tumbling away in the supersonic airflow. Earlier, part of a heat shield tile near the nose landing gear door cracked off and fell away, but that incident appears relatively minor.

The large piece of tank debris passed under the shuttle's right wing and did not appear to come close to actually striking the orbiter. But sources told CBS News earlier today the size of the debris was a shock. NASA's return to flight in the wake of the Columbia disaster has been driven by an accident board recommendation to minimize, if not eliminate, foam debris shedding. The loss of relatively large pieces of foam from Discovery's tank indicates the agency failed to meet its No. 1 post-disaster objective.

NASA hopes to launch the shuttle Atlantis in September, but the timing of that flight and subsequent missions is in doubt pending the outcome of troubleshooting to figure out what caused the foam to fall away from Discovery's tank. And what might be needed to fix the problem. NASA engineers discussed eliminating the so-called PAL ramp in question, but ultimately left it in place.

NASA plans a news conference within the hour.

[GioFX]

2225 GMT (6:25 p.m. EDT)

Mission Management Team chairman Wayne Hale says engineers are treating chipped tile on the nose landing gear door seriously but "not losing sleep" over it. Further observations will be needed to determine the exact size and depth of the divot.

There's also a tile hit a bit lower on the underside. The station crew will be imaging Discovery's belly during approach before docking in the morning.


2230 GMT (6:30 p.m. EDT)

Hale says NASA wanted to remove the PAL ramp foam. But aerodynamically it was determined they were needed to cover the cable trays and pressurization lines running along the tank's exterior. Whether the foam could be replaced with a metal cover is one possibility.


2232 GMT (6:32 p.m. EDT)

Images from the umbilical well on Discovery looking at the jettisoned tank as it moved away shows foam divots in the foam near the struts that connect the orbiter's nose to the tank. These are "areas not satisfactory to us" for foam loss, Hale says.


2233 GMT (6:33 p.m. EDT)

Hale says Discovery appears to be good shape, but the final rationale for returning to Earth as-is or whether any repairs are necessary will be made later this week.

[icestorm82]

Fiuuu, allora possiamo tirare un sospiro di sollievo.