PB666

Hiting the wing is an inertial force, when it hit the top of the tank, according to the report, it tore open the top of the tank and sent oxygen into the hydrogen, when it hit the orbiter it factored into the disintegration. The time it took between hitting the tank and hitting the orbiter was on the order of milliseconds, read the report. READ the whole report, not just the part you like. dense.

That's because they were separating two things, foam and ice, when Ice gets in the foam it becomes rigid and gains inertia, and so it is susceptible to added stress, and when the foam breaks it has more inertia, its travel is less directed by air, it can travel horizontally farther. The ice was a problem and the foam is a problem and the two combined is a big problem. After the ISS the crew support function was redundant with other functions, and if your payload bay was not full, it was a waste, better to use a supply vehicle. WOuld you get off of this, it had 133 successful flights, some things were done right, again the engineering discussion is about the critical flaws, not "i feel like it was a flaw and therefore it was a flaw".

If the crew had been hit by a separated booster then they all died, anyway and it also means you did not read the report, the SRB hit the orbiter, large inertial forces ensued and aerodynamic stress quickly followed. The crew capsule is not made of fairy dust, it has weight and structural limits.

That is an opine, not a fact.

But with as many ice related incidence the risk created by the ice was obviously the highest, this is about risk, not whether you can make something perfectly safe (per other conversation about sucking it up). But as Tater very aptly points out, the problem begins on flight number 1 and no effective mitigation was employed after 100 flights, that is an administrative problem, not a structural problem. The shuttle was a complex launch system, it may have been too complex for NASA to manage, that in and of itself does not make the general design bad.

https://spaceflight.nasa.gov/outreach/SignificantIncidents/assets/rogers_commission_report.pdf "Just after liftoff at .678 seconds into the flight, photographic data show a strong puff of gray smoke was spurting from the vicinity of the aft field joint on the right Solid Rocket Booster" " Solid Rocket Boosters were increasing their thrust when the first flickering flame appeared on the right Solid Rocket Booster in the area of the aft field joint. This first very small flame was detected on image enhanced film at 58.788 seconds into the flight. It appeared to originate at about 305 degrees around the booster circumference at or near the aft field joint." "One film frame later from the same camera, the flame was visible without image enhancement. It grew into a continuous, well - defined plume at 59.262 seconds. At about the same time (60 seconds), telemetry showed a pressure differential between the chamber pressures in the right and left boosters. The right booster chamber pressure was lower, confirming the growing leak in the area of the field joint." "As the flame plume increased in size, it was deflected rearward by the aerodynamic slipstream and circum ferentially by the protruding structure of the upper ring attaching the booster to the External Tank. These deflections directed the flame plume onto the surface of the External Tank. This sequence of flame spreading is confirmed by analysis of the recovered wreckage. The growing flame also impinged on the strut attaching the Solid Rocket Booster to the External Tank" " Noting that the lower attachment point was being damaged. "The first visual indication that swirling flame from the right Solid Rocket Booster breached the External Tank was at 64.660 seconds when there was an abrupt change in the shape and color of the plume. This indicated that it was mixing with leaking hydrogen from the External Tank. Telemetered changes in the hydrogen tank pressurization confirmed the leak. Within 45 milliseconds of the breach of the External Tank, a bright sustained glow developed on the black - tiled underside of the Challenger between it and the External Tank." "At about 72.20 seconds the lower strut linking the Solid Rocket Booster and the External Tank was severed or pulled away from the weakened hydrogen tank permitting the right Solid Rocket Booster to rotate around the upper attachment strut. " Page 68 "The intertank region of the wreckage contained buckling in the fore and aft direction consistent with this impulsive thrust. Similarly, the right side of the intertank showed signs of crushing. This crushing is consistent with the rotational impact of the frustum of the right Solid Rocket Booster with the External Tank following complete loss of restraint at the aft lower strut attachment area. " The booster is now rotating around the forward support in the direction of the tank. " At about the same time, the rotating right Solid Rocket Booster impacted the intertank structure and the lower part of the liquid oxygen tank. These structures failed at 73.137 seconds as evidenced by the white vapors appearing in the intertank region. " Swithing to the material analysis "There was evidence that during the breakup sequence, the right Solid Rocket Booster struck the outboard end of the Orbiter's right wing and right outboard elevon. Additionally, chemical analysis indicated that the right side of the Orbiter was sprayed by hot propellant gases exhausting from the hole in the inboard circumference of the right Solid Rocket Booster. " Page 67. ". The bottom side of the right wing showed some indentation on the tiles that make up the Thermal Protection System. This indentation was consistent with impact with the right booster as it rotated following loss of restraint of one or more of its lower struts. The frustum of the nose cone of the right Solid Rocket Booster was damaged (photo E) as if it had struck the External Tank, but there were no signs of thermal distress." And back to the photo analysis " he upper photos show, from left to right, the left side of the orbiter (unburned), the right lower and upper rudder speed brake (both burned damaged) and left upper seed brake (unburned), confirmation that the fire was on the right side [the SRB defective side] of the stack" The outgas detected was that of the SRB. IOW before the SRB detached it had already stricken the ET and the orbiter and had partially exploded down direction upon impact. "The right frustrum shows impact damage at top and burns along the base of the cone; evidence indicates it was damaged when it impacted with the External Tank. " " Within milliseconds there was massive, almost explosive, burning of the hydrogen streaming from the failed tank bottom and the liquid oxygen breach in the area of the intertank. At this point in its trajectory, while traveling at a Mach number of 1.92 at an altitude of 46,O00 feet, the Challenger was totally enveloped in the explosive burn. The Challenger's reaction control system ruptured and a hypergolic burn of its propellant s occurred as it exited the oxygen -hydrogen flames. The reddish brown colors of the hypergolic fuel burn are visible on the edge of the main fireball. " "The Orbiter, under severe aerodynamic loads, broke into several large sections which emerged from the fireball. Separate sections that can be identified on film include the main engine/tail section with the engines still burning, one wing of the Orbiter, and the forward fuselage trailing a mass of umbilical lines pulled loose from the payload bay." IOW, in our theoretical model in which such damage can occur randomly, there is nothing stopping the SFRB from striking the orbiter and exploding, in fact in the cold weather model it exactly struck the orbiter and it appear after it struck the ET that it was burning out something somewhere down the fulstrum. At the point it struck the orbiter approximately there is evidence of an reaction control fuel explosion as noted by the orange glow in the cloud, but it does not seemed to have burned the orbiter. IN parting this conversation, a decaying SRB can under a variety of circumstances free itself from some core body and begin rotating or translocating in the direction of the PL vehicle. Thats what the report describes. Rocket had hole, hole got bigger, fried its attachment point twisted around the other fulstrom and struck to bodies in rapid succession amidst large increasingly powerful explosions. Such that if the upper fulstrum, now under much more force breaks it can flying into any part of the orbiter or any other rocket core if that core happens to be along the vector of travel when it breaks. Again the bad here is the SRB. In an ideal world if you can down throttle and you had adequate sensors you then do down throttle both engines and you separate them prematurely and let the range officer take care of them.

It was described, go back and read.

Err the inertial forces initiated when the booster hit the wing and a bunch of liberated RCS blew de f up. Breach meant they had 15 seconds to take action after which no air to breath no escape from hatch no open hatch, the hatch worked nominally. Whatever the case, the SRB caused the accident, not the orbiter or the red tank. The report clearly blames the SRB and blames nothing else. The reports states specifically that the SRB hit the wing and glanced off the core. The absolve the ET in all cause of the force generation as it occurred after RCS ignited. Therefore the source of the inertial was the SRB and the source of the aerodynamic shift again was the SRB and RCS. I repeat again if you had a crew escape, there is nothing to prevent the SRB from hitting that section of the orbiter.

This aspect has been extricated from the necrophobic STS discussion and the like. Makes no sense to go on shooting a dead horse, but obviously some people get alot of pleasure out of it. So let them continue to live in the past, antiquated policies and luditic ambitions. This is a thread for the forward looking. In a past life we had the flexible although somewhat limited STS system which took part in repair of satellites, assembly of ISS and finally its no more, for better and worse. The ISS has a robotic arm and has involved itself in assembly . . . . . but it sterically hindered and its function and inertia limits its use in other occupations. So the question is whether NASA has a viable plan for a space factory or assembly station. I think that before you can build a station of that type you need to decide where its going to be. But we here in KSP are not limited by what any space agency thinks, since the powers-that-be (rattling the moderators cage ) endowed each of us with a brain, its best we put it to our own use and create. And as creators and artist we will tolerate the failings of each other but accept the critiques as a means of communicative growth. But the argument does have to be constrained by what is currently feasible. So for example we could could say build a launch pad in say Boca-Chica for that 50 kT rocket (toasting everything within a kilometer), but we currently cannot launch a fusion powered rocket, so that we cannot argue, place factory in polar orbit because i have a 'god'-mode drive. Lets premise the discussion with a global 'god' commandment that we all can agree on. That progress in space exploration is the target, manned when its appropriate or of benefit, and unmanned at other times. So that neither are we going to restrict one for the other or vice versa. Part 1. Physical Basis I want to use a kind of use a quantum perspective on Earth, we have to argue from a spatial point of view that Earth is a particle with an infinite number of dimensions which define its state, the same argument can be made about the moon. And we need to perform operations on both. If we are to compare it to an atom, the mass being the nucleus and we are electrons or photons that are being effected by its various parameters, depending on the operation. Within the dimensions are qualities (e.g. mu, axial tilt, atmosphere, . . . . .) all defined by dimensions. The reason I want to describe the earth this way is because its not a simple planet rotating on a axis perpendicular to its orbit about the sun so that depending the operation we can select a vector in that space and operate on it to see what happens (so for instance you can use a rotational reference frame, cartesian, change of basis, hamiltonian, etc). The structure is important but details are not until you want to use one then you fabricate the dimensions you want and create vectors). So for instance to assemble a certain set of functions are going to describe how you get information (mass, energy, operations .. . . people) from the Earth to the assembly point and the second how you get mass from the assembly point to an escape. In doing this we can define the energy required to create a particle and then to expel a particle along a desired vector (and all that the expulsion requires). Because of its extended dimensionality and because of this we are sometimes using complex spatial vectors in multiple reference frames. But the desire ulitimately to cross all these frames out and have an orbit to Mars, the Asteroid belt, Jupiter within the common inertial plane of the solar system (we don't have to worry about the galaxy). The math is very complex and I am not going to bore the abstract discussion with that, but just to say there is no perfect plane to go everywhere at everytime. I think everyone already knows this, but its not simply planar problem it is a 4 dimensional problem with other parallels(momentum, acceleration, dM/dt, etc). The broad definition allows us to compute on all operations define local outcomes create a change vector and move to a different system fluidly. Again details are not needed just the framework of testing various models. So the summary here is this. The Earth is a base of information, energy is required to project that into space. In our handwaving dimensional system there are three points. 1. a complex dimensional point denoted QSP-basis, its on the earth, 2. Mission basis, its a facility in space, this is the place were individual missions begin after all components are assembled 3. destination-basis a variable by which you want to go. There are two aspects of this model that are subject to change. 3 does not change, for example the variable Mars is always were mars will be. Once you designate Mars as the destination you, the global operator, cannot change where Mars is. We can dicker over a landing site on Mars, but that is something of submission specific details and for the sake our argument it outside of this thread and in another thread 'Exosystemic Space Stations'. So the concept here is that we have some control over (1) we can manipulate in real time (where we launch from, how much mass, and when within launch window) and likewise we can move (2) anywhere we want but it must be in our planetary system. And so the complexity of the potentials is immediately apparent. Part 2. Logical basis To frame the problem I will create the Query Space Agency .. .QSA, which is of course on Earth, where it is on Earth doesn't matter, but its not at a pole it could be in Russia, Ecuador or Argentina. QSA then has mission objectives. Mars is the default, Moon is a strong second, Asteroid belt is a third, NE-Asteroids are a collective, Venus is an option and Mercury tails the list. Each of these on the list have an ideal dV, which can only be defined in context. To get a feel how part one is essential. For instance lets argue the amount of dV required to get any where in the Solar system is X and that is the minimum required. From that point of view the potential is always realized from the lowest LEO possible and in some case LEO may not be achieved (point 2 is expeditiously removed on your trip to pluto). That is to say, while you are still have notable positive radial velocity remant from your lauch you burn most of the dV required to reach your destination. Ultimately this can be done from the lowest LEO and extracts the most energy from the fuel that the craft gains. Note that we switch to a rotational coordinate system to define radial velocity diagram for the rocket and this allowed us to maximize the Hamiltonian (Hl, lets call it the energy swap thingy KE---> PE KE-PE = SPE). The point we define as the basis is what . . . . . .it evolved during the burn becoming the basis at the end of the burn which the Hl could be predicted for the trip to the LEO, then change of basis and out of the solar system. We could then theoretically just point any rocket at any target in space, fire to lowest dV and we would have the lowest. Actually no, this violates the premise of the argument . . .we do not have a god-mode drive, or a god-mode drag ablation system, god-mode thrust, god-mode visceral fortitude for manned missions. Consequently the time spent in total vertical motion accelerating and fighting drag would consume more dV than making a tangential turn and burning along the tangent outward. This is trivial right? Not exactly, the two statement justify the commencement of missions distal to (1) at some location (2) where drag is not an issue (if you have a craft that is very bulky) and where the burn initiates always along the tangent. The counter argument is why we don't launch all mission from this 'sweetspot' in space, and the answer is most current missionswill have lower specific energy requirement than the sweet spot and can manage within the bulk maximum of primary. Thus (2) by definition is a secondary mission initiation site. In the same way returning an astronaut from the ISS can be seen as part of a different mission than his launch to ISS. So by the logic we can suggest there is a point in space (2) whereby for some manmade objects that are assembled from multiple launches of 1 (cost/risk) is a lower cost/risk than the most efficient launch from earth. The absurd argument is this, we have a function called an 'massive Aerogel' (mass as in huge manifold) in which we are going to use the Aerogel to land something on Mars. But the manifold needs to be formed, so we have a facility in orbit that, say forms the Aerogel and places it on the martian ship, the martian ship takes off and it bounces around on the surface of Mars (what it does on Mars we dont care, like SpaceX launching the fully formed vessel is our mission complete). Anti-god-mode restrictions tell us that we cannot form the Aerogel at Mars and you cant launch the Aerogel rom terra. Part 3. Decision basis. So then we list out all the possible (2) points that can be used for all potential missions inside of our (1->2) basis (contains all missions that are too high for direct, bulky to go direct, or massive to be launched from earth) The minimum dV requiement of each of these is defined along with fuel requirement of crew rotations, station assembly requirements .. . . . .and we get a spatial manifold around Earth at any given time that has one or more minimum. This means we could at some medium future point have several points. Part 4. Evolving (U) exceptional basis (4). The exceptional basis gives us new parameters (4) that we can use for change functions. Lets take an absurd argument. Today every amount of fuel but not power must come from Earth (excepting solar wind, photon push, cannae drives and oberth effects), at somepoint say J2040 we now have power that comes from an asteroid with a comet inside that has undergone system capture (although we care where it is in our system, we don't need to know exactly where it is to create a infinite dimensional state vector for it that can be operated upon, the details can be applied at convenience). This then includes the capture. So for instance the body crosses into the planetary system and then there are operations to capture it and exploit it. Then there are operations to associate its state with other states by association vectors. In associating the exceptional state with all the other (2) states we then begin to reoptimize (2) and indirectly (1) to take advantage of (4), so that (4) and (2) can change (3s never changes since its a target not a waypoint, in this since they are always changing but we never change them). So this is the framework for future technology in space, we work in space for a time and a benefit of this is that the total required-power metric decreases and operations evolve in response to this. The counter argument to this it that exception basis evolves and is not current. This is important to the creative argument, what it means is that any fabrication that assumes that the exception basis is current and not dU4/dt is just like god-mode thrust; its a violation of the constraints. This is not Star Trek you cannot create a transgalactic warp-drive by using Wesley Crusher's best friend experimenting in an engineering lab overnight to suddenly escape the borg. dU4/dt also means that there is a cost involved in the change of state that needs to be applied to other associated systems and that the faster dU4/dt evolves the higher the cost in resources to other aspects. That means that developing an exceptional basis creates a necessary trade off of resources. Here is an example, suppose you are using Space X to supply the transfer and load requirements to an interplanetary shuttle that drops stuff at mars then heads back and reloads. Although you can for instance extract argon from comets its not very efficient and most of the fuel goes to Earth, suddenly now there is a comet in orbit in which a huge amount of hydrogen and oxygen can be produced, so now what you are doing is hauling empty hydrogen tanks back from Mars, but still you need argon gas to route. You can convert to magnesium but theres a cost. In addition to initiate the new system there has to be tanks shipped from Earth, and your argon supply drops off, so the hydrolox tanks build up in Mars orbit. Secondarily manned resources on your station are shifted to the comet and equipment coming from earth is also shifted to the comet. So for a time, as a space tug, your operations slow down as with all operations on your basis (2x). In addition that asteroid or comet is a (3) that is converted to (4) and that conversion has a resource cost before it even reaches the system. This means that missions (2->3x) need to be cancelled and diverted to 2->33->4. The thread is long enough so I will just add a few statements. Although I am still working on the details of how best to use ION drives from Earth orbit, I foresee a best set of circumstances from LEO/MEO. By this I don't mean crazy low LEO, it has to be far enough up where the Sun covers most of the angular displacement * time of a craft in orbit over time. Particular with Solar +prograde exit vectors the burn optimum is beyond termination the Earth this means to expose the craft while burning the craft has to be significantly high or have lightweight and efficient batteries. The mass efficiency comes from the differential between chemical Ve (4700) and ION drive Ve (>30000) that, in essence you do not want to use chemical reaction energy propellants to push an ION drive with bulky solar panels. The point however I want to make that it is possible to use ION thrusters during most of the orbit without loosing dV as long as certain parameters are preserved (IOW not a continous spiral) and also it might be faster to do this than a spiral. So that even a weakly powered ION drive has some modifyers that can get it out of Earth orbit faster (for example using highest ISP thrust for some operations and lowest ISP thrust for others, such as at the rmin in an orbit or when making the final kick. The direction of thrust can be varied to keep the rmin optimal and even reversed at highest possible ISP (or even a photon drive). OTOH the orbitally-static stations are attractive in the sense that we can always have them in a state that is optimal for most outgoing vectors. The problem that I don't like about these is they generally are 4000dV vectors at Ve of 5000 or lower. I cannot see ION drives doing this thing since their best benefit is in the kick from the LEO/MEO Earth to its destination, and in actuality tolerates super-Hohmann transfers that markedly shorten time. But there are time constraints on some missions so crawling out of L/MEO to L2 may be the best means of doing this, and certainly saves alot of dV on ION-IP shuttles. The problem is that for an ION drive once you are at L2, you are no longer required, and if PL need to use L2 to use your thrust is really not of a benefit in the PL to L2 transfer. It could be of some benefit, perhaps a smaller number of kicks where solar (minimal) and ion contribute to the kick over say 2 days. The simple problem is that ION drives would be really really useful if they had more thrust and of course that requires a power supply that we don't have. If we keep in mind that energy maximization is all about dV @ V this means that if orbital minimum is a 6531 m its V = 7812 m/s and 5523 m/s at 13063 km. For each amount of fuel burnt at gives a change of energy of 7812/dV at 7812 and 5523/dV at 5523. This goes to 12000E/dv at and somewhat less than 11500E/dv for the starting 5523. Again so there is basically a loss of 1500E/dv by doubling the radius. Thats a heavy tax to pay in addition to circularization costs. But it increase the burn span by almost 80 degrees. Of course as the orbit expands you issues with timing of optimal burns that cannot be circumvented so it might be wise to thrust up the Drives by changing the grid voltage and increasing amps. The final comment involves the shuttle and its potential application to the problem that has been de-optioned. Most of the gateways are programs and are fixed in nature, therefore if program flaws occur there is essentially little change options. With a shuttle based assembly the assembly states can change, since the initial state X is only in a place where shuttle can reach, if the X assembly point then spawns other Xs the shuttle is no longer required, however inefficient it might be its functionality could be leveraged into other states, and those states would make the shuttle obsolete, which is desired.

Heat it up before you expel it, more modern towers have improved heavy gas removal systems. The reports conclusion was that the primary orbiter damage was cause by an Srb hitting and separating the right wing. But at the same time the orbiter was enveloped in a shroud of RCS which means that the RCS was also involved, this obviousl was liberated by the impact. They don't believe that the red tank was involved in the disintegration because by the time the h2 had ignited it appears that the upper orbiter had separated. I doesn't really change the conclusion, but again if the SRB can hit the right wing it can also hit the crew escape module, having the SRBs able to range vectors in the direction of the orbiter is a bad thing made worse by a no-abort mode on the SRB. The true fail safe would have been to kill the orbiters engine and break from ET and pray, still I don't think it would have translocated horizontally fast enough to prevent wing damage, but maybe preserve RCS burn and that would have been something. The diagnosis showed that the crew hatch worked but was never opened, no one tried to escape, you might have better luck hitting the water at terminal velocity than in an orbiter at terminal velocity, particularly if you could use your uniform to slow down. The final conclusion does not remark upon anything but the Right SRB.

Yeah but thats trivial, sorry, but after 133 flights and 30 years the VAB should have been booked (depreciated) and funds allocated for a newer VAB. I have no problem with replacement crewed repair and build facilities, but the way I look at it those designs are about 20 years too late. You can't complain, NASA works like the US military at times, they should have had a better head for business and again if you had soldiers in the field dealing with falling ice, you could almost bet that mothers and sisters back home would be screaming at their congressmen to hire a contractor that will fix the problem, thats what happened with the humvie and after about 7 years they had a replacement. The relationship between contractor and contractee is too cozy. You have a problem like that and you take bids from others that commit to fix the problem . . .Were we married to the big orange tank? This of course doomed the shuttle.

Yes we can talk about these. But first the shuttle was effectively designed in 1977, 40 years ago, and there is no expectation that in a break-thru industry that a single design should last 40 years. But the RL-10s design is basically the same a expansion cycle cryogenic engine since 1960, that is 57 years. The difference here is that the RL-10 is a component of a system (like an RS232 analog serial connection) and the shuttle is the system. Evolved systems should improve both performance and safety, no doubt and there is plenty of room for replacement. For example pilots could be replaced with flight computers that are controlled via generic commands (like change orbit, or controlled from encrypted ground commands). So get the crew down from 7 to say four. Remove certain functions, get rid of the ISS rescue functions and you have a much smaller crew compartment, more payload, potentially. In hindsite while it seem great that it could carry 7 one has to wonder why it needed to carry many. LV risk should be low as feasibly possible, launch failures waste time and are diseconomies that must be avoided. IN terms of risk you can't really say we will tolerate this risk but not that, risk should come down where its the highest and again this is created by the launch. If tiles are popping off in orbit or reentry because some latent factor in shuttle age, its a problem. Risk reduction is multifaceted, it does not need to be this or that, it can be this and that and achieve the same result for a lower cost. First cost and risk mitigating issue is if you don't need a multifaceted vehicle and 7 nauts for a mission, why do it. Use a less risky vehicle that takes fewer nauts. Problem solved. But the _and_ remediation issues goes further, why after 30 years do we still need pilots on the missions when dragon clearly shows that certain manned missions are functionally redundant with already available missions. Right there we remove 2/3rds of the human risk. As stated before you don't need nauts to release a Hubble, you can have automated space craft (and actually ion driven level craft can do this much more efficiently) retrieving dead packages and deorbiting them. Even if the ion drive cannot deliver them home it could deliever them to a basket mounted on the ISS where they could potentially be converted to crucial and disposable components, some returned with dragon and others deorbited as waste. BY the same token (a topic of a different thread) certain functions of the shuttle could have been spaced base. If we can imagine a model were the shuttle builds X and then X0 builds X1, X2, . . .XN then ceasing the shuttles function before X was complete economically and temporally unwise. The contractors for the DSG and the cryostation I don't trust to do the job. Yep, I think if you put a bunch of highschool students in a garage with a snow machine and a mock up of the ET they could probably come up with a solution, Sticky saran wrap on the surface that peeled away in two pieces in the seconds before the launch could have pulled all the little icebergs off the shuttle and the tiles could have been protected. Even better there are things that prevent ice from solifying and remain as a powder. It was a silly problem that NASA and its contractors stumbled over.

That model would work if it was pointed with a -radial direction such as it would free itself, but you have two dead crew members on the flight deck. BTW the shuttle was designed, in an emergency to evacuate 11 crew members. Then don't say it. The cabin apparently depressurized. Since the cabins pressure is through the tail of the craft, if you strip this before the valves close or jeapardize the switches then the cabin vents. SO a depressurization of the cabin is a compromise of the cabin also. More than that, the orbiter was designed to land as it fail-safe option, if that is disable, then the whole can be considered disabled. Again we can except bugs, like the image in the posts above. That considerably alters the function and performance of the orbiter.

At least there is one person here thinking about the evolution argument, but in my opinion (n dealing with other posts and getting back to this one at the end) its not about the crew release. Biologically speaking the source of the problem also has to mandate the solution, not the 3rd dependent reaction. As you state the shuttles capabilities are exceptional, just not as efficient as desired. I say biologically because FIRST the crew has to be in a conscious or mobile state. You can't argue success if three were already unconscious as the moment of force application is completed. So if the state of the system evolves too quickly no crew compartment is going to work thoroughly and if the solution is not going to be complete there is no reason to waste mass to remediate the problem. The problem with the evolution of the STS-51-L is that there was a state that could no longer be contained. Even if one person was conscious there was no way for him to protect the rest of the crew from the effects of decompression, there was no way to alter the shuttles trajectory (other than one-human unit movements) because all of the control features disintegrated. Before we can discuss saving the crew (both in the case of challenger and columbia) we first have to save the orbiter. If the orbiter is significantly torqued to its disintegration point then its likely you already have dead or nearly dead crew. This is my interpretation of what happened. There was a pressure breach people went for their O2 but there was no means to escape or the crew were not able to escape due to structural criticality. Unless we are talking about launch crew in a 'bug' that they then move to the orbiter after a certain stage is released, there are basically no solutions to this problem. So 7PF does have a minimal point, but then the next flight of the Soyuz could show us a design flaw in their system. Challenger disaster should not have happened and it was 100% preventable, this does not mean by some other mechanism a similar crisis could occur, but that was the negligent homicide of the crew, a crime that was never prosecuted. If it had been prosecuted our view of the incident may be completely different. Because it wasn't we look at flaws in a system that in reality worked as designed, you don't drive a car off a cliff and say the brakes are broken and you couldn't stop; the time to test brakes is before going over the side of cliff. That is the initial problem but let me take the devil's advocate and argue that it could have been a completely random occurrence. Im doing this to develop a structural argument for manned space flight that eliminates certain models (i.e the above). So we have to define the what that state was then work to correct it. The initial state is a booster who nominal performance evolved over time along an 'unexpected' tangent (literally there was a tangent exhaust vector to the axial vector) . That tangent interfered with the containment function of the hydrolox tank. There was a domino effect on performance that went critical and standard models of prediction break down because there are forces acting in many directions and damage becomes foggy. So here we have to stop and argue, there is a theoretical crew escape system that would have work, it could be explosive bolts on the crew compartment with a hidden parachute that drops them safely in the Atlantic, the pointy nose should mitigation the impact deceleration. SO we have a handwaving solution. We assume that would stay alive long enough for them to catch their breath or be aided by a crew member. The problem is this you have torque being applied on two lift surfaces differentially to the point at least one breaks, that torque commutes up the craft and before the bolts blow its now compromised the craft. The main engines are still in a declining burn the nose is under Q and the compartment cannot run from the orbiter, its stuck until all thrust go to zero. You can't really modify the orbiters outcome until you deal with the torque issues, and you cant deal with that until you deal with the structural issues on the tank (its liquid oxygen and hydrogen that want nothing more than to bypass the engines and burn). Yes, the orbiter is too close to the tanks, but both are too close to the SRBs that really have a design flaw, the joints. But for the sake of our random argument lets only consider the functions. The function of an SRB is only to burn, thats it you strike a match and stuff shoots out the back (it applies to all SRB designs). The function of the Red tank was not to burn; it was a fuel supply and so all the forces intrinsic to itself can be prevented. Of course, the orbiter engines can explode, but then there are limitations on the fuel they have access to and thus torque they can produce. There have been several RS-25 failures of these type and none jeopardized the mission. We have to look at the problem logically, we need oxygen and fuel in space, so we can't be so afraid of these things that we never take them. We can have 10 levels of switches on them such they will always be shut off from threat generation. So all our disintegration thrust vectors are tied to the red tank and attached boosters. There are situations were the red tank could have otherwise failed, there could have been a failing of a joint it could have suffered Q damage, etc. But then the next step is that the hydrolox would ignite, OK we need at a spark or lightning, and then on top of that we need some mixing torque to get that 'boom' required to disintigtate the orbiter. So we have an If and If and IF and then construct. Whereas the booster burned a whole through the tank and directly ignited the hydrogen, it circumvented two of the Ifs in a single step and we dont need and electrical spark. So the probability of the Red tank, in and of itself, triggering the orbiter's fate is much lower than if the booster does it. We can't definitely know how low because we have to cross parameters like when is max Q, when is the most force applied from the boosters . . . . . but needless to say there is a time constraint on when intrinsic forces can occur. And by and large Q is known and F is known and in aircraft these failures are pretty rare (Aloha airlines 737 is the last incident I remember, and the Corsair incident was another set). This thread really should be about SRBs. WE know about the link of structural failure of the orbiter and random booster malfunction (again we are assuming that this could ever happened inside the rating and that the probability is ~<1/133). OK then what is the correct course. So i have to correct one thing I said, the boosters do produce more thrust, but the main engine produce more thrust * time than the booster produces. As a result the boosters are not the main source of thrust or energy and certainly not the main source of acceleration. Hydrolox has almost twice the Ve of solid fuels. Therefore boosters are replaceable. And if they are replaceable and are creating excessive risk they should be replaced. But I would argue one other thing, to the ISP of the boosters is not impressive, we have newer launch systems that have better ISP are more tolerant of single engine failure (since they have nine engines) can be more easily recycled AND can be throttled off in case of an emergency in their operations. So given that why use SRBs on manned missions? The next logic here is that for any system where the booster is close to the orbiter or crew compartment, should we be using solid fuels? So what about mounting SRBS (several way down the red tank, the problem with that if they break the fastening they can slam into the orbiter which is above it and they cannot stop propelling themselves. So in the model above as drawn and any of its still it does not circumvent the critique because essentially the SRBs can compromise any structure if they are mounted far enough away from the core and dont have active steering functions. Consequently all designs with SRBs are to be considered maybe economical but too risky. Speaking of risk, we are in shelter in place, again. Last fall we had Harvey, its already snowed once in December and now, apparently, in good ole East Texas, we are having an ice-storm . . Yeah!!! climate change. But to be honest the shelter in place comes from the fact that we down-here lack the ice-driving functions in the brain.

Thanks but no thanks, it does not meet any useful requirments.

MISSE-8 was deployed but nauts and retrieved by nauts on EVA. its <500kg so basically its compact enough to be moved by man . . . .but not to argue the point, for most cases this will suffice.

If the monitoring space ship is not generating the radio waves then its passive. You can also use frequency modulation to make it difficult to locate the source. But then the other problem is that with a big hairy 'top' shaped shield how does one detect the waves passing through that. Anyway I think its active defense not passive, my bets are that it is a weapon. But to answer 1 question, at 51 degrees (sin 51 = 0.777) X extends the center of its range another 700 miles north, and this covers most of Russia.

It would be nice if we had something, anything. MOre vaporware

I cropped this from the video and found its source online http://hubski.com/pub/399315 " This was a quote from a government official who had a kind of a queer smile in the corner of her mouth when she said it, its one of the slip things, like people shaking their head "no" when they are lying.

The shuttle help build the ISS and the ISS took over some of its function and it was merely a matter of transporting people on the cheapest/safest launch system you could afford, since RSA was a partner this gave them some skin in the game, while the US designed whatever NASA had in store. The SpaceX delivery system can be seen as part of the test. In this way part of the shuttles mission is complete . So now the proper question what if we never have anything like the shuttle again (by like I mean capable of performing at least one of its currently diminished functions). Given we have already discussed material testing and the limitations. And a particularly shrewd individual could come up with a mini-test that an astronaut could take off the ISS, put on the side of the ISS for 2 years, after two years wrap a plastic around it, fill it with helium as pressure equilibrates to internal ISS pressure and then bring it back to Earth on the next soyuz mission. This can be done, but satellites will not be issued for material studies in the foreseeable future. Of course if spaceX has a crew vehicle and the ISS rotations are 3 on, 3 off, then we don't need the shuttle crew compartment. And if SX can come up with a 1 or 2 man repair platform then we don;'t need the famous shuttle arm or cargo bay for repairing stuff. So would we have all the functions covered . . . . . .no. Suppose you want to start assembling bulky stuff in space. Things that have huge floppy solar panels that would be difficult to deploy without some assist, what then. So I designed a factory for building spacecraft and while I can launch the factory from Earth its a kT to orbit, so its bigger than any payload lifted. So the alternative is to assemble in space. And the way it works is each assembly has a set of holes with wires feeding through pressurized tubes. You assemble the wires for the section with a double bolt connector, and then once every thing is in the matrix, the wires are tightened drawing the pieces together. and from the outside these thing are finally torqued until the rubber seals catch. Someone on the inside then bolts the pieces little by little together (the bolt sections are wide and have double seals so that we don't have to worry about leaking. And eventually the pieces are one solid unit, the wires are loosened and re-tighten from the outside. The factory at its middle has a large hinged door so that it can be closed for safety reasons, its wide, larger than 5 meters, and theoretically you could apply some pressure to make it easier to control motion inside factor, but not enough to breath. The door hinges would be mounted to the solid assembly bottom plate and then the door mounted and the craft is the factor and other things can be docked to this. Although not alot of this work is outside, the scaffolding stuff is almost entirely out of the ship, this is something were you might robotic drones capable of positioning and holding positions and then a few human hands to take over when the bots could not perform. And this all basically needs a cargo bay (for the assembly robots) and some sort of robotic arm to grab a reference piece for which torque can be applied. etc. So why have a factory. The question of a factory really reached the point about range. we could project a human to anywhere in the outer solar system from LEO right now, but getting them into a gravity well change the SME significantly (such as landing) and out again is a problem. Its not a small problem, its one of the biggest problem NASA faces for manned missions to Mars. We know that we can have these fantastic ISPs with ION drives, but we don't have a power supply, and so this is the problem. There are two fronts to solve this problem, one is to have a fusion reactor and some power conversion (heat to elec) and this means the reactor (by itself the heaviest PL ever put in space) and a frame with a cooling system attached, and the more you want to cool the more spread-out these need to be. But that is far future stuff so we don't have to worry about it. And so the second is Solar power ION. And so we need some new age panels (Ion/magnetic storm resistant) and we need a scaffold many time longer than the longest spaceship ever put into orbit. So this then needs something to connect in space, and so in my factor design the core is added scaffolding, and then the Cargo unit and pushed out where panels are added as it exits the orifice, and then finally the lagging scaffolding and then the solar panels, and its good to pick up cargo and fuel. And so that is a logic for having a mobile station that can provide assembly support. This is to say, what progress is NASA making beyond the ISS that is actually in space and something more than docked modules, what are its current off-ISS complex assembly capabilities. You mean vapor ware.

The logic is kind of corrupt. You cannot plan a material test if you have no means to bring it back to Earth. There are a variety of new materials develope since the last material test was concluded that will never be tested in space because of the extreme difficulty in bring them back without a shuttle. You could do them outside the space station, that would require 2 space walks and the size of the test would be limited to what an astronaut can safely take and mount in space. The shuttle conducted several of these during its tenure.

I love the beginning, Its the cannae drive!!!!!!!!

I never said they had to keep the shuttle, but one has to what there motives were for abruptly ceasing certain functions. They clearly have dropped the ball, and Orion is unlikely to be a suitable replacement. It will be cancelled at some point because of time delays and cost overruns.

Not to worry, while they are dropping the ball on manned space flight, SpaceX will pick it up soon enough.

Im choosing that NASA should perform an extension of function over time over abdication of function for more than a decade.