NASA to build Saturn VI (in-line SDLV)

[najab]

><i>I can't see why it wouldn't be used for the SRB Launcher.</i><p>Because the additional thrust might be too much!</p>

 

[gladiator1332]

There are ways to solve that. When I brought the SRB Launcher up on the Orbiter Space Sim Forum awhile back, someone had this to say:<br /><br />"You really don't need diffrent propellants what you need is a diffrent gometry for the central opening. A star or asterix shaped central opening will give you a high initial thrust, but as the walls of the central chamber get burned up to a more circular configuration the thrust will bottom out and remain steady till burnout.<br /><br />check it out here www.braeunig.us/space/propuls.htm#geometry<br /><br />You should find a geometry that will satisfy a manned launch, that will not cause to much stress on an astronaut."<br /><br />And also:<br /><br />"An SRB burns from the centre out. That is to say an SRB is like a packet of polos, with the exposed central surface being the bit that burns. If that surface is circular, the minimum area is exposed. If that surface is indented (like a star) then more area of fuel is exposed, hence it burns faster and the thrust is higher.<br /><br />Uppon further evaluation of The forces on a person. A solid fuel configuration of iether; the cruciform, or double anchor form would be the best, with the double anchor being the most desireable. A person will feel that the thrust suddenly stops with the double anchor geometry upon burnout. This is a seat of the pants way to notify the astronauts of staging when all comunications with ground are interupted or out."<br /><br />

 

[najab]

Yeah, but this isn't weather we're talking about, it's climate. I can tell you haven't spent much time in Florida - ask <b>any</b> Floridian what they expect the weather to be at 1500 on a summer day - and they'll laugh and say "That's easy - it'll be raining, just stopped raining or just about to rain. Oh, and lightning."

 

[henryhallam]

<font color="yellow"><br />I am very sure that we will attempt a launch on July 13.<br /></font><br /><br />Do you think the ECO sensor box problem for STS-300 has been resolved then? I hope so!

 

[najab]

Yeah, they could use more inhibitor in the first few seconds of the burn profile, but there's only so far that can take you - no matter how you shape it the additional segment means surface area which means more thrust late in the burn.

 

[starfhury]

Thanks SG.<br /><br />I'm pretty sure I'll be there for the launch if it happens within the 3 days before any stand down. <div class="Discussion_UserSignature"> </div>

 

[lunatio_gordin]

Orbiter's great, but my computer doesn't have a joystick port anymore. i had a masssive solar system.

 

[drwayne]

It is actually amazing what *can* make it out of the nozzle. I've seen imagery of chuffing that - well - they are big pieces of ...fuel.<br /><br /><img src="/images/icons/smile.gif" /><br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[spacester]

What a great time to be a space geek!<br /><br />OK I’m ready to make my predictions before we find out the truth over the ensuing weeks. <img src="/images/icons/laugh.gif" /><br /><br />My hero Mike Griffin gets the big hardware up with his Inline SDHLV. He allows private, American-Led efforts to rent rides at low cost.<br /><br />Shuttle retires in mid 2010, with the exception of a single orbiter flying one mission a year or so for the next 5 years or so. Atlantis, I would presume.<br /><br />NASA assures the US government an in-sourced capability to rotate crew before the Shuttle pre-retires. They do this with a CEV on top of a SRB Stick, most likely reusable. The CEV will have the capability to change out 8 people on ISS at a time.<br /><br />Both of the new NASA rockets are equipped with awesome second stages. Using engines available today, they will place the payload either up above the bulk of the space junk in a high LEO, or fly direct ascent to Moon or Mars. The initial CEV will have the capability to return NASA to the Moon but won't be configured to do so at first. With the boost to cis-lunar transfer provided by the second stage, it will be able to return to Earth surface via lunar surface on its own. If flying from ISS, it will be able to orbit Luna and return on its own. Re-prop operations allow landing.<br /><br />Meanwhile, ISS crew exchange will shift to commercial rides on the t/space CXV and the other orbital tourism outfit that succeeds. The CEV will be configured for extended missions using lunar orbit re-prop operations. The CEV will follow the sun and explore the far side. It will support infrastructure development on the surface.<br /><br />Also meanwhile, private operations begin on the Moon and are utilizing the infrastructure improvements provided by NASA’s operations. In turn, they offer certain amenities and logistical options for NASA’s personnel.<br /><br />Starting from here I’m hoping more than predicting.<br /><br />Someone noticed that these awesome s <div class="Discussion_UserSignature"> </div>

 

[yree]

Reliability and Crew Safety Assessment<br />for<br />Solid Rocket Booster / J-2S Based<br />Launch Vehicle<br /><br />http://www.boom.net/~jake/atk_docs/ATK_Thiokol_SRB.J_2S_PRA.pdf

 

[yree]

5/22/2005 GRIFFIN'S DRIVE FOR SHUTTLE-DERIVED<br /><br />Shuttle Derived Concepts (ATK Thiokol)In recent weeks it has become clear that Michael Griffin, NASA's new Administrator, is maneuvering to win support for development of a new series of "shuttle-derived" launchers. By stating that he expected the Crew Exploration Vehicle (CEV) launch mass to grow beyond the capabilities of any existing launch vehicle, Griffin effectively leveled the playing field between shuttle-derived and Evolved Expendable Launch Vehicle (EELV) options.<br /><br />In early May, in a speech at a meeting of Women in Aerospace, Griffin said that the Project Constellation CEV should weigh no less than about 30 metric tons, more weight than could be carried by any vehicle available to launch it today. Previously, NASA's CEV requirements had called for a launch mass not to exceed 20 metric tons, a weight that could be launched by current EELV (Boeing Delta IV and Lockheed Martin Atlas V) designs.<br /><br />On May 18, in a statement before a U.S. Senate subcommittee, Griffin mentioned two possible paths toward development of a CEV launch vehicle. The first path would be to develop a launch system derived from the Shuttle components, specifically a single Solid Rocket Booster (SRB) topped by a new upper stage. The second option would be to upgrade the EELV heavy-lift designs, an effort that he said would also require development of a new upper stage.<br /><br />During the same presentation, Griffin reiterated his previous commitments to both retire Shuttle in 2010 and to revise the CEV program to make the new spacecraft available soon after the Shuttle retires so that it could perform International Space Station (ISS) support missions. With these commitments, Griffin deftly added a sense of urgency to the CEV program - an urgency that seems intended to leverage Congressional support for shuttle-derived launch vehicle development.<br /><br />Griffin told the subcommittee that, "a key aspect of the Agency's

 

[drwayne]

"The Apollo spacecraft that were used to perform earth orbital missions weighed roughly 15-20 tons."<br /><br />Note that Apollo was not designed for the orbital mission, so it was neccessarily overweight for it.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[yree]

NASA Administrator Mike Griffin<br />Remarks to the Space Transportation Association1<br />Washington, D.C. – Tuesday, June 21, 2005<br />http://www.nasa.gov/pdf/119275main_Griffin_STA_21_June_2005.pdf

 

[cdr6]

Good analogy with the ATT thing...<br /><br />Personnaly, I'm pulling for Biglow. That night night back in 69 (Viet Nam) when I sat on on a bunker on guard duty looking up at the moon just awe struck that we were actually there. I thought sure by now we'd have a hotel in orbit for us tourist types, (sigh) t'was not to be. <br /><br />The whole launch thing is like some prepostrious Gordian Knot. The little guys have the drive but not the ability, and the big guys have the ability but not the drive. Where is alexander the great when you need him?<br /><br />It's like the Mars Guru says, "This is the only mode of transportation based on artillery." (Sorry the name escapes me, but he's the head of the Mars Society...) <br /><br />Unfortuneately untill we can beat this "rocket" thing with some kind of aerospace plane/airborne launcher, we are stuck with the high cost of manufactureability and horrendious tooling costs. (It doesn't look like I'm going to get my LEO vacation.)<br /><br />Knocking around the aerospace industry for most of adult life I am firmly of the opinnion that the big guys Boeing and Lockheed have the ability using "existing technology" to put forth a commerical manned space vehicle. <br /><br />(Imagine if you will six skylab vehicles hubbed together, four opposed and two on axis, housing and recreation for up to 48 folks.)

 

[grooble]

It still isn't enough though. I don't see how sending a few dozen folks makes us a spacefaring civilisation. That won't be true until millions go into space routinely and cheaply.<br /><br />There needs to be 1000s of multiple-hundreds carrying space Aircraft.<br /><br />You'll never get millions up from rockets, i mean look how long it takes just to get 1 launch these days.<br /><br />

 

[yree]

COUNTDOWN TO DISCOVERY: AN OCCASIONAL SERIES ON NASA'S RETURN TO FLIGHT<br />Shuttle components could be used in next generation of rockets<br />APE CANAVERAL -- Discovery's planned launch next month will mark the beginning of the end of the space-shuttle program, but parts of the rocket could help propel astronauts to the moon and beyond long after the current fleet of ships is retired.<br /><br />Once the plane-like orbiters are mothballed in 2010, boosters from the shuttle's propulsion systems might be used to power lunar missions as well as flights to the international space station.<br /><br />In the Apollo era, a single launch of the giant Saturn 5 rocket carried to orbit everything needed for a moon expedition: a lunar lander, crew module and service module that provided propulsion and power. A similar approach today would require another vehicle capable of lifting huge amounts of hardware.<br /><br />The likely solution: launchers created from parts of the so-called shuttle stack that includes the external fuel tank and twin solid rocket boosters.<br /><br />"We talk about retiring the space shuttle. What is really meant is that we need to retire the space-shuttle orbiter," NASA Administrator Michael Griffin told Congress recently. "If I remove the orbiter and put on a cargo module, I have a heavy lifter."<br /><br />A shuttle-derived booster would have lots of advantages besides its ability as a heavy lifter.<br /><br />The shuttle's components are considered safe for human missions. Many of the facilities to build, process and launch a new vehicle already are in place. The time required to develop a shuttle-based booster would be a relatively short four to five years. Many shuttle workers at places such as Kennedy Space Center could continue on in the new effort.<br /><br />"The shuttle-derived answer is significantly better in terms of the work force at the Cape [Canaveral]," said Steve Oswald, a former astronaut and Boeing vice president who heads the company's shuttle

 

[henryhallam]

<font color="yellow"><br />APE CANAVERAL<br /></font><br /><br />I'm sure that's what old Ham used to call it...

 

[spacester]

Poor poor Ham. One of the tragic stories of space flight . . . yeah, he was just a monkey, but he deserved better. Off topic, sorry. Maybe a new thread? <div class="Discussion_UserSignature"> </div>

 

[gladiator1332]

I really hope Griffin doesn't buckle under the pressure from the Air Force. I agree with everything he said to the Congress, as I too want to see the Shuttle retired, but I still believe the rest of the system without the Orbiter provides the perfect launch vehicle. <br />Of course Boeing and the Air Froce want NASA to go with the D4, there is no real market for the D4H, so Boeing is counting on NASA launches. The pickel they are in is the exact reason why Lockheed never developed the Atlas V Heavy. <br />And just for a small launch to LEO, to put the CEV in orbit, you are going to need to upgrade a Delta IV Heavy which already has two CCBs, when instead you could have launched the same amount with a single SRB with an upperstage. <br /><br />Another thing to consider. How many Delta 4 Heavy's can you assemble in the VAB at one time? I am guessing only one. Think of how many SRB Launchers you can assemble. Two SRBs are stacked every shuttle launch. I bet at least 3 or 4 SRB Launchers can be assembled all at the same time. This will deffinatly speed things up when it comes time for launch. <br /><br />The SRB is already manrated, it has beenn used on manned vehicles for the last 24 years, however, the Air Force wants NASA to choose a vehicle that has had one launch in it Heavy configuration, a launch that did not go 100% as planned. Boeing called it a success, but many questioned this. <br /><br />Right now, the D4H is just one launch ahead of Rutan and T/Space, who have 0 launches with their vehicle. If that record could not be trusted, how can we trust the D4? <br /><br />I trust that Griffin will make the right choice, and I think he will see it like many do, that Shuttle Derived Heavy Lift, and the SRB Launcher are the way to go.

 

[mrmorris]

<font color="yellow">"... I still believe the rest of the system without the Orbiter provides the perfect launch vehicle. "</font><br /><br />Perfect? Not likely. How about "the optimum LV alternative given budgetary necessities, time constraints, and political realities". <img src="/images/icons/smile.gif" />

 

[strandedonearth]

I keep hearing how the rumble of the SRB's give the Orbiter a somewhat rough ride. Wouldn't the ride on a single-stick launcher be rougher without the mass of the ET and Orbiter to help smooth out the rumble? Much like the flywheel in a car smoothes out the power pulses from the engine? Or would the upper stage and CEV have enough mass to have the same effect?

 

[henryhallam]

Considering that the acceleration profile will be much the same, and of course you only have one SRB rather than two, this suggests to me that to a certain extent, the mass of the upper stage and spacecraft would be enough to "mimic" an ordinary Shuttle launch from the SRB's point of view. So I would suspect that you'll still get some damping. The ride will probably be a bit rougher than a standard shuttle launch due to all the thrust coming from the SRB rather than just most of it, but my guess is it won't be too dramatic a difference.<br /><br />I'm not a rocket scientist so don't take my word for it!

 

[mrmorris]

<font color="yellow">"...this suggests to me that to a certain extent, the mass of the upper stage and spacecraft would be enough to "mimic" an ordinary Shuttle launch from the SRB's point of view. "</font><br /><br />This is what I was thinking as well, so I decided to do some voodoo math crunching of figures. Unfortunately, I can't get to Astronautix right now (getting a DNS error) so had to make do with Googled sources I trust less.<br /><br />Looking up the mass on Endeaver and payloads, I get:<br /><br />Endeavor: ~100,000 kg<br />Payload: ~25,000 kg<br /><br />So at full loadout there's about 125,000 kg being shared between two SRBs plus the SSMEs.<br /><br />Three SSMEs provide ~700,000 kgf <br />Each SRB provides ~1,175,000 kgf<br /><br />Therefore ~23% of the thrust comes from the SSMEs during the initial ascent. Performing some voodoo math, that would mean the equivalent mass being lifted by the SRBs alone would be 125,000kg * .77 or 96,250kg. Each SRB then would be lifting a mass of ~48,125kg.<br /><br />We're talking about lifting a spacecraft of 24,000kg to orbit. Therefore, if the amount of mass for the upper stage of the stick is in the realm of 24,125kg, then the profile would be pretty much like what the SRBs do now. It's hard to guess what the upper stage would mass (especially without astronautix), but 24,000 kg doesn't seem like an unreasonable guesstimate.

 

[najab]

There's one little thing you forgot in your calculations - the million pounds of prop in the ET. <img src="/images/icons/smile.gif" />

 

[mrmorris]

<font color="yellow">"...the million pounds of prop in the ET."</font><br /><br />Hmmm. Can't we just assume that's mass-free? <br /><br />No? <br /><br /><br />Dang!