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Space Forum / Shuttle / March 2008A question about LFBBs
Would it make any difference if you didn't care if they returned to the launch site vs. just being retrievable? Like say a TAL flight? Benefits, drawbacks? Also, how likely was it that the copy of Bill Gerstenmaier that jogged past me on the beach a couple miles south of the port wearing an STS-1 t-shirt was the original?  SignatureThis is a siggy | To E-mail, do note | Just because something It's properly formatted | who you mean to reply-to | is possible, doesn't No person, none, care | and it will reach me | mean it can happen > Would it make any difference if you didn't care if they returned to the > launch site vs. just being retrievable? �Like say a TAL flight? �Benefits, [quoted text clipped - 7 lines] > It's properly formatted | who you mean to reply-to | �is possible, doesn't > No person, none, care � | � and it will reach me � | � mean it can happen fly back to launch site much better than dropping in the ocean, salt water is tough on everything > Would it make any difference if you didn't care if they returned to the > launch site vs. just being retrievable? Like say a TAL flight? Benefits, > drawbacks? Possibly, but I'd think that a TAL flight would be awfully far downrange for a typical first stage recovery operation. The trouble with this approach is you need several first stage recovery sites if you're going to launch to different inclinations. This starts to drive up fixed costs if every recovery site needs special equipment to handle the landing of the first stage. A better approach might be to return to the launch site by having the first stage launch essentially straight up. Sure, the second stage takes a bit of a performance hit since the first stage didn't give it any additional horizontal velocity (compared to an "optimal" two stage launch vehicle), but so what? If it makes recovery of the first stage a lot easier, it might be well worth the trouble for the second stage. A bonus for the first stage launching straight up is that this approach works well for varying inclinations since the first stage always comes down at the launch site. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein > A better approach might be to return to the launch site by having the first > stage launch essentially straight up. Sure, the second stage takes a bit of > a performance hit since the first stage didn't give it any additional > horizontal velocity (compared to an "optimal" two stage launch vehicle), I would suspect "a bit of a hit" would be a fairly major understatement. Since orbit is all about horizontal speed, I suspect that it would be a major hit. A lot of fuel would be expanded to raise the stack without giving it any horizontal speed. Once the LFBBs are expanded, the stack would have 0 horizontal speed and would then need to use its second stage to do 100% of the acceleration needed to reach orbital speed. The only advantage is that the second stage would start off at a higher altitude with less drag from atmosphere. > > A better approach might be to return to the launch site by having the first > > stage launch essentially straight up. �Sure, the second stage takes a bit of [quoted text clipped - 11 lines] > The only advantage is that the second stage would start off at a higher > altitude with less drag from atmosphere. LFBB with wings could fly back to launch site >> A better approach might be to return to the launch site by having the >> first [quoted text clipped - 13 lines] > The only advantage is that the second stage would start off at a higher > altitude with less drag from atmosphere. Exactly, but that's still an advantage since the upper stage can use engines optimized for vacuum (higher expansion ratio, and higher ISP without resorting to super high chamber pressures like the SSME). The up and down first stage becomes easier to design and build since things like cross-range become a non-issue. You can even go with a VTVL reusable first stage since you don't really need things like wings anymore. Certainly the size of the overall vehicle may be bigger than a TSTO with "optimal" staging. However, this approach drives the complexity of the first stage down and the cost to design and build something like this scales more closely with complexity than with size. To me, this would be a very rational approach to take if you wanted to build a launch vehicle with a reusable first stage with an expendable second stage. It lets you gain experience with reusability while reducing a lot of the risk since this approach makes the reusable first stage design easier. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein > Possibly, but I'd think that a TAL flight would be awfully far downrange for > a typical first stage recovery operation. The trouble with this approach is > you need several first stage recovery sites if you're going to launch to > different inclinations. This starts to drive up fixed costs if every > recovery site needs special equipment to handle the landing of the first > stage. This argument isn't very convincing given we don't have much of a problem with finding shuttle abort sites, but then I suppose you could say we don't use them every launch. I guess I'm just fixated on the "flyback" aspect, and wonder if you couldn't gain some things by not insisting on returning to the launch site, since I imagine that places some restrictions on size and speed. SignatureThis is a siggy | To E-mail, do note | Just because something It's properly formatted | who you mean to reply-to | is possible, doesn't No person, none, care | and it will reach me | mean it can happen >> Possibly, but I'd think that a TAL flight would be awfully far downrange >> for [quoted text clipped - 10 lines] > them > every launch. Actually it is. One of the reasons that TAL sites are acessible is the shuttle's relatively large cross-range. But that cross-range comes at a higher development and operational price than a vehicle without that high cross-range requirement. > I guess I'm just fixated on the "flyback" aspect, and wonder if you > couldn't > gain some things by not insisting on returning to the launch site, since I > imagine that places some restrictions on size and speed. I'm just pointing out that there is more than one way to avoid the "flyback" aspect, if you're willing to abandon traditional "optimal" staging. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein >A better approach might be to return to the launch site by having the first >stage launch essentially straight up. Launch failure and range safety destruct results in debris falling all over the launch site, and possibly onto populated areas. The higher the detonation, the bigger the fallout zone, even Orlando and Dizzy World might be rained on if the wind is right. Not good. Brian >>A better approach might be to return to the launch site by having the >>first [quoted text clipped - 4 lines] > the detonation, the bigger the fallout zone, even Orlando and Dizzy > World might be rained on if the wind is right. Not good. Who said anything about launching from KSC? I'd rather new systems launch from places more like Edwards AFB, where such failures are (or historically were) accepted as standard operating procedure when testing high performance experimental aircraft. It's a hell of a lot easier to land such a vehicle on a huge, dry lakebed than to try to land it on a relatively small concrete runway or landing pad surrounded by swampland. In fact, the first shuttle landings were at Edwards AFB for precisely these sorts of reasons. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein >> Launch failure and range safety destruct results in debris falling all >> over the launch site, >Who said anything about launching from KSC? I'd rather new systems launch >from places more like Edwards AFB, So... to save a little money, you want to uproot the entire U.S. launch infrastructure and rebuild it 3,000 mile away? Brian > So... to save a little money, you want to uproot the entire U.S. > launch infrastructure and rebuild it 3,000 mile away? Not to be nitpicky, but *cough*Vandenberg*cough*. SignatureThis is a siggy | To E-mail, do note | Just because something It's properly formatted | who you mean to reply-to | is possible, doesn't No person, none, care | and it will reach me | mean it can happen >>> Launch failure and range safety destruct results in debris falling all >>> over the launch site, [quoted text clipped - 4 lines] > So... to save a little money, you want to uproot the entire U.S. > launch infrastructure and rebuild it 3,000 mile away? Reusable launch vehicles should not need the same sort of "launch infrastructure" you need for expendables. Furthermore, I wasn't thinking NASA would be doing this sort of work anyway. They're too busy building son of apollo/saturn/shuttle to give a damn about reusability of liquid fueled first stages (SRB's don't count as reusable in my book). Still, if you were to launch from KSC or from Cape Canaveral Air Station, you could have the vehicle fly east just enough for safety, which would require far less than the shuttle's maximum crossrange for a return to launch site landing of the first stage. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein >>>> Launch failure and range safety destruct results in debris falling all >>>> over the launch site, [quoted text clipped - 7 lines] >Reusable launch vehicles should not need the same sort of "launch >infrastructure" you need for expendables. Only if you've invented some kind of magical launch vehicle that doesn't require infrastructure. Whether reuseable or expendable, real launch vehicles requires hangars, maintenance facilities, fueling facilities, personnel support, etc... etc... D. SignatureTouch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL >>Reusable launch vehicles should not need the same sort of "launch >>infrastructure" you need for expendables. [quoted text clipped - 3 lines] > launch vehicles requires hangars, maintenance facilities, fueling > facilities, personnel support, etc... etc... Sure, but they don't necessarily need the *same* sort of launch infrastructure originally put in place for Saturn V. The VAB, crawler/transporters, MLP's, and huge fixed launch structures like the Shuttle pads were all left over from Saturn V. It's just possible that launch infrastructure designed 40 years ago isn't optimized for a high flight rate, reusable, launch vehicle. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein On Mar 18, 10:21 am, "Jeff Findley" <jeff.find...@ugs.nojunk.com> wrote: > >>Reusable launch vehicles should not need the same sort of "launch > >>infrastructure" you need for expendables. [quoted text clipped - 13 lines] > Jeff > -- The launch infrastructure is not just launch complexes, it includes the range and payload processing facilities > The launch infrastructure �is not just launch complexes, it includes > the range and payload processing facilities- Hide quoted text - > > - Show quoted text - hey you better tell sea launch somehow they are muddling thru at the equator with a few ships On Mar 18, 8:52 pm, bob haller safety advocate <hall...@aol.com> wrote: > > The launch infrastructure �is not just launch complexes, it includes > > the range and payload processing facilities- Hide quoted text - [quoted text clipped - 3 lines] > hey you better tell sea launch somehow they are muddling thru at the > equator with a few ships Hey, I am telling you to don't bother to post since you are wrong They aren't launching over land or near the public, which eliminates range safety. The command ship with is the same thing as the range wrt telemetry, but the range can handle more launches There is a large infrastructure in Long Beach for processing the spacecraft On Mar 18, 8:27 pm, charliexmur...@yahoo.com wrote: > On Mar 18, 8:52 pm, bob haller safety advocate <hall...@aol.com> > wrote: [quoted text clipped - 15 lines] > There is a large infrastructure in Long Beach for processing the > spacecraft well that infrastructure is a fraction of what nasa would want to do anything........... its past time to privatize everything about nasa but exploration On Mar 18, 10:01 pm, bob haller safety advocate <hall...@aol.com> wrote: > On Mar 18, 8:27 pm, charliexmur...@yahoo.com wrote: > [quoted text clipped - 20 lines] > well that infrastructure is a fraction of what nasa would want to do > anything.......... Again, stop with the posting since you are wrong., especially with asinine blanket statements NASA doesn't do any of those things listed 1. Range safety is the USAF 2. The Range is USAF 3. There are commercial processing facilities at both coasts, and NASA must use them 4. NASA must use commercial launch services On Mar 19, 6:51 am, charliexmur...@yahoo.com wrote: > On Mar 18, 10:01 pm, bob haller safety advocate <hall...@aol.com> > wrote: [quoted text clipped - 37 lines] > > - Show quoted text - my point is that space launch does things seemingly on the cheap, as compared to the bloated pork of nasa. who tried to design ares as a payoff to existing contractors rather than build a modern affordable safe system > On Mar 18, 8:52 pm, bob haller safety advocate <hall...@aol.com> > wrote: > > hey you better tell sea launch somehow they are muddling thru at the > > equator with a few ships > > Hey, I am telling you to don't bother to post since you are wrong Bob Haller should be in *everyone's* killfile. Please do us all a favor and don't bother replying to his posts. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein Bob Haller should be in *everyone's* killfile. �Please do us all a favor and > don't bother replying to his posts. > > Jeff jeff doent like the truth and note he doesnt discuss the pork piggie thats well on its way to being a pork piggie failure.......... the group supposed to solve the vibration has been disbanded, its head looking for a new job........... typical nasa:( study study study and dont design stuff that affordable design to pay off contractors. congress should investigate how ARES came about to prevent it from happening again......... On Mar 13, 11:46 am, "Jeff Findley" <jeff.find...@ugs.nojunk.com> wrote: > Who said anything about launching from KSC? I'd rather new systems launch > from places more like Edwards AFB, where such failures are (or historically > were) accepted as standard operating procedure when testing high performance > experimental aircraft. Has nothing to do with the locale >Who said anything about launching from KSC? I'd rather new systems launch >from places more like Edwards AFB, where such failures are (or historically >were) accepted as standard operating procedure when testing high performance >experimental aircraft. You're deluding yourself Jeff. The losses were expected, not accepted. Even so, it doesn't matter where you launch from - nobody is going to expect or especially accept the loss of millions of dollars worth of hardware. >It's a hell of a lot easier to land such a vehicle on a huge, dry lakebed >than to try to land it on a relatively small concrete runway or landing pad >surrounded by swampland. Nonsense. If your control system isn't reliable enough to land on a normal runway or landing pad, you shouldn't be flying the vehicle in the first place. This is 2008, not 1948. D. SignatureTouch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL the down path loss of a orbiter falling on downtown chicago or any other heavily populated area is why KSC was built in the first place......... KSC was hardship duty early on a bug infested swamp, with gators added, for excitement. much of KSC was citrus farms, which are still there. but it wasnt a nice place back then, but was chosen for the large ocean dumping ground >>Who said anything about launching from KSC? I'd rather new systems launch >>from places more like Edwards AFB, where such failures are (or [quoted text clipped - 7 lines] > is going to expect or especially accept the loss of millions of > dollars worth of hardware. If we're ever to develop truly reusable launch vehicles, losses will be unexpected, but accepted as part of the initial test program. The shuttle program was very lucky not to lose an orbiter during the Enterprise drop tests and the first "test flights" of Columbia. Actually, the shuttle program has flown so few missions that it never truly got out of the "test flight" stage. The recent failures of, and fix found for, the LH2 fuel cutoff sensors is a good example of this. >>It's a hell of a lot easier to land such a vehicle on a huge, dry lakebed >>than to try to land it on a relatively small concrete runway or landing [quoted text clipped - 4 lines] > normal runway or landing pad, you shouldn't be flying the vehicle in > the first place. This is 2008, not 1948. Stuff happens and it's better to be prepared for it than not. Note how many of the initial shuttle landings were at Edwards AFB, not KSC. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein >>>Who said anything about launching from KSC? I'd rather new systems launch >>>from places more like Edwards AFB, where such failures are (or [quoted text clipped - 8 lines] >If we're ever to develop truly reusable launch vehicles, losses will be >unexpected, but accepted as part of the initial test program. Not if the engineers have done their sums right Jeff. This isn't 1958, its 2008. >>>It's a hell of a lot easier to land such a vehicle on a huge, dry lakebed >>>than to try to land it on a relatively small concrete runway or landing [quoted text clipped - 5 lines] > >Stuff happens and it's better to be prepared for it than not. If your backups can't carry out a normal mission profile, you shouldn't be flying in the first place. You shouldn't even be bending metal. If you lose your primary and backup for a major system - you're likely augering in whether your target is a runway in a swamp or a runway on a dry lake bed. D. SignatureTouch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL >>Stuff happens and it's better to be prepared for it than not. > [quoted text clipped - 5 lines] > augering in whether your target is a runway in a swamp or a runway on > a dry lake bed. Stuff still happens. Remember the Boeing 737 rudder actuator problem that caused more than one 737 to auger in? That really ugly design problem didn't raise its ugly head except in certain circumstances. The actuator was designed such that it did have a backup, but under certain thermal conditions, this backup caused the actuator to fail "hard" to one side. Once everything else was ruled out, it took a heck of a lot of lab testing to finally recreate the circumstances which would cause it to fail. And the above example of a passenger airliner failure is from a class of vehicles that we have orders of magnitude more experience with than reusable spacecraft. Losses are always unexpected, but will have to be accepted if you want to make progress. We don't have enough experience with reusable launch vehicles yet. It's the unknown unknowns that really bite you in the a.s. Jeff SignatureA clever person solves a problem. A wise person avoids it. -- Einstein >>>Stuff happens and it's better to be prepared for it than not. >> [quoted text clipped - 17 lines] >vehicles that we have orders of magnitude more experience with than reusable >spacecraft. And, germane to the topic at hand - they augured in regardless of where they were supposed to land. Or, in other words... so effin' what? Yes, stuff happens. But it isn't germane to the topic at hand. >Losses are always unexpected, but will have to be accepted if >you want to make progress. Done flag waving and marching arm-in-arm into the misty future yet? >We don't have enough experience with reusable launch vehicles yet. It's the >unknown unknowns that really bite you in the a.s. None of which changes my basic point. But repeating recieved dogma always makes for a nice sound bite. D. SignatureTouch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL >A better approach might be to return to the launch site by having the first >stage launch essentially straight up. Sure, the second stage takes a bit of [quoted text clipped - 4 lines] >launching straight up is that this approach works well for varying >inclinations since the first stage always comes down at the launch site. I suspect you'll want some horizontal velocity out of the first stage (either pre or post sep), otherwise you end up with it coming in very hot ('sporty' not temperature). Any reasonable first stage is going to be fairly fluffy, so that might not be a big issue - but horizontal velocity equates also to cross- and down- range capability, which makes targeting and the landing much easier. D. SignatureTouch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL > Also, how likely was it that the copy of Bill Gerstenmaier that jogged > past me on the beach a couple miles south of the port wearing an STS-1 > t-shirt was the original? I saw this post today, at 2:38 pm CDT 3/12. Bill Gerstenmeier walked past my console in the MER at JSC this morning about 9 am. Hence the likelihood, while not zero, is fairly small. Mike Ross > I saw this post today, at 2:38 pm CDT 3/12. Bill Gerstenmeier walked past > my console in the MER at JSC this morning about 9 am. Hence the > likelihood, while not zero, is fairly small. Ask him where he was roughly 5 hours after the launch. :-D SignatureThis is a siggy | To E-mail, do note | Just because something It's properly formatted | who you mean to reply-to | is possible, doesn't No person, none, care | and it will reach me | mean it can happen |
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