Griffin Favors Shuttle SRB for Launching CEV

[gladiator1332]

I wonder if Lockheed used a parasail, much like that was to be used on X-38, if they could get some sort of a runway landing. Probably not though, seems the only way would be to give it some more lift. <br /><br />Personally I think they should just use the X-38 for their concept and just pick up where they left out. Don't they already have part of it built anyway? They did drop tests with it as well. Why start frmo scratch when you have a perfectly good lifting body sitting around.

 

[spacefire]

the X-38 was a testbed for a Crew Return vehicle. Of course, it could be scaled up- check out HL-20 and HL-42 at www.astronautix.com<br /><br />they have the same basic shape but the HL-20 is a CRV while the HL-42 is used to send people to orbit and bring them back.<br /><br />the X38 shape is the most efficient lifting body config ever developed (originally called the SDV when it was first invented), and has been investigated extensively in most flight regimes it would encounter. I would think the CEV would make use of all this data . Northrop's design for the OSP had this shape, so maybe that's why Lockheed isn't using it for their CEV as it appears in their sketches. <br />Somehow, in big companies, it's like individual inteligences cance eachother and you have an entity equivalent with a ****** doing random things. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[gladiator1332]

How much, if anything would have to be changed on the X-38 to enable it to fly lunar missions? I'm assuming it was able to stay in space rather long, if it was going to be attached to the station as a CRV. <br />And I don't even think they would have to scale it up that much, as right now, the crew for the CEV will be around 3 or 4. They would just have to add a mission module and propulsion module. <br /><br />It just doesn't make sense to take out a clean sheet of paper for a new design, when you already have a vehicle that hes been tested over many years, sitting around.

 

[gladiator1332]

Here is the only thing that would hold it back:<br /><br />"Future Plans<br /><br />Although the design could one day be modified for other uses such as a crew transport vehicle, the X-38 would strictly be used as a CRV in its current design. It is baselined with only enough life support supplies to last about nine hours flying free of the space station in orbit."

 

[yree]

bump

 

[scottb50]

The main problem with the SRB remains the separate Segment design, chosen because of the convenience for shipping the Segments from Utah.<br /><br />If the SRB was a single piece Carbonfiber tube and the propellant was poured into non-structural Segments, the segments inserted into the tubes it would be a lot safer. <div class="Discussion_UserSignature"> </div>

 

[steve82]

The segmented design probably wouldn't be that much of an issue as a centerline thrust CEV carrier. For one thing, there would probably be less stress on the Field Joint without all of those bending moments you get during the twang when you're launching a shuttle. Even if the O-Ring fails, it's a fairly robust design-on 51L that SRB kept chugging along all through the breakup even while it was leaking out the side. That sort of event would be survivable with a CEV on top/launch escape system. I'm thinking back and the last time I recall a big solid just flat out exploding was that Titan 34D that experienced a burn-through out at Vandenberg in 1986. With some system upgrades, like the new Helium driven APU, and a fiber-optic burn through sensor like Rutan's rocket has, a shuttle-derived SRB might make a pretty good vehicle. They could make the filament-wound ones onsite in Brevard County and provide some steady work for the area too. Alas, given the short time frame everyone is talking about, I'm not sure NASA will be able to build the simulator for it in the next 8 years using their current business practices, let alone the real thing.

 

[scottb50]

The SRB's started out too complex, because of logistics, and the Challenger fixes added another layer on top of the first. From what I understand the reflight capability of the segments is not all that great anyway.<br /><br />Whether a hybrid engine like SS-1 would be better than a straight solid would probably figure into the time line. It just makes more sense having a solid case enclosing the segmented fuel modules. Not that much of a shift from the current configuration, use the existing nozzle technolgy, just change the containment system from o-rings and flanges to a single piece composite tube. <div class="Discussion_UserSignature"> </div>

 

[steve82]

There will definitely be a lot of recertification. Just because you're building it out of "man-rated" components that are flying in formation does not make it an integrated "man-rated" system. Everything that's been certified to ride on the shuttle will have to be recertified to ride on the standalone SRB, which more than likely will have a completely different vibro-acoustic environment if nothing else. I'm guessing a rougher ride. All of those ISS ORU's that had to be individually certified first for carry on a shuttle and then for carry on a Progress will again have to be certified for an SRB. What are they going to use for flight software? Are they going to try to use a subset of the PASS software in AP101's? There probably aren't even enough shuttle Ap101 computers in existence to support a new vehicle unless they start the production line back up now. It took a couple years just to modify the PASS to accomodate the drag chute and now they want to modify enough software to steer and guide an entire new vehicle? Oh, they want to start from scratch? Good luck, we'll be very old men when it flies if that is the case.<br /><br />I still think it's probably a good idea, though.

 

[steve82]

"I forgot to add and new software. "<br /><br />Therefore, with new avionics and software, it will definitely have to be recertified. How many years have they been tinkering MEDS?<br /><br />

 

[spacefire]

can the SRB+CEV be air-launched? <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[john_316]

Isn't that what Scale Composites was looking for with the T/Space version?<br /><br />Would conceive its possible but I guess depends on the weight issue of the actual CEV design correct?<br /><br /><br />Safety note but not to add more weight too the CEV if it is a lifting body design but what if......<br /><br />CEV could have a built in Roll Cage like NASCAR accept with a self contained cabin attached to the rest of the CEV components. I had mentioned this a year or so ago on the OSP threads. <br /><br />So that if CEV launch is compromised and rocket blasts CEV clear that if CEV parachutes fail the cabin can detach and parachute deploy thus a second backup for the CEV crew.<br /><br />

 

[john_316]

Shuttle_Guy time to pick your brain here....<br /><br /><br />So with certification of the SRB/CEV design we could expect to have launch almost on demand?<br /><br />We could have say bi-weekly or at least monthly launch feasibly with the SRB launches correct?<br /><br />I ask that because if we use existing SRBs and upgrade to new systems and such that the cost still should be way lower than an EELV correct? Even STS?<br /><br />I ask that because it would seem to me that some hidden cost for vehicles will go away and thus allow the procurement of more CEV vehicles, thus allowing a dedacated CEV processing facility while the SDHLV will have a seperate processing facility or the VAB. <br /><br />Could SRB/CEV be moved by rail that way as well and 2 pads configured to fly it? I am not up on how many pads can be refurbished at the cape but ones that are not currently used could benefit from this new vehicle.<br />

 

[tap_sa]

<font color="yellow">"can the SRB+CEV be air-launched?"</font><br /><br />Estimated weight of the Stick is ~700 tonnes, that is more than maximum take-off weight of world's largest airplane Antonov An-225 (600t).

 

[strandedonearth]

"Estimated weight of the Stick is ~700 tonnes"<br /><br />*Looks at Mr. Rutan...* "Well, Burt? Can you?"<br /><br />Aside from the fact that the Stick would probably need to recerted against the loads it would see during an air-launch...

 

[spacefire]

assuming you can airlaunch the SRB+CEV, what kind of payload increase would you get if ignition occured at 30,000ft? <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[yree]

bump

 

[yree]

http://www.safesimplesoon.com/assets/documents/derivatives-video.asx

 

[no_way]

I guess if youre ATK Thiokol its a wise investment to spend a few bucks on continuing propaganda in favor of shuttle-derived everything, to keep the billions flowing into your pockets for many years to come.

 

[vt_hokie]

Reviving the wings vs lifting body vs capsule debate, check out this concept for a CEV with apparently retractable wings:<br /><br />http://www.andrews-space.com/en/news/CEV_landing.htm<br /><br />Seems to add unnecessary weight and complexity to me - what's the advantage over fixed wings such as an X-37 type of configuration?<br /><br />Also, is Russia looking at a runway landing variant for the "Kliper"? Check out the winged version shown on this site:<br /><br />http://www.russianspaceweb.com/kliper.html<br /><br />

 

[lunatio_gordin]

well, with retractable wings, you don't have the loads like on the space shuttle. Also, it's less area you have to protect with heat shields. But i don't think that's enough weight to counter the retraction mechanism.

 

[spacefire]

why is everybody so convinced a pure lifing body can't land on a runway?<br />Think HL-10,X24,M2F2...and with fly by wire and computer augmented stability a similar craft wuld be fairly easy to fly, especially if you increase the size to keep the same loading. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[j05h]

>why is everybody so convinced a pure lifing body can't land <br /> />on a runway?<br /> />Think HL-10,X24,M2F2...and with fly by wire and computer <br /> />augmented stability a similar craft wuld be fairly easy to fly, <br /> />especially if you increase the size to keep the same loading.<br /><br />My concern with the concept of a horizontal landing lifting body or delta wing is that it is unneccessarily complex, especially for an crew vehicle. You want a vehicle that is simple, robust and survivable. Follow the KISS principle, not preconcieved notions. This points to a water landing, semi-reusable capsule, in my opinion. Any vehicle that requires active control during descent is begging for trouble.<br /><br />Josh<br /> <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[no_way]

<blockquote><font class="small">In reply to:</font><hr /><p>Follow the KISS principle, not preconcieved notions. This points to a water landing, semi-reusable capsule, in my opinion.<p><hr /></p></p></blockquote><br />I'd say capsule with steerable parafoil, skid landing is pretty simple too with todays technology. It was tested on X-38 and parafoils in general have been around long enough. This would avoid salt water and buoyancy issues, with basically no extra added weight and slight increase in complexity.

 

[spacefire]

josh, I think a lifting body is fairly simple. true, it has control surfaces, but other than that everything goes inside the thick body, no wings to worry about.<br />think of it as a capsule with fins and landing gear. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>