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[yale]

Apollo-like capsule may replace shuttle

CAPE CANAVERAL, Florida (Reuters) --NASA may replace its troubled fleet of space shuttles with a new generation of Apollo-type space capsules, a top space agency official said.

"Certainly we have considerable amount of experience flying with capsules," Dr. John Rogacki, director of NASA's space transportation directorate, told Reuters on Wednesday. "One might say on the capsule side it could be that that design experience may lead to a capsule being available sooner than a winged vehicle."

Unlike shuttles that land like airplanes, capsules splash down in the ocean and must be recovered by ships.

The resurrection of space capsules, which last launched three decades ago, is gaining favor among astronauts, space agency officials and congressional staffers after the shuttle Columbia disaster that killed seven astronauts on February 1.

The 13 members of the Columbia Accident Investigation Board were unanimous in urging NASA to replace the aging shuttles as soon as possible by using existing technology and materials.

NASA said on Tuesday that the next space shuttle flight, designed to test repairs that might have saved Columbia, would not make a March launch target and might not fly until midsummer.

The space agency has spent billions of dollars since the mid-1990s trying unsuccessfully to design a new winged spacecraft, begging the question of whether a winged plane could be delivered by 2008 under a now accelerated timetable.

"Boy, I really don't want to speculate on that because I don't want to inadvertently or unintentionally signal to our contractors that I think it is likely or it is not likely," Rogacki said.

Waiting for decades
Corin Segal, an aerospace scientist at the University of Florida, picked by NASA to design new systems, has estimated that development of the technology to produce a truly safe, winged reusable spacecraft could take 15 to 20 years.

Detailed requirements for what has been called an orbital space plane were issued by NASA this week to three contractor teams who will propose designs and compete for the work.

For now, NASA is careful to avoid publicly expressing any opinion on what shape the new craft should take, and to stress that there are pros and cons to winged and capsule designs.

But NASA spokesman Bob Jacobs said there was no requirement that the craft be plane-like despite its name.

"We haven't spelled out that it has to glide back to Earth and land like a plane. That's not a requirement," Jacobs said.

The capsule design gained momentum in March from a study headed by astronaut John Young, who has flown in both capsules and shuttles.

Young, as well as Michael Kostelnick, head of NASA's human space flight program, cite the versatility of the capsule, which can move beyond low Earth orbit to the moon or beyond.

Rogacki said the orbital space plane requirements did not demand the vehicle be capable of deep space travel but that NASA will be looking at its ability to support missions beyond the International Space Station.

"There is a great potential for using the orbital space plane system as a basis for future exploration vehicles," Rogacki said.

The thermal tiles and wing panels used on the shuttle today could not withstand the heat and stress of trans-lunar re-entries.

[LunarOrbit]

I'm liking this idea more and more all the time. Ideally I would like to see a fully reusable space plane, but I think capsules have their benefits.

For example, we could use them for the ISS for now and then if we decide to return to the Moon all we would have to do is use a more powerful rocket and add a lunar module... that would be much easier to do than if we use a space plane.

[Skyjim]

Absolutely agree that this is likely to  be the way things go - but the article is incorrect on several points, ignoring decades of Soyuz ops ("capsules splash down in the ocean"  and "last launched three decades ago..").  I understand that the writer is referring to Apollo capsules, but it's sloppy wordsmithing! I've found many of Reuters' articles showing this sort of slapdash quality.  

I think the if OSP goes the capsule route, it will need to be routinely recovered on the ground - the  expenses of maintaining recovery fleets would be prohibitive.

I just want to see them maximize the available volume of the basic reentry vehicle - use the Apollo ballistic shape, but enlarged as much as possible within the constraints of the baseline EELV heavy payload capability.  That means 5 meters - just under 16 feet, five inches as a working outside diameter.  That compares to the 12 foot, 10 inch base diameter of the Apollo CM - plenty of volume for a 7 person lifeboat (following the general idea of the Skylab rescue CM seating or 4 crew plus light cargo in the transfer vehicle variant.

The capsule approach is different enough from the various shuttle replacement schemes that it will be a visible departure from the more recent past - bound to be a more palatable option for Congress.  

Let's build 'em - I'm ready to start tomorrow! The first Delta IV Heavy is in integration right now for a maiden flight next year:

http://www.aviationnow.com/avnow/search/autosuggest.jsp?docid=142152&url=http%3A%2F%2Fwww.aviationnow.com%2Favnow%2Fnews%2Fchannel_awst_story.jsp%3Fview%3Dstory%26id%3Dnews%2F09083top.xml
 

We have a long head start on the development on one of the near-term booster options.    Getting the IV Heavy human-rated shouldn't be an excessively lengthy process - it is a very conservative design, a tad heavy to improve producibility.  The RS-68 is built like a tank compared to the SSME, and is a far simpler design.  It will not only be highly reliable and cost-effective, it has thrust growth potential.    The Atlas V Heavy will lag a couple of years, but will eventually be available as well.    

Like Kel says, once in operation, variants could go other places like the Moon or Lagrange points by adding transfer stages and more consumables to the basic "service module" likely to be developed for the basic crew transfer vehicle.   Let your mind go, and imagine a Trans-hab type module docked to the nose of a long-duration version. Service mission to the Webb telescope,  anyone?

[Retrospector]

I join in saying "Yay! Yay!" It would be really great to see NASA get something up and running quickly. There was a New York Times article in the last few days about the idea of inspecting the shuttle from the ISS and accommodating "refugees" within the station in case of severe damage. It was pointed out that even with this option it was not likely to be possible to repair damage on the scale of that to Columbia, not in orbit.

As for the planned Webb telescope, I've been wondering all along if NASA was really going to launch it to the Lagrange point and then leave it inaccessible for servicing by astronauts.

[payloadcontroller]

Meantime, let me tell you what will happen if they pursue this route.

We wind up going, effectively, backwards, and create an Apollo-like capsule for use shuttling to and from Station.

We go to Congress for funding to finish/accelerate Space Plane.

Congress takes a look and says, "Why do you need a Space Plane? You have a perfectly workable capsule. You don't need anything else," and zeroes the SP budget.

We wind up stuck in the 60's.

[LunarOrbit]

Jim,

Do you think it would be possible for capsules to land in the Canadian prairies, or is that too far north? We have a lot of open area, so if a capsule is a little off course it would be less likely to hit something.


Kel

[LunarOrbit]

I think if NASA returned to what they were doing in the 1960's they'd be doing pretty good.  

[Skyjim]

I believe that's truly the intention - and so wonder how "serviceable" the Webb telescope design is.  I have a problem  with that - sensor updates have so enhanced HST over a relatively brief service life that I hope there is some provision for replacement of the Webb's sensor suite.  However, there is a slight cost in mass and  dollars in providing service access - so I do not know if that effort is being made.  

[yale]

Capsules for the intermediate term, then the space elevator at ~20 years out, then the solar system becomes our New Ocean.

[Skyjim]

PLC, I have to tell you, I'm fine with a capsule - just because it isn't winged doesn't necessarily make it primitive.  

 The Apollo shape had a high enough L/D to limit reentry gees to shuttle levels, and there is no reason you can't recover on land if you design for it.  Use a parafoil and you've got the ability to put the thing onto a prepared surface at KSC - certainly our trajectory control should be able to drop a capsule into an energy box above KSC or other sites.  Reusability will have to be studied, but I believe that partial reuse isn't impossible as a design goal - dropping the heat shield is pretty good strategy for a land recovery anyway, cutting your terminal descent rate.  Ablators are well understood and we have enough lift to make the mass acceptable. Maybe you replace skin and heat shield/impact bags after each flight, and cycle avionics/RCS/ECS modules through a diagnostic line if it makes sense on life-cycle costs - but we can do this, and it will go into  service sooner, and I believe it will be a great deal cheaper to develop and operate than a winged fully reusable vehicle.  

The most crucial item is cost - we are looking at a massive federal budget deficit and I don't believe a winged system is going to make it through appropriations.   It's most likely going to have a longer R&D cycle, and will require more complex crew escape systems.  The capsule may look old, but the relative simplicity is going to appeal to bean-counters (Note that I said "relative").

If it gets crews up and down safely, and does it for, say, 200-250 million per flight at the front end of the program, why would this be bad?  Other than large payload recovery, what could you not do with a modern capsule and appropriate modules on-orbit for specific missions?

Jim

[Skyjim]

Kel, yeah, I think you could put it on the prairies.  But I think they will shoot for enough accuracy to bring them back to KSC if possible.  The prairies would be a possible contingency area for the lifeboat scenario, I think.

I'm assuming that there will be an effort to  make the capsules at least partially reusable, with a turnaround line at KSC.

And roger that on the 60s not being a bad time.  Suborbital to Tranquility base in a bit over eight years was pretty damned good...

Jim  

[ottawan]

PLC,

I find it difficult to disagree with you, but I feel I have to agree with Jim & Kel on this one.

I don't believe capsules are "stuck in the 60's" at all.

As a lifeboat for the ISS, they would be exceptionally useful and would also alleviate the need to launch manned crew on a Space Shuttle that could operate unmanned to carry cargo.

Webb servicing, Lagrange missions and a return to the moon would be in the grasp of NASA before an OSP was develped.

Let's go somewhere!

[LunarOrbit]

I agree that returning to capsules seems like a step backwards, and PLC is probably right about how difficult it will be to get funding for a future space plane if capsules are doing the job. But I think we should get away from the space shuttles ASAP, and the best way to do it (in my opinion) is to use capsules. And I think capsules would be more versatile.

I still hope that the HL-42 gets built someday though. It just looks so cool!  


Kel

[yale]

[spacecat27]

Ah- the Ragallo Wing!  They had problems getting the struts to inflate dependably- but if Geminii could have afforded an additional 8 months to a year of R&D it probably would have been perfected and used.
Though it never landed a manned spacecraft- it gave birth to hang-gliding!

Just happened to be reading about this in the book "Arrows To The Moon".