Which is more effective, disposable capsules or reusable spaceplanes?

[FADEC]

There had been really few missions in which the shuttle returned empty, and in all such cases, in which the Shuttle returned payloads, it returned much more payload than what existing or proposed capsules can return. Even for smaller experiments hosted in the Mid-deck, the capability to return the experiments completely was very important - because it permits you to do much more complex research including research on the experiment hardware after the mission.

Payload is not just the payload bay - but even then it was more often returning cargo, than returning empty.

More precisely I meant returning cargo collected from earth orbit. If we talk about science equipment the Shuttle indeed returned a lot. But returning experiments (mid-deck) in a big winged vehicle for about 1 billion USD (per launch) seems a little expensive. Build a bigger capsule and you might return more experiments home than the Apollo guys did dream of.

 

[Urwumpe]

More precisely I meant returning cargo collected from earth orbit. If we talk about science equipment the Shuttle indeed returned a lot. But returning experiments (mid-deck) in a big winged vehicle for about 1 billion USD (per launch) seems a little expensive. Build a bigger capsule and you might return more experiments home than the Apollo guys did dream of.

The problem is, you can't build infinitely large capsules. There are limits, especially at the parachute end.

Also, the Shuttle was only able to return payloads from below 600 km altitude, which are not many and which then also need to be designed for the payload bay.

 

[FADEC]

One situation when the shuttle did bring a lot of payload home was the MLPMs. The station crew put a lot of equipment and gear in those for the return home.

That's what the Shuttle was made for. Low earth orbit transportation and building a space station. But if we want too see manned things happening on asteroids, the Moon and Mars in future, we won't go by costly spaceplanes.

And since we can build a space station without any Shuttle involved (also faster and cheaper), the age of such kinds of spaceplanes certainly is over. I am sure we will see a revival in the future, when new technology enables an effective propulsion to build something like Concorde but for higher speeds and altitudes to cross the Atlantic ocean in 30 minutes or so. But the age of winged space transportation systems certainly is over. To what we might see in future, I consider the Shuttle an old steam engine in a museum

---------- Post added at 01:11 PM ---------- Previous post was at 01:08 PM ----------

The problem is, you can't build infinitely large capsules. There are limits, especially at the parachute end.

Also, the Shuttle was only able to return payloads from below 600 km altitude, which are not many and which then also need to be designed for the payload bay.

Yes. But the Apollo capsule for example, was not the end of the flagpole.

 

[Urwumpe]

And since we can build a space station without any Shuttle involved (also faster and cheaper), the age of such kinds of spaceplanes certainly is over. I am sure we will see a revival in the future, when new technology enables an effective propulsion to build something like Concorde but for higher speeds and altitudes to cross the Atlantic ocean in 30 minutes or so. But the age of winged space transportation systems certainly is over. To what we might see in future, I consider the Shuttle an old steam engine in a museum

That is exactly the attitude and argumentation, that makes we want to shout unprintable words and go wild. Because it is not only nonsensical culture pessimism pretending to be engineering knowledge, but also a complete loser attitude.

I don't know where you have spent the last 31 years, but according to the Space Shuttle, the technology exists already - we just prefer to cut ourself and cry about the world being so unfair, instead of doing what we already can.

And I don't see yet that any successor of the Space Shuttle operated by NASA will become cheaper.

---------- Post added at 03:22 PM ---------- Previous post was at 03:20 PM ----------

Yes. But the Apollo capsule for example, was not the end of the flagpole.

Sure, but also not comparable to a winged vehicle. The current record for military cargo parachutes is 40000 lb or 20 tons. And such parachutes don't need to operate at high Mach numbers (maximal slightly supersonic for drogue chutes, but still much more than the Mach 0.3 of a cargo plane), like those for capsules.

 

[N_Molson]

I'd say that capsules are best for transporting crews, and that unmanned winged bodies would be nice to haul the big space station parts, and serve as mobile workshops. Buran did a perfect unmanned landing during its only flight, so we know it's possible.

 

[Tacolev]

Buran also demonstrated the flexibility of having your spaceplane launch with an HLV rather than serve as a 50 ton payload-fairing.

This is very important politically if you look at every NASA DRM since apollo: They all assume a big politicall-impossible HLV. If you've already sold policy-makers on the system and it can transition seamlessly between throwing up the space-plane for on-orbit assembly, station downmass and crew transportation versus being an HLV with 100 tons of throw-weight you are fairly insulated against budget-cuts and schedule slips for the development of any new capability.

 

[Aviator]

It always seemed wastefull to me to spend all that fuel carrying up wings and landing gear into orbit when the wings are only going to be used in the last 15 minutes and the wheels only during the landing roll.

A spacecraft will never be as cost effective or efficient as it could be with wings and wheels, there surely has to be a better option.

 

[Urwumpe]

It always seemed wastefull to me to spend all that fuel carrying up wings and landing gear into orbit when the wings are only going to be used in the last 15 minutes and the wheels only during the landing roll.

A spacecraft will never be as cost effective or efficient as it could be with wings and wheels, there surely has to be a better option.

Same applies to heat shield and parachute. Honestly, if you think not landing at all is better, you can sure design something without return option and without landing systems.

Wings and landing gear are actually mass-wise pretty effective, the penalty for the wing structure and landing gear is on the average around 2-3% higher than for heat shield and parachutes with ocean landing. The development costs for a spaceplane are just higher, since the aerodynamics, control systems and structural dynamics are more complex.

If it is only about costs, a simple capsule will always beat a space plane for less than 100 missions. You just have to remember that you also get less for less money.

 

[Jarvitä]

SpaceX has a pretty creative solution to that inefficiency - using the same thrusters for LES, RCS and powered landing.

 

[N_Molson]

SpaceX has a pretty creative solution to that inefficiency - using the same thrusters for LES, RCS and powered landing.

Mmmhyeah... Let's see if the Dragon can reach the ISS before considering more advanced options...

Still, Soyuz has proven to be the most "resilient" spacecraft concept. And it sure wasn't overfunded during the 80's - 2010's (it seems that things are getting a little better in Russia on that side). It has a sort of powered landing, for the last centimeters of the descent. :lol:

 

[Delta glider]

If in like 200 years time the XR-2 gets inventedP )then it will be cheaper than capsules.:lol:

 

[richfororbit]

STS was good for the time. I was thinking about Commander Younge's mission into orbit since it is about thirty four years now.

How society was at the time, they were two privledge white men orbiting the Earth, just two in a two deck crew section. What a ride.

I even thought a day or so go, the idea of a woman as commander on that mission or black Astronauts etc was still a few years away.

It was a great machine, as Mr younge said in April 2006 of his flight, there wasn't and still isn't a rocket that could take a shuttle to the Moon.

I think realistically, capsules are the future until as Delta glider has stated, that not until something revolutionary is invented, it's really only two ways for personnel based missions.

 

[orbitingpluto]

I wouldn't think to participate in thread necromancy like this, but I really got to ask:

STS was good for the time. I was thinking about Commander Younge's mission into orbit since it is about thirty four years now.

How society was at the time, they were two privledge white men orbiting the Earth, just two in a two deck crew section. What a ride.

I even thought a day or so go, the idea of a woman as commander on that mission or black Astronauts etc was still a few years away.

First off, how can you get John Young's name wrong? Twice?:rant:

The second thing is where are you going with this 'white male privilege' stuff? [ame="http://en.wikipedia.org/wiki/NASA_Astronaut_Group_8"]Astronaut Group 8[/ame], who were recruited in 1978, already were showing the way towards the day when NASA would fly people who are something other than white males. It's true that none of them could have completed training soon enough to fly STS-1, but that has less to do with gender inequality or racism than it has to do with realities of becoming a trained astronaut and then having the right skills for a particular mission.

For the record, the first mission with Group 8 members was STS-7 in June of '83, and Sally Ride became the first American women in space on that mission; and STS-8 in August of the same year had Guion Bluford aboard. So from 1978 forward, NASA had people in training who were not white males, and just two years after the first flight of the Shuttle the first female and black astronaut had missions and flew.

While not evidence of a absence of gender or racial inequality at NASA, Group 8 at the very least were a highly visible sign that times were changing, and the doors to being an astronaut where considerably more open.

Especially since, in a job requirements sense, starting with Group 8 NASA wouldn't require everyone to certified as a pilot anymore. The mission specialist position allowed people to become astronauts without also taking a year or so to go to pilot school, an extra hurdle that NASA foisted on 'scientist-astronauts' like those of [ame="http://en.wikipedia.org/wiki/NASA_Astronaut_Group_4"]Group 4[/ame] and [ame="http://en.wikipedia.org/wiki/NASA_Astronaut_Group_6"]Group 6[/ame]. It could be argued that the requirement to be a pilot, especially a test pilot or military test pilot, more than anything else, is what caused NASA's astronauts to be as white and male as they were up to Group 8.

So, with all this in mind, where the heck are you getting that society wasn't ready for black or female astronauts? Or that it was 'years away', which in my mind, 'years' implies more than just two, more like 5 years at least.

 

[PhantomCruiser]

I think Shuttle is still a great machine, just retired - but not obsolete. Winged craft can find a purpose, still have purpose. Take a look at the latest unmanned dream chaser. Current capsule design doesn't have nearly as much down-mass, and I don't think anything on anyone's drawing board could math the Shuttles down-mass capability.

 

[Urwumpe]

I think Shuttle is still a great machine, just retired - but not obsolete. Winged craft can find a purpose, still have purpose. Take a look at the latest unmanned dream chaser. Current capsule design doesn't have nearly as much down-mass, and I don't think anything on anyone's drawing board could math the Shuttles down-mass capability.

Also... nobody is caring about the payload bay. I am pretty sure, at least the astronauts will miss it.

 

[N_Molson]

Oh, not the capsule vs spaceplane thing again

 

[richfororbit]

I wouldn't think to participate in thread necromancy like this, but I really got to ask:




First off, how can you get John Young's name wrong? Twice?:rant:

The second thing is where are you going with this 'white male privilege' stuff? Astronaut Group 8, who were recruited in 1978, already were showing the way towards the day when NASA would fly people who are something other than white males. It's true that none of them could have completed training soon enough to fly STS-1, but that has less to do with gender inequality or racism than it has to do with realities of becoming a trained astronaut and then having the right skills for a particular mission.

For the record, the first mission with Group 8 members was STS-7 in June of '83, and Sally Ride became the first American women in space on that mission; and STS-8 in August of the same year had Guion Bluford aboard. So from 1978 forward, NASA had people in training who were not white males, and just two years after the first flight of the Shuttle the first female and black astronaut had missions and flew.

While not evidence of a absence of gender or racial inequality at NASA, Group 8 at the very least were a highly visible sign that times were changing, and the doors to being an astronaut where considerably more open.

Especially since, in a job requirements sense, starting with Group 8 NASA wouldn't require everyone to certified as a pilot anymore. The mission specialist position allowed people to become astronauts without also taking a year or so to go to pilot school, an extra hurdle that NASA foisted on 'scientist-astronauts' like those of Group 4 and Group 6. It could be argued that the requirement to be a pilot, especially a test pilot or military test pilot, more than anything else, is what caused NASA's astronauts to be as white and male as they were up to Group 8.

So, with all this in mind, where the heck are you getting that society wasn't ready for black or female astronauts? Or that it was 'years away', which in my mind, 'years' implies more than just two, more like 5 years at least.

It is the truth, and that is okay, considering the history.

As a black guy from New York State put it to me last year when I was on a mandatory volunteering program, due to me being on a benefit claimanent. He said bluntly, space flight was for rich white folks.

And I couldn't disagree with him. He said he remembered seeing the Challenger explosion on television. He must of been over forty years old.

I was the youngest person sent to a gardening place on a housing estate. What a way for government to force the unemployed to volunteer while living on pennies.

Anyway, the point being it was years away. The Astronaut corps has been like that.

Reflecting on the time, Mr Young was a veteran yes, and Mr Crippen was on his first mission. But they still had that minority privledge to do something that nobody else could at that time in that moment. There thousands more nuclear weapons at that time, smoking everywhere. It was just horrendous!

And those early black and women of colour were on the first for training.

 

[PhantomCruiser]

- - - Putting on moderator hat for a moment - - -

The topic at hand is essentially winged vehicles v capsule; merits of each.

If anyone wants to discuss the scocioeconomic merits of the astronaut corp (past and present), please start a new topic (preferably in the basement).

 

[Linguofreak]

The same model put Saturn V at 1/6.

I find it very difficult to believe that the LOCV risk for Saturn V was 1/6. I can believe that the risk of failing to reach orbit was that high (though I don't believe any Saturn V ever did fail to reach orbit, and more than 6 were launched), but Apollo, unlike the Shuttle, had viable abort options from the ground straight up to orbit. I'd say that the most optimistic LOCV risk quotes for the Shuttle (1/250) were probably on the pessimistic end for Apollo/Saturn, and 1/1000 may well have been achievable for Apollo as flown. (I say "as flown" because the capsule design used for Apollo 1 had an empirical LOCV rate of 1/0, but that was unrelated to launcher failure).

 

[Urwumpe]

I find it very difficult to believe that the LOCV risk for Saturn V was 1/6.

The statistic of 1/6 LOCV for Apollo is real - but it was estimated at the earliest design stages of Apollo, before even the final configuration was decided.

The real LOCV was likely 1:15- 1:20 for Apollo.