Micro-Space >> Ultralight Manned Spaceflight

[Robotbeat]

umm... what about a launch escape system, seats, life support, etc?  How can you fit all of that down to 500kg?

The idea is to trade risk for cost.

That means throwing out the launch escape system, for instance.

Lots of people are pretty skeptical of this sort of approach.

[tigerade]

umm... what about a launch escape system, seats, life support, etc?  How can you fit all of that down to 500kg?

The idea is to trade risk for cost.

That means throwing out the launch escape system, for instance.

Lots of people are pretty skeptical of this sort of approach.

For good reason.  I'd love to travel to space, but I'd appreciate even more coming back in one piece.

[kkattula]

umm... what about a launch escape system, seats, life support, etc?  How can you fit all of that down to 500kg?

You do what Dragon is doing, dual-purpose RCS and retro fuel as abort fuel.  3 x 1500kgf engines will give a 9g abort. One at 50% throttle will provide a gentle 1.5g retro burn, with triple redundancy. And they should only mass about 20 kg each.

Seats can be very light, t-space came up with a reversible sytem that only weighed a few kg.

Life support for a few hours needn't weigh much, think what's in a space suit to support an astronaut for 10+ hours.

The Mercury capsule was, IIRC, around 1300 kg. Batteries, electronics, structural materials, etc, are all much better now. Plus it was over-engineered because it was a completely unknown evironment. Reduce the mass & volume of all those, and there is a more than corresponding reduction in required propellant, tankage, parachutes, heat shield, etc.

[93143]

...do you know what a sounding rocket is?  The Black Brant series are not orbital launchers.  Even if the payload to orbit for a given configuration can be shown to be positive, it won't be half a tonne or anywhere near it.

[Lars_J]

Yep, if you want to put 500kg in LEO, you'll need a Falcon 1-sized LV.

I seem to recall that there was some discussion here at the time about how one would build a 1 person capsule for the Falcon 1.

[SpaceGeek123]

I quite like this method of sending people into Space. It really could reduce the cost per person to orbit significantly. The Russian Shitl rocket for example has a launch cost of $200,000 and can send 430 kg to Orbit. Even if a full fledge capsule with only one person in it was launched that would still lead to routine almost airline operations.

[douglas100]

You fancy being shot into orbit from beneath the Barents Sea? Good luck!

[douglas100]

Even if a full fledge capsule with only one person in it was launched that would still lead to routine almost airline operations.

No it wouldn't. Soyuz launches are "routine." They are emphatically not airline operations. About the only thing launch vehicles and airliners have in common is that they both fly.

I think the Mercury spacecraft was close to the minimum mass that could safely support one human in orbit for its time. Using modern materials and systems you could possibly get the mass under 1000kg for the same capability, but I doubt it could be made as low as 400kg and support a single person safely.

[SpaceGeek123]

Even if a full fledge capsule with only one person in it was launched that would still lead to routine almost airline operations.

No it wouldn't. Soyuz launches are "routine." They are emphatically not airline operations. About the only thing launch vehicles and airliners have in common is that they both fly.

I think the Mercury spacecraft was close to the minimum mass that could safely support one human in orbit for its time. Using modern materials and systems you could possibly get the mass under 1000kg for the same capability, but I doubt it could be made as low as 400kg and support a single person safely.

Ok Airline maturity was a bit of an exaggeration but no by much. There could be a demand of at-least 1000 people per year at that price. Thats 3 per day or once every 8 hours. The Umaskiy Caspule design by the Soviet Union was exactly in the range I was talking about.
http://www.astronautix.com/craft/umapsule.htm

[Jim]

A big exaggeration.  Also, you have no data to support your claim of demand.

[Comga]

umm... what about a launch escape system, seats, life support, etc?  How can you fit all of that down to 500kg?

The idea is to trade risk for cost.

That means throwing out the launch escape system, for instance.

Lots of people are pretty skeptical of this sort of approach.

For good reason.  I'd love to travel to space, but I'd appreciate even more coming back in one piece.

You didn't listen to the video.  He envisioned missions in the style of Shakleton. 

  "MEN WANTED FOR HAZARDOUS JOURNEY. SMALL WAGES,
   BITTER COLD, LONG MONTHS OF COMPLETE DARKNESS,
   CONSTANT DANGER, SAFE RETURN DOUBTFUL. HONOR AND
   RECOGNITION IN CASE OF SUCCESS." 

Safe return doubtful, not Rescue ship standing by.
You wouldn't have gone.  I probably wouldn't have gone.  Some did.  Others would.
Young and Crippen rode STS-1, which hindsight says had a 10% probablility of LOC.  Steely eyed rocket men.

[SpaceGeek123]

A big exaggeration.  Also, you have no data to support your claim of demand.

 
http://www.friends-partners.org/partners/mwade/craft/geleraft.htm
Actually it could be much less than 400 kg It could even be 80 kg per person.

http://www.futron.com/upload/wysiwyg/Resources/Whitepapers/Space_Transportation_Costs_Trends_0902.pdf
80 kg times $465/kg =$37 200 per seat

http://www.nss.org/tourism/settlement.htm

[Jim]

1.  http://www.friends-partners.org/partners/mwade/craft/geleraft.htm
Actually it could be much less than 400 kg It could even be 80 kg per person.

http://www.futron.com/upload/wysiwyg/Resources/Whitepapers/Space_Transportation_Costs_Trends_0902.pdf
80 kg times $465/kg =$37 200 per seat

http://www.nss.org/tourism/settlement.htm

Wrong again.  That is an bailout system and not a spacecraft capable of launch and orbiting.  And it was never developed, for many good reasons.
80kg is no where close to a legitimate number. 

Also, your document is 10 years outdated and not applicable to today

same with your reference.

Seriously, find some relevant and current data.  And have you designed or built any or are you just going to post links meaningless links

[SpaceGeek123]

Its a spacecraft capable of reentry. It could easily be modified for people to  orbit. Even if it were 430 kg instead of 80 thats still enough for one person on the shtil rocket. Thats $200,000 for a one person to orbit.

[Jim]

Its a spacecraft capable of reentry. It could easily be modified for people to  orbit. Even if it were 430 kg instead of 80 thats still enough for one person on the shtil rocket. Thats $200,000 for a one person to orbit.

No, it is not a spacecraft, it is a foam cocoon.  It can't handle the rigors of launch.  You don't even know what you are talking about.

And no one is going to ride a shtil, so your point and cost numbers are meaningless. 

Also, the cost numbers are for existing vehicles, not one modified for capsule with a launch pad to support manned operations.   

Bring some reality to the discussion.

Rockets are not Legos.

[mmeijeri]

Rockets are not Legos.

Not questioning what you said and not questioning you, but aren't some rockets less unlike Legos than others? Specifically, weren't Titan III and Delta 2 supposed to be very modular?

[Jim]

Rockets are not Legos.

Not questioning what you said and not questioning you, but aren't some rockets less unlike Legos than others? Specifically, weren't Titan III and Delta 2 supposed to be very modular?

They were designed that way

[mmeijeri]

They were designed that way

Is that part of the reason they were relatively expensive?

[Jim]

They were designed that way

Is that part of the reason they were relatively expensive?

yes, because they weren't clean sheet designs.

[SpaceGeek123]

Its a spacecraft capable of reentry. It could easily be modified for people to  orbit. Even if it were 430 kg instead of 80 thats still enough for one person on the shtil rocket. Thats $200,000 for a one person to orbit.

No, it is not a spacecraft, it is a foam cocoon.  It can't handle the rigors of launch.  You don't even know what you are talking about.

And no one is going to ride a shtil, so your point and cost numbers are meaningless. 

Also, the cost numbers are for existing vehicles, not one modified for capsule with a launch pad to support manned operations.   

Bring some reality to the discussion.

Rockets are not Legos.

If it can stand the high temperatures, high speed, and high Gs of reentry explain why it couldn't take all this during launch. Also the Umanskiy Capsule was developed so that it could bring people up as well as down if you actually read the article.  I see no reason why the shtil rocket
couldn't be man-rated just like any other rocket. But lets assume that the Shtil will never be man rated. This could still very well work. The Black Brant XII costs $600,000 per launch. It has a payload of 410 kg. Even if only a One person capsule can be taken this is still 83 times less than he $50 million per seat on the Soyuz. The current reliability is 98%. This was roughly the reliability of the Space Shuttle so it should be acceptable for the Manned Missions.