Micro-Space >> Ultralight Manned Spaceflight

[rpspeck]

I should have noted that sunlight will make both the orbiter and the lander easily visible - to a camera with an adequate sunshield + surface light shield (and possible Earth Light shield).  With such glare reducers, the orbiter's path can easily be tracked against the dark, starry "sky".

Imaging can document these motions before and during the rendezvous effort.  We have operational versions of the required systems and they play an important part in our Mars expedition navigation.  

However, I still consider the RF link system a little easier to implement and automate.

Active light sources (both lasers and LEDs) have the advantage over passive reflection of "self identification" for high confidence and also allow "time of flight" ranging.

[rpspeck]

MARS expedition progress:

An update on Micro-Space “Deep Space” life support breadboards (11/16/07):

Our “Zero G Centrifuge” continues to spin smoothly at 14 times the necessary speed.  It has now logged 810 days of nonstop operation at this speed.  Operation for the full 1000 days needed for a low energy Mars mission is very likely – particularly slowed to design speed (1/14 of that used in the “accelerated life test”).  

As already pointed out, even if reliable operation for 1000 days were unlikely, this lightweight unit could easily be backed up with spares.  At 500 grams for each assembly (but processing and recycling more than 2000 grams a day of highly contaminated water) several could be carried as spares or rigged for online backup operation.  This unit is full sized for recycling the biowaste from one space traveler.


We have a second life test running to evaluate our preferred gas transfer membrane in a MEA (Monoethanolamine) CO2 absorber system.  This chemistry is routinely used to scrub the CO2 in nuclear submarines and offers high efficiency and long life.  Our configuration will use considerably less energy in the recycling process than that used in these subs.  While decomposition of the MEA occurs in the process – producing a finite life – it occurs slowly and will require less than 1 kg of MEA to absorb the 1000 kg of CO2 produced by an astronaut on a 1000 day mission.  

No operational problems have appeared to make our low estimated weights for long duration life support equipment achievable, nor the affordable human missions that this allows.  Admittedly, more certain answers could be obtained if funding were available to accelerate the transition from engineering breadboards to operational prototypes.  But, in spite of the reluctance of astronauts and sponsors to step forth for this historic work, progress continues.    

[rpspeck]

“INTENTIONS”

Micro-Space has a short, but growing list of committed customers for space adventures.  Some of our offered space flight options have been reviewed in these pages.

If our philosophical ramblings have lead to doubt about Micro-Space intentions, I want to reiterate them here:

Micro-Space will be flying adventurers into near and interplanetary space at “affordable” prices. That certainly means LEO at a small fraction of the “pre inflation” Russian price, and deep space adventures at comparable ($10-$20 Million) prices.  

These are “extreme adventure travel” opportunities – a category climbing Mount Everest fits into - not safe, and not easy.  “Tourists” are not invited: adventurers are.

Our posts have recently focused on Lunar and Mars adventurers which start with commercial launch services.  These will certainly be accomplished, with their ultralight systems making unexpectedly small – and low cost – launch vehicles adequate for even historic interplanetary missions.

On the other hand, the small number of launch companies – with or without SpaceX success – guarantees a near monopolistic business environment for the foreseeable future. It is unlikely that any launch provider will welcome innovative uses of their vehicle – such as ultralight manned flights - which compete with their more expensive human flight offerings.  Therefore I reiterate Micro-Space’s intention to provide independent ultralight flights from Earth to LEO.

The clustered “Small Dumb Boosters” we use have low development and production costs, and can equally be bundled to lift moderate sized expeditions above LEO, or minimal mass human systems from Earth to orbit.  

A list of historic “Mantras” – replayed reflexively by old space hands – need to be discarded to understand the options Micro-Space offers.  One we energetically countered in this forum was the blind assertion that “the second stage of a launch vehicle always costs more than the first stage”.  It is very valuable for new space engineers to understand that this counterintuitive proposition MIGHT be true in a specific case.  But the Jupiter C and related Juno 1 (which launched the first American satellite) certainly flag the “Always” claim as the lie it is.

Very experienced aerospace engineers have claimed that “Big Dumb Boosters” – simple and low cost “Pressure Fed” liquid rocket systems – can be much more cost effective then the elegant machinery flown today.  These radicals have been regularly shouted down and denied funding by the “experts”.  The rationale has always been that this tempting assertion is “unproven”.  It takes a while to learn that the second stages of the very successful “Delta II”, as well as that of the Falcon 1, use only pressure fed motors and achieve the large majority of orbital velocity.  All controlled lunar and interplanetary rockets – like the Apollo LEM - use such simple pressure fed motors because of their high reliability and low development cost.

Micro-Space could well be the first company to use such well proven, reliable and low cost propulsion to lift humans into orbit.

Many discussions in this forum emphasize the “complexity” of combining or clustering rocket motors and propulsion modules.  It is certainly true that this is not trivial, and real engineering effort is involved, but the extensive offerings and frequent flights of launch vehicles augmented by customized clusters of “strap-on” boosters mark this too as false.

A fixation on “Reusable” launch vehicles as “the only way to reduce costs” is also common. Similar arguments can and have been made about “upgradeable” computers or cell phones, but we have moved into an era where the most affordable “high technology” products are disposable!  Cell phones, game machines and computers now pile up in landfills. Those who have lived for more than a few decades also know that automobiles and airplanes are “used up” and are disposable.  

It has long been true on frontiers that transportation costs so far exceed production costs that “recycling” is impractical.  On the order of a million people traveled the Oregon and California Trails without using vehicles capable of multiple round trips. (That had to wait for 1869 and the transcontinental railroad.)  But the pioneers did optimize their vehicles and their loads.  

Optimized “disposable” launch vehicles – like ours - will dominate cost effective space flight for many years to come and will be used by those who don’t want to wait.

Seize the Dream ™

[Lampyridae]

rpspeck - 4/11/2007  4:23 AM
Our normal Lunar plan would be to use two of the pictured vehicles per traveler.  One would land with 300 pounds of fuel, instead of a human occupant.  When safe arrival of this "return fuel" was confirmed by radio, the traveler would descend on a second unit.  The extra fuel, sent first, would be transfered into the main tanks of either vehicle for use to return to lunar orbit.  Spare vehicles and fuel could be sent down to provide an even higher redundancy level.

I follow your logic. For me, getting a pilot's license looked way too expensive until I thought about parasailing. It's not as if I need a plane to go anywhere, I just want to muck around in the air.

I would just love it if you guys beat NASA to the moon. I would be tickled pink, I really would.

Instead of transferring fuel, how about this: simply have a second valve for the tanks. For landing, you run on the centre tanks (where Sally stands). The returning astronaut just disconnects the almost-empty centre tanks and tosses them, then climbs into the now vacant space. The side tanks are full and the astro-nut is go for lift-off.

[jimvela]

Lampyridae - 13/12/2007  9:38 PM
I would just love it if you guys beat NASA to the moon. I would be tickled pink, I really would.

Sorry, they're already 38 years late.

Beat them back to the moon, well maybe...  

I'd love to see small innovative teams pull these kind of things off.  

But, I'm skeptical- and though I'll root for them, I don't consider it likely that they'll succeed.

No one would be more happy than me if I'm wrong about that. :-).

[Lampyridae]

Putting a human being on the moon is not a trivial thing. I've seen some of the other attempts that Micro Space is talking about, and they don't have a snowball's. Micro Space has IMHO the best shot. The "orbital skydiver" routine, if it pans out, would be an interesting low-cost access to space.

Balsa wood heatshield, eh? Stranger things have happened. It was only 70 or so years into heavier than air flight that we got stuff like microlights.

[edkyle99]

jimvela - 14/12/2007  11:04 AM

Lampyridae - 13/12/2007  9:38 PM
I would just love it if you guys beat NASA to the moon. I would be tickled pink, I really would.

Sorry, they're already 38 years late.

Beat them back to the moon, well maybe...  

Too late.  NASA has already been "back" to the moon, in 1998 with Lunar Prospector.  

http://lunar.arc.nasa.gov/

 - Ed Kyle

[rpspeck]

Lampyridae - 17/12/2007  6:41 AM

Putting a human being on the moon is not a trivial thing. I've seen some of the other attempts that Micro Space is talking about, and they don't have a snowball's. Micro Space has IMHO the best shot. The "orbital skydiver" routine, if it pans out, would be an interesting low-cost access to space.

Balsa wood heatshield, eh? Stranger things have happened. It was only 70 or so years into heavier than air flight that we got stuff like microlights.

I mentioned BALSA Wood specifically because it was one of the heat shield materials studied in an Arc-Jet tunnel with other lightweight reentry heat shield materials (published by Huy K. Tran, January, 1994 in NASA Technical Memorandum 108798).

While not impressive in performance, it was serviceable.  At the studied heat loads, it offered 1/2 to 1/4 the heat absorption capability (Btu/lb mass) factor of the (unobtainable) Avcoat used for Apollo.    More modern PICA shield materials (in NASA TM 110440) run from 2x better than Balsa at modest heat loads to 10x that performance level at high heat loads (which Balsa wouldn't tolerate).  

Balsa is obtainable and adequate and serves as a good baseline for a heat shield mass.  The fact that a number of Chinese craft have reentered successfully with OAK heat shields is similarly promising.  

Endgrain Balsa is also an outstanding alternative to "Foam Core" for composite structures.  Skinned with Graphite cloth and a high temperature epoxy/phenolic resin, it promises to make a heat tolerant, load bearing substrate for the ablative layer (balsa or PICA).  This approach promises a reentry system below my targeted mass, easily produced with standard methods and modest cost.

New materials often aren't worth their added cost and applications complexity.  

[rpspeck]

The First Few

Many readers probably suspect that I do not have the resources to accomplish all that I have mapped out.  You and I both have a similar suspicion about most other entrepreneurial launch companies, although they have various planned “solutions”.  I confess that I do not have the resources to complete the work I have outlined.  But similarly, I did not have, at the outset, the resources to accomplish the liquid fuel rocket flights or near hover guided launches I/we have already accomplished.  

This has been a 17 year “Faith Walk” depending on God’s provision and wisdom at each step.  Unexpected money became available for the work while, simultaneously, simpler and lower cost solutions were recognized to make the funds sufficient. No textbook outlined the rocket designs we have succeeded in flying, and none outlines the low cost, manned spaceflight systems we have extensively discussed.  I am confident that progress in these efforts will continue and that God will continue to provide the resources, insights and partners required for these efforts to succeed.

This “funding” history is recognized in our displays, listing “The Lord Jesus Christ” as our primary sponsor.  (Online photos include photo 10 of 22 at:
http://www.pythom.com/news.php?id=15240 ).

At present ALL of the technologies necessary for lightweight expeditions to Mars and our Moon have been identified and verified by Micro-Space in operational prototypes. The production of customized flight hardware and validation by tests in space remains.

From the practical standpoint, I was chief engineer when a company I founded sold millions of dollars worth of automated HUD and HMD display test equipment to various DOD components, and received commendations for outstanding contractor performance for some of that work. Previously, I guided the development of remote sensing tools sold to NASA and several universities, production monitoring equipment for semiconductor processing and other high tech processes and robotic vision systems sold to the navy and DOD contractors. Prior work included sales of standard and customized test sets to Kodak, Polaroid, Leitz, Hassleblad and other world class photo equipment manufacturers. These quantified the performance of auto focus, exposure control, electromechanical and photometric systems in cameras.  Other projects actually included production of transistors, integrated circuits, vacuum tubes, thin film coatings and hybrid circuits in both experimental and production applications.  Thus I can project success with these new technologies and applications with confidence.    

As few as six to seven partners with a passion for personal involvement in space adventures, and capable of matching the level of personal investment I have made, can see their dreams of personal space flight fulfilled and make a mark on its history.    

This small group, currently locked out of space by enormous costs and inflexible selection rules for the few who can go, has the power to complete the funding – personally and through sponsorship – of  the affordable systems I have outlined and redefine the economic standard for all subsequent human spaceflight. As customers they form the “protected niche” prescribed by Clayton Christensen (in “The Innovator’s Dilemma”) necessary for a “disruptive technology” like this to succeed.  

The “Option” plan we have developed may allow those who elect not to personally participate in a selected adventure - when the time comes to ramp up investment by actually contracting for flight hardware and third party launch services – to recoup a multiple of their investment by transferring their option to another individual.  In any case, it is a strong inducement for partners to lock in the flight opportunity which matches their dreams early with an appropriate financial commitment.

Near term Micro-Space objectives include full operation of both our lightest competition “Lunar Lander” and the nearly simultaneous CHTS (Crusader Human Transport System).  The later will qualify in the “NG Lunar Lander” level 2 competition and also fly in human “Space Diving” modes.  With Fuel tanks sized for human Moon landings, Earth launch can provide flights approaching 50 km altitude.  With the larger Mars sized tanks, flights above 100 km are feasible.  The lightest system can serve for the Google Lunar X Prize competition, which, in our plan, will also be used to qualify a number of our human use systems in space.

There is no question that exciting projects can attract substantial sponsorship money and, although raising this form of funds is one of my weaknesses, modest support of this kind has already been received.  More generous funding will depend on passionate individuals, with exciting personal plans, who are willing to share their enthusiasm with the public.  A significant level of early investment in specific missions will be necessary to sustain the equipment development.  A personal Moon landing could involve less investment that a Soyuz ride, but real faith and seed money are necessary to move these projects to the point where YOU can talk sponsors into fronting the money to put YOU onto the Moon or Mars.  


Richard P. Speck,  Micro-Space, Inc. ,  December 19, 2007  

[A_M_Swallow]

rpspeck - 19/12/2007  9:21 PM
{snip}
Near term Micro-Space objectives include full operation of both our lightest competition “Lunar Lander” and the nearly simultaneous CHTS (Crusader Human Transport System).  The later will qualify in the “NG Lunar Lander” level 2 competition and also fly in human “Space Diving” modes.  With Fuel tanks sized for human Moon landings, Earth launch can provide flights approaching 50 km altitude.  With the larger Mars sized tanks, flights above 100 km are feasible.  The lightest system can serve for the Google Lunar X Prize competition, which, in our plan, will also be used to qualify a number of our human use systems in space.

As I understand this Micro-Space manufactures:
1. a 50 km sounding rocket (cargo version of the Crusader Human Transport System)
2. a 100 km sounding rocket
3. plans to make the sounding rockets usable by people by "Sky Diving" the pilot back to Earth
4. a cargo lunar lander with ascend stage.

Plans include:
a) a space suit rated for several days
b) a space suit rated for several weeks
c) equipment that allows an astronaut to move in space
d) a personnel manned lunar lander called the CHTS (Crusader Human Transport System)
e) a cargo variant of the CHTS
f) a set of two/three landers that allow a person to land on the moon and return to low lunar orbit
g) controls that permit the CHTS to climb mountains on the moon and cross uneven ground
h) a Mars variant of the Lunar landers
i) a balsa wood heat shield
j) some sort of "capsule" to go with the heat shield and space suits

[Lampyridae]

Perhaps you should consider solar thermal propulsion for your Mars mission:

http://sbir.gsfc.nasa.gov/SBIR/abstracts/02/sttr/phase2/STTR-02-2-020031.html
http://www.jstage.jst.go.jp/article/tjsass/46/153/46_180/_article

Isp on the order of 400-800s seems reasonable, provided the technology can be developed. For a non-government, privately funded mission, I'd strongly recommend this. LH2 could power your outbound stage (say 800s), and ammonia could be your propellant for return (400s). Even a 3m diameter concentrator could get you 10N of thrust in LEO.

Let's have a look at the mass budget:

Mirror + engine: 200kg
Inflatable hab: 1000kg      
2 Crew: 200kg            
Food, air water for 500 days for 2: 3000kg            
Personal effects. medical supplies: 100kg            
4 advanced spacesuits: 400kg         
Recycling / hygiene: 300kg            
Avionics: 100kg            
Attitude control: 100kg            
Solar power: 100kg            
Mars MOOSE: 500kg            
Earth MOOSE: 500kg            
Ammonia tankage: 500 kg         
Hydrogen tankage: 1000kg            
Mars capture heatshield: 1000kg         
Outbound dry mass: 9000kg   
Return dry mass: 4800kg
LH2 Propellant: Earth C3 + TMI = 4kps = 12000kg
Ammonia Propellant: Mars C3 + TEI = 2.5kps = 3900kg

There is of course a requirement for another launch carrying hab and supplies for the surface stay, plus ascent propellant. I assumed a heatshield for Mars orbital capture. But the final craft ways in (according to my highly uneducated guess) at 25 tonnes, which could be launched a Falcon 9 Heavy. The cargo could probably fly on a Falcon 9.

[sandrot]

Solar thermal and aerocapture are yet to be proven technologies. If they were to be used for a manned mission that manned mission would be far in the future.

[meiza]

One pass aerocapture is hard.
All Mars probes nowadays use multi-pass aerocapture as a significant lowerer of orbit insertion propellant demands.

[Lampyridae]

Well, the MicroSpace proposal is going to have to have a whole host of unproven technologies to succeed. A couple of years ago, inflatable habs were unproven, and now a couple are in orbit. I considered solar sails before solar thermal, and realised that although the potential capabilities were greater, solar sails were a much harder technology to develop.

I don't think that a solar thermal engine is a hard technology to develop, especially compared to say, a first stage engine with turbopumps. It's reasonably small and quite simple, especially compared to ion/plasma drives. Ground-based models have been vacuum tested.

Single-pass aerocapture is a bit dodgy, I agree. If you're doing everything on the cheap, a finicky aerocapture is probably not a good idea. At any rate, given the mass of the heatshield, it might be preferable to just use propellant as normal for orbital capture - especially if the heatshield is made of higher-mass, lower quality stuff. I assumed leaving the hab in a highly elliptical orbit and then expending extra propellant from the surface to get there (which may or may not work out cheaper than bringing the hab to LMO).

[rpspeck]

It appears to me that aerocapture to a high, elliptical orbit is quite well proven.  Only a few hundred meters per second delta V are required.  Since this is a survival issue, there are several ways that descent fuel could be tapped to back up that effort.  This would reduce or eliminate the landing effort, but save the crew.  We did a detailed design of a "Star/Planet Optical Tracker" (adapting optical gaging hardware we have in production) for periapse prediction of the planetary intercept.   Less that one km of error is definitely achievable (12% of drag and delta V uncertainty relative to a "known" atmosphere).  If Martian atmospheric density still remains uncertain (which seems unlikely), we outlined a "pilot probe", monitored optically and by coherent radio link, to verify aerobraking while there was still time for periapse adjustments.  

All my scenarios show that preserving most of the Mars escape energy has a big payoff.  Bear in mind that I am thinking about first forays, with minimum mass.  The stay on the Mars surface could be short, with limited exploration.  The longer stay could be in orbit, using already proven systems.  

I am well aware that "camping" at high mountaineering altitudes on Earth presented unexpected problems when it was first tried!  A commitment to live for over an Earth year in a unique environment may not be a good idea.  I am not particularly excited about giving up 70% or more of solar cell output (due to nighttime and illumination angle), on the surface, and adding dust and wind problems.  

While I understand the argument for "One Big Expedition", such efforts are seldom fundable (because of the massive uncertainties) and rarely do well if funded.  New exploration almost always starts with by risking only a small group with simplified goals.  In this, and most other cases, the unnecessary equipment avoided by knowing which problems are real and which are only imagined outweighs the cost of the first expedition.

Once the possibility of using a small, gutsy group to check out Mars at low cost sinks in, serious ($$$) support for the "Big Expedition" as a first effort will evaporate.  

The Solar Thermal Engine is a good idea.  I would appreciate more information on it (using Ammonia or Hydrazine fuel and what refractories in the heat transfer "chamber" ?).  It should of course resemble the "Resistojet" in many ways. It does drop the "gravity well" benefit of burning your fuel (fairly quickly) when deep in a planetary gravitational field.

[hop]

rpspeck - 24/12/2007  11:24 AM

It appears to me that aerocapture to a high, elliptical orbit is quite well proven.  Only a few hundred meters per second delta V are required.  

Err, what actual missions have used areocapture ? Areobraking has been used, but this is used to circularize an initial elliptical orbit that was established by conventional propulsion. As currently practiced it is also a slow process requiring many passes.  

Aerocapture has been studied, but AFAIK has never been used in a flown mission.

The variability of mars atmosphere would add significant complexity/risk to the mission (current aerobraking missions tune each pass get get the desired dV and heat load.)

Also, I'm not sure where  you get a few hundred m/s dV. If I'm not mistaken, the dV for MROs orbit insertion was something closer 1000 m/s (for a 45000x420km orbit), and then a similar amount was provided by aerobraking to get into the desired orbit (over a period of ~500 orbits). Obviously this can be tuned somewhat depending on your requirements, but minimizing the required orbit insertion dV would have been a major priority for MRO... even with aerobraking, a large portion of spacecraft mass was taken up by orbit insertion propellant.

[tnphysics]

Aerocapture requires a heat shield. This is why it has not been used much before.

Why not NTR?

[kkattula2]

IIRC, aerocapture has been used on 9 manned missions, about 35 to 40 years ago.  Of course the desired orbit was much, much lower. 0 x 0 nm, I believe.

[hop]

kkattula2 - 26/12/2007  8:24 PM

IIRC, aerocapture has been used on 9 manned missions, about 35 to 40 years ago.  Of course the desired orbit was much, much lower. 0 x 0 nm, I believe.

You might have a semantic argument there but the practical relevance to the topic at hand seems pretty small. A direct entry is a different problem than using the atmosphere to get into orbit, and has been used not just for quite a few other things on both earth and mars.

The zond skip re-entries might be a bit closer, but even that's a stretch.

[dtbaird]

There have been no missions to demonstrate aerocapture - neither at Earth nor Mars.  There was a new millennium aerocapture mission proposed in response to the last AO, but the selection of a mission was canceled.  Aerocapture is much more difficult than aerobraking because the spacecraft has to endure much higher heating loads and g-loads while using onboard guidance to fly a pre-determined density profile.  Then, upon exiting the atmosphere the spacecraft must shed the heat shield, orient properly, fire thrusters to establish an orbit, all the while having to contend with pointing solar arrays at the sun to recharge the batteries.  In aerobraking, there is no onboard guidance to fly a density profile (this is pre-analyzed on the ground), there is not nearly as much heating and g-loading, and there is no immediate concern about the spacecraft being lost by re-entering the atmosphere because each pass is designed such that the spacecraft can survive 24 hours in the event of lost communication.  The spacecraft does, however, have to worry about re-orienting its solar arrays after each drag pass.

By the way, the U.S. has never demonstrated skip entry either, although the guidance algorithm was included onboard the Apollo missions to be used in the event of a contingency.  The Russians tried it, and it is my understanding that they succeeded on 1 of 4 attempts.  Any information on this would be appreciated.