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2 of 2 people found the following review helpful:
5.0 out of 5 stars
A Solution to the Launch Problem? Maybe, September 7, 2008
If you want to really blow the doors off space development, read on. This might be it.
Transportation from Earth to orbit, space launch, is extremely expensive ($2K - 20K per kg) and dangerous (a few percent failure rate). This is what makes everything we do in space so ridiculously expensive. The fundamental reason for this difficulty is the extremely high temperatures, large forces, and fast decision making required to ride a tower of flame to orbital velocity (~28,000 km/hr).
Floating to Space by experimentalist John Powell lays out a solution that just might work; at a tiny fraction of the cost of alternatives. The basic idea is to use three types of lighter-than-air ships. The first travels from Earth to about 120,000 feet. Research balloons do this all the time, no problem. The second lives permanently at about 120,000 feet. Research balloons have stayed this high for long periods of time, but permanence requires on-site maintenance and Powell seems to understand more-or-less how to do this. More important, he has demonstrated some of the key capabilities in ground test. The last vehicle is a km-scale, inflatable, hypersonic flying wing that uses electric thrusters to achieve orbital velocity over a period of days. This is the hard part.
I don't know how to figure out if this works, but I intend to learn. It might be easier than many a launcher development we have already achieved. The key is that the atmosphere doesn't end at 100 km, it extends much further although it is very diffuse. The vehicle's enormous size allows aerodynamic forces generated by a diffuse atmosphere to provide lift. This lift allows very slow acceleration into orbit. Slow acceleration allows use of extremely efficient electric propulsion. Deorbit is relatively easy - pitch the vehicle up to expose its enormous cross section to atmospheric forces. This will decelerate the vehicle enough in a diffuse atmosphere that reentry heating is minor. The orbital vehicle then docks with the station at about 120,000 ft. Unlike today's rockets, there are no high temperatures, no enormous forces, and time is measured in hours not milliseconds. This just might be relatively easy to do. Maybe.
Powell's book is written for the lay public. Although he lays out the approach and the known problems, there is not enough detail to make a technical evaluation. The good news is that Powell is very open about his failures as well as his successes. He meticulously describes the dozens of balloon launches JP Aerospace, his company, has attempted with an entertaining description of the many accidents and problems. In addition, there is an entire section of the book devoted to the challenges that must be overcome. To my mind the most difficult and critical is reducing the orbital vehicle's drag -- or perhaps providing more thrust. Current materials, vehicle designs, and engines are insufficient.
America is spending nearly a billion dollars per shuttle flight. Flights after 2010, if funded, will cost two billion dollars apiece. For a fraction of one shuttle launch we could find out if Powell's vision will work. If it does, for far less than NASA's new launcher, we might well drop the cost of launch by a factor or 10 or more. Maybe much more. This would allow space solar power, lunar and martian bases, space settlement, asteroid mining and a thousand other applications to bloom. The wealth, power, and knowledge to be gained are immense.
If Powell is close to right, we need to do this. Now.
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1 of 1 people found the following review helpful:
5.0 out of 5 stars
Boldly going where no one has gone before, August 17, 2008
I loved reading this book.
John Powell shares his dream for safe low cost journeys to space, weaving fact with fiction (his Son grown up traveling to space via airships). This is no idle dream. As JP shows, he and his crew are slowly developing and testing progressively more capable high altitude airships and floating way stations.
Mr. Powell and associates are also very practical planners. They've arranged funding from small corporate adds at the 'edge of space' to huge experimental airships with military sponsorship. They even include free rides for student 'pongsats'...ping pong balls full of experiments from students around the world.
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5.0 out of 5 stars
Flying slowly to space, May 10, 2009
This is a fascinating idea. Powell's very accessible presentation of his idea to use airships to get to orbit is a truly novel idea. If it was just an author's musings it would be fun, but possibly nothing more. But Powell has an aerospace company that is building prototypes on a commercial basis to get his vision realized. So far it seems that the floating stratosphere station is feasible, as is the winged airship to reach it. What is not so clear is can even this part be made operational. But way off the scale is the huge, mile long, winged airship/plane than slowly ascends from the station to orbit. I have no idea whether this is feasible, and Powell acknowledges that this is unknown territory with only a few signposts and needs a lot of research. But as I blogged ( http://mymeemz.blogspot.com/ ), even if only the floating station was feasible, this would in itself be a worthwhile platform for science, commerce and tourism. It doesn't have to be all or nothing, and as Powell demonstrates, each piece of puzzle can be commercialized to make it pay its way.
This book isn't perfect. It could have done with a good editor to get rid of spelling and grammatical errors. In 2 places, the US airship Macon is misnamed Macron, not a good detail to get wrong for a book devoted to airship designs as a way to get to space. But these are nit picks. Overall this book is a worthwhile read, and like the space elevator concept, should inspire a lot of thought and work to realize. The floating station idea could even use an elevator or tether for experiments and transport.
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