About ASCE; About Civil Engineering; Donate Now; My ASCE; Shop ASCE. ASCE Join Now. Knowledge & L... more About ASCE; About Civil Engineering; Donate Now; My ASCE; Shop ASCE. ASCE Join Now. Knowledge & Learning: Books & Journals; CE Body of Knowledge; Certification; Codes & Standards; Conferences; Continuing Education; ...
A new concept, the magnetic sail, or "Magsail", is proposed which propels spacecraft by using the... more A new concept, the magnetic sail, or "Magsail", is proposed which propels spacecraft by using the magnetic field generated by a loop of superconducting cable to deflect interplanetary or interstellar plasmas winds. A description is given of the computer code used to model the performance of such a device and results of a series of investigations are presented. It is found that a Magsail sailing on the solar wind at a radius of one astronautical unit (A.U.) can attain accelerations on the order of 0.01 m/s 2 , much greater than that available from a conventional solar lightsail. When used as a brake for an interstellar spacecraft, the Magsail can reduce spacecraft velocity by a factor of e every five years. A systems performance code was used to analyze the utility of the Magsail when used in conjunction with either fusion rocket or laser lightsail accelerated interstellar spacecraft. It is found that the Magsail can reduce flight times by forty to fifty years and propellant requirements by thirty percent for fusion rocket propelled ten lightyear missions. The Magsail also provides an efficient method for decelerating laser lightsail propelled missions that are otherwise simply impossible.
This paper steps back and looks at the fundamental economics of people working (and playing) in s... more This paper steps back and looks at the fundamental economics of people working (and playing) in space, and shows scenarios that should result in successful colonies on the moon. The basic premise is the ever increasing cost of industrial metals necessary to generate renewable energy for a growing world population, and the relative abundance of those same metals on the near side of the moon. There is a crossover point, relatively soon, where it is cheaper and more environmentally friendly to mine the moon instead of the increasingly poor ores remaining on earth. At that point government and industry can form a partnership much like The Railroad Act of 1862 to incentivize construction of the transportation infrastructure and lunar mining equipment. The economics say the initial mining equipment will be tele-operated from earth, but over time the requirement for human maintenance and repair seems inescapable. We foresee a government presence on the moon almost from the start of the pro...
This paper presents a Lunar Transportation System (LTS) based on existing technology and liberal ... more This paper presents a Lunar Transportation System (LTS) based on existing technology and liberal use of existing or planned national and international space infrastructure. The objective of the studies described herein was to define a LTS capable of delivering and servicing a manned lunar outpost shortly after the turn of the century. Alternative approaches examined used derivatives of elements from the planned National Launch System or existing international assets to reduce development and launch costs. This study incorporates many design features determined by contracted NASA efforts to reduce nonrecurring and recurring costs for a LTS.
This program led to considerable analytical and experimental ef fort that provided tantalizing, b... more This program led to considerable analytical and experimental ef fort that provided tantalizing, but inconclusive compression results. This paper discusses our proposed follow -on effort. This follow -on effort would provide more analytical detail while exploring the benefit of a smaller fission package and higher yield fraction. The yield fraction (estimated at 10% of the fissionable material from MCNP results) could be increased with a deuterium -tritium fusion boost. We propose to investigate how this approach would improve the system by increasing yield with a small er package and allow for a greater amount of thrust for a given quantity of fissionable material. We will investigate how the magnetic bottle will change under these conditions as well. Finally, we will discuss how this may affect the Z -drive mechanism.
This paper summarizes a commercial Asteroid Mining Architecture synthesized by the Senior Space D... more This paper summarizes a commercial Asteroid Mining Architecture synthesized by the Senior Space Design Class at the University of Washington in Winter/Spring Quarters of 2013. The main author was the instructor for that class. These results use design-to-cost development methods and focused infrastructure advancements to identify and characterize a workable space industrialization architecture including space transportation elements, asteroid exploration and mining equipment, and the earth orbit infrastructure needed to make it all work. Cost analysis predicts that for an initial investment in time and money equivalent to that for the US North Slope Oil Field, the yearly world supply of Platinum Group Metals could be increased by 50%, roughly 1500 t of LOX/LH2 propellant/year would be available in LEO, and very low cost solar panels could be assembled at GEO using asteroidal materials. The investment also would have a discounted net present value return on investment of 22% over twe...
Suborbital Freight, sometimes called Fast Freight, is delivery of high priority packages over int... more Suborbital Freight, sometimes called Fast Freight, is delivery of high priority packages over intercontinental distances in periods of approximately one hour. The vehicles required are usually rocket-powered and have total ideal velocities of around 7.5 km/second. Analysis of this market indicates that there are niches where commercial operations are possible and might even be profitable using today’s state-of-the-art technologies. The key requirements to capture this market are low nonrecurring costs, quick turnaround (<9 hours), and high reliability (0.999). This draft is a report on work in progress. The Fast Freight study will be completed before the STAIF-97 conference and results will be presented at that time.
A comparison of TSTO and SSTO space launch systems is made considering the investment decisions t... more A comparison of TSTO and SSTO space launch systems is made considering the investment decisions to be made for such systems. This comparison will be made using conceptual designs for such systems based upon Boeing current space launch studies. The comparison will include market investment considerations as well as cost and operability concerns.
Interstellar transportation over periods shorter than the human lifetime requires speeds in the r... more Interstellar transportation over periods shorter than the human lifetime requires speeds in the range of 0.2–0.3c. These speeds are not attainable using rockets, even with advanced fusion engines. Anti-matter engines are theoretically possible but current physical limitations would have to be suspended to get the mass densities required. Interstellar ramjets have not proven practicable, so this leaves beamed momentum propulsion as the remaining candidate. This paper reviews the state of beamed-momentum in-space propulsion and presents a point design system suitable for human exploration of nearby stars using today's physics and resources known to exist in the solar system. The total beam energy requirement for an interstellar probe mission is roughly 10 20 J , which would require the complete fissioning of one thousand tons of uranium assuming 35 percent power plant efficiency. This is roughly equivalent to a recurring cost per flight of 3.0 billion dollars in reactor grade enri...
About ASCE; About Civil Engineering; Donate Now; My ASCE; Shop ASCE. ASCE Join Now. Knowledge & L... more About ASCE; About Civil Engineering; Donate Now; My ASCE; Shop ASCE. ASCE Join Now. Knowledge & Learning: Books & Journals; CE Body of Knowledge; Certification; Codes & Standards; Conferences; Continuing Education; ...
A new concept, the magnetic sail, or "Magsail", is proposed which propels spacecraft by using the... more A new concept, the magnetic sail, or "Magsail", is proposed which propels spacecraft by using the magnetic field generated by a loop of superconducting cable to deflect interplanetary or interstellar plasmas winds. A description is given of the computer code used to model the performance of such a device and results of a series of investigations are presented. It is found that a Magsail sailing on the solar wind at a radius of one astronautical unit (A.U.) can attain accelerations on the order of 0.01 m/s 2 , much greater than that available from a conventional solar lightsail. When used as a brake for an interstellar spacecraft, the Magsail can reduce spacecraft velocity by a factor of e every five years. A systems performance code was used to analyze the utility of the Magsail when used in conjunction with either fusion rocket or laser lightsail accelerated interstellar spacecraft. It is found that the Magsail can reduce flight times by forty to fifty years and propellant requirements by thirty percent for fusion rocket propelled ten lightyear missions. The Magsail also provides an efficient method for decelerating laser lightsail propelled missions that are otherwise simply impossible.
This paper steps back and looks at the fundamental economics of people working (and playing) in s... more This paper steps back and looks at the fundamental economics of people working (and playing) in space, and shows scenarios that should result in successful colonies on the moon. The basic premise is the ever increasing cost of industrial metals necessary to generate renewable energy for a growing world population, and the relative abundance of those same metals on the near side of the moon. There is a crossover point, relatively soon, where it is cheaper and more environmentally friendly to mine the moon instead of the increasingly poor ores remaining on earth. At that point government and industry can form a partnership much like The Railroad Act of 1862 to incentivize construction of the transportation infrastructure and lunar mining equipment. The economics say the initial mining equipment will be tele-operated from earth, but over time the requirement for human maintenance and repair seems inescapable. We foresee a government presence on the moon almost from the start of the pro...
This paper presents a Lunar Transportation System (LTS) based on existing technology and liberal ... more This paper presents a Lunar Transportation System (LTS) based on existing technology and liberal use of existing or planned national and international space infrastructure. The objective of the studies described herein was to define a LTS capable of delivering and servicing a manned lunar outpost shortly after the turn of the century. Alternative approaches examined used derivatives of elements from the planned National Launch System or existing international assets to reduce development and launch costs. This study incorporates many design features determined by contracted NASA efforts to reduce nonrecurring and recurring costs for a LTS.
This program led to considerable analytical and experimental ef fort that provided tantalizing, b... more This program led to considerable analytical and experimental ef fort that provided tantalizing, but inconclusive compression results. This paper discusses our proposed follow -on effort. This follow -on effort would provide more analytical detail while exploring the benefit of a smaller fission package and higher yield fraction. The yield fraction (estimated at 10% of the fissionable material from MCNP results) could be increased with a deuterium -tritium fusion boost. We propose to investigate how this approach would improve the system by increasing yield with a small er package and allow for a greater amount of thrust for a given quantity of fissionable material. We will investigate how the magnetic bottle will change under these conditions as well. Finally, we will discuss how this may affect the Z -drive mechanism.
This paper summarizes a commercial Asteroid Mining Architecture synthesized by the Senior Space D... more This paper summarizes a commercial Asteroid Mining Architecture synthesized by the Senior Space Design Class at the University of Washington in Winter/Spring Quarters of 2013. The main author was the instructor for that class. These results use design-to-cost development methods and focused infrastructure advancements to identify and characterize a workable space industrialization architecture including space transportation elements, asteroid exploration and mining equipment, and the earth orbit infrastructure needed to make it all work. Cost analysis predicts that for an initial investment in time and money equivalent to that for the US North Slope Oil Field, the yearly world supply of Platinum Group Metals could be increased by 50%, roughly 1500 t of LOX/LH2 propellant/year would be available in LEO, and very low cost solar panels could be assembled at GEO using asteroidal materials. The investment also would have a discounted net present value return on investment of 22% over twe...
Suborbital Freight, sometimes called Fast Freight, is delivery of high priority packages over int... more Suborbital Freight, sometimes called Fast Freight, is delivery of high priority packages over intercontinental distances in periods of approximately one hour. The vehicles required are usually rocket-powered and have total ideal velocities of around 7.5 km/second. Analysis of this market indicates that there are niches where commercial operations are possible and might even be profitable using today’s state-of-the-art technologies. The key requirements to capture this market are low nonrecurring costs, quick turnaround (<9 hours), and high reliability (0.999). This draft is a report on work in progress. The Fast Freight study will be completed before the STAIF-97 conference and results will be presented at that time.
A comparison of TSTO and SSTO space launch systems is made considering the investment decisions t... more A comparison of TSTO and SSTO space launch systems is made considering the investment decisions to be made for such systems. This comparison will be made using conceptual designs for such systems based upon Boeing current space launch studies. The comparison will include market investment considerations as well as cost and operability concerns.
Interstellar transportation over periods shorter than the human lifetime requires speeds in the r... more Interstellar transportation over periods shorter than the human lifetime requires speeds in the range of 0.2–0.3c. These speeds are not attainable using rockets, even with advanced fusion engines. Anti-matter engines are theoretically possible but current physical limitations would have to be suspended to get the mass densities required. Interstellar ramjets have not proven practicable, so this leaves beamed momentum propulsion as the remaining candidate. This paper reviews the state of beamed-momentum in-space propulsion and presents a point design system suitable for human exploration of nearby stars using today's physics and resources known to exist in the solar system. The total beam energy requirement for an interstellar probe mission is roughly 10 20 J , which would require the complete fissioning of one thousand tons of uranium assuming 35 percent power plant efficiency. This is roughly equivalent to a recurring cost per flight of 3.0 billion dollars in reactor grade enri...
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Papers by Dana G Andrews