OFT Orbital Ferry Tug

advanced orbit shuttling technologies - notes

The requirements for shuttling through the Earth's atmosphere from the surface to space orbit and back, must be met from better efficient and benign utilization of Earth resources, that the process may be accomplished on large scale for the immediate decades.

Subsequent decades may see utilization of similar technologies augmented with bulk launchers from Earth-orbiting manufacturing stations supplied from moon bases and near-Earth-orbit asteroid collectors, and by mega-booster launchers from Earth: boosters so large they ride on the extended WIG wing-in-ground effected air pressure pocket below, to high altitude: the pressure pocket may be dynamically pumped by sculted shaped and synchrony-aimed reflected low-frequency sound wave focused beneath the mega-booster, above the hundred mile launch path - the audio foot-print effect to Earthers may be like a quick dunking in 2 meters of water: 0.2 bar or 20% of an atmosphere: shy of ear-popping: The basic ground shape is flat, but additional wave-distribution sculpting can improve the recontainment coefficient of the open-space LF-wave soliton diffraction-dissipation.

Contemporary efficient use of launch energies suggest keeping rocket engines only in space, and utilizing HSST air-engines upto suborbit, where the rising HSST meets the OFT, exchanges passengers, freight, fuels and propellant, then arches back to Earth landing for another cycling, while the OFT continues on repropellanted power back up to full orbit speeds and altitudes, up to the optimal station altitude - then remains available until the next launch cycle: a significantly more effectual scheme to keeping long-term space crews well-equipped.

[Similar efficiency discussions on other aspects of space missions are on my politics web-site: to land or not on Mars; to 80AU deep space]

I've advocated for advancement of outer-space ventures, the stepped approach to launching to LEO [Low Earth Orbit] - and suggested it should be called the McAuliffe Stepped Launch, recalling the first public passenger on the broken NASA mission STS-51-L. The major weights in this decision are: the rocket engines, which design-compromised are less efficient in the atmosphere as well as in space, the atmospheric design of the shuttle, which [wings, wheels] mass is accelerated and decelerated from Earth rotation speed to and from orbit speed each round trip to space, and again accelerated and decelerated for each orbit change, especially for higher altitudes which are needed for longer space-station orbit longevity, and [mass] unused once in orbit, and the outer-space(r) design of the Shuttle, which extra mass is lifted from Earth to orbit each time, and then, to top-off the space-ability wastefulness, the Shuttle is unavailable to space station residents for the vast duration of the extent of their stay!

The Shuttle must be replaced by an OFT [Orbit-Ferry-Tug] made predominantly available to the space station residents, except when transferring passengers, propellants, and freight from an Earth-Space Launch vehicle, and returning passengers and special products, which [atmospheric launcher] under such improved regime, no longer needs to carry space-rocket engines, nor needs to attain orbit speed: the OFT will do the space-side of the equation with more efficient space-rocket engines, and its Earth-compatibility will be limited to passengers, a one-time-emergency-reentry [a soft-fail mode] ... the transfer between vehicles will take place inside the edge of the Earth's atmosphere, where incoming meteorites appear readily on radar watching for plasma-tails, thus greatly increasing overall safety, at greatly improved efficiency.

As the first contemporary manned-venturers into the solar system we should not decline to do too much good work for fear of raising the good-government grading-curve.

[more construction]

While NASA re-fleets to the X-33 SSTO Single-Stage-To-Orbit (new) spacecraft, and skirts nearing mechanical obsolescence and financial retirement, the Space Agency perspective condenses from its '60's space-exploration expectancies, to exploration of Earth, by and for the Earth, leaving deep-space agenda to probe-missions wanting computing power for its next generation of [NASA] fact-checking technologies.

To lower the high-altitude cost of space-flight, and regain stabler orbital aspects and elements, we recognize the adage, "first-thinks-first" ... space-launch, like mathematics, starts from a firm understanding, aspires to great heights, and does not turn back: it takes no Earthly weights of fiction, lest it fall-back and plummet to worse depths.

A space-vehicle needs its passenger and cargo holds (fuselage), its engines, its fuel, and its ancillary features {wings, heat shields, etc.}. In the atmosphere, fan-jet (type) engines are fuel-efficient, but only to low-Mach speeds (~2000mph), thereabove requiring scram-jet (super-sonic ram-jet), until the upper atmosphere requires rocket (fuel-plus-oxidizer) as there is insufficient air in low-Earth orbit (designated LEO) to supply the oxidizer (or fuel if hydrogen were scooped-in directly). Each of these engines adds weight (as increasingly useless payload) and consequently more fuel, which itself adds weight (up to the limit of gainliness). We can though, reasonably leave as much as possible 'up' in orbit, and then use it when the space-going vessel gets there, into orbit or near-enough to have the equipment brought down to meet, exchange payloads, and return to full orbit. In other words, leave the rocket engines in orbit (and a passenger cabin, and freight-payload poles and tethers); and choosing the most efficient space-engine (not the same as a lower-atmospheric rocket engine: it has a larger nozzle), run it in outer-space as a orbital-ferry-tug (also called an orbital-transfer-vehicle), which can be used continually among the space-station's facilities, and occasionally return and retrieve passengers and freight exchanged with an up-coming 'air' craft-to-space (call it an SSTS single-stage-to-suborbit). Keeping multiples of the OFT's orbiting increases the abilities of the astronauts to run quickly between any and all LEO facilities (even doubling as an alternative transport for the Russian's MIR cosmonauts: the OFT's can run errands and mercies between any similarly specified orbits, tripling as emergency descent 'escape' vehicles only in the event of a space-calamity (a failed SSTS, SSTO, Shuttle, passenger rocket, etc.) ... it's advantage is that it's there, ready to use.

Without the excess engine weights, the SSTS can carry more payload weight. . . .

[more construction]

A premise discovery under the title,

Grand-Admiral Petry
'Majestic Service in a Solar System'
Nuclear Emergency Management

© 2000 GrandAdmiralPetry@Lanthus.net