Spacecraft Design Options

We're finding zillions of options while working out 3-D renderings. A non-encyclopeedic list:

• Lunar Transfer Vehicle
  • Overall Configuration
    Optimize for later use as free-flyer or space station laboratory, methods for refueling, methods for swapping tanks
  • Propulsion
    Engine selection, number of engines, engine arrangement
  • Fuel and oxydizer tanks: number, geometry, arrangement, insulation, thermal protection scheme, launch packaging, pumps vs. gas pressurization, plumbing layout
  • Electrical power: fuel cells, batteries, to have photovoltaic arrays or not, geometry of photovoltaic arrays,
  • Maneuvering thrusters: buried in module or thruster clusters, rocket motor selection, geometry of fuel tanks, plumbling layout, engine gimbaling vs. thrusters to get the thrust vector through the center of gravity
  • Forward service module: length, functions, geometry
  • Command module: source for pressure vessel, interior layout, airlock vs. depressurizing the whole module, air cooling vs. liquid cooling for electronics
  • Thermal control: body-mounted radiators vs. paddles, working fluid (ammonia, freon, something else)
  • Windows: periscopes, simple windows, shades,
  • External cameras: size, type, location, method of attachment to LTV structure, supporting lights
  • Control software: completely autonomous vs. ground control
  • Antennas: how many, antenna geometry, where to mount them, design of antenna mount, automatically deployed or installed by crew
  • Structures and mechanisms: automated or manual, selection of design for each item, material, off-the-shelf vs. custom hardware
• Airlock
  • Separate unit or part of moon base hab module, selection of berthing mechanism, blow-down or recovery pump, suit stowage in airlock or in main module
• Moon Base
  • Pressure vessel: Source (anything better than SPACEHAB?), horizontal vs. vertical orientation, size (1, 2, or 3 modules), inflatable vs. rigid (inflatable technology might advance; even if not, the idea keeps coming up)
  • Power supply: fuel cells, batteries, photovoltaic, radioisotope thermal generator, solar dynamic
  • Protection: pile on moon dust directly vs. erecting a tent, geometry of tent, periscopes vs. movable awnings to protect windows
• Descent Stage
  • Fuel tanks: geometry and arrangment (sphere, cylinder, torus), clustered or stacked, material, single use or design for later use as moon base gas storage
  • Primary structure: I-beams, tubes, rely on fuel tank material
  • Insulation: beta cloth, gold foil, combinations of these, other material, wrap tanks individually or surround the whole package
  • Overall geometry: match SPACEHAB geometry or size for launch as individual package, embedded ascent stage vs side-saddle
  • Engines: rocket motor selection, cryogenic vs. hypergolic fuel, number of engines, nozzle expansion (hence nozzle size and geometry)
  • Maneuvering thrusters: use ascent stage thrusters during descent?; also same options as LTV maneuvering thrusters, but with different considerations
• Landing Gear
  • Geometry: springs vs mechanisms, options for requirements (how much lateral and vertical motion at touchdown; drives geometry), number of gear (3, 4, or 6), size of landing pads, design of contact probes
  • Mechanisms: springs vs. shock aborbers, method of rigidization on lunar surface; automated vs. manuually deployed; launched with descent stage and deployed or launched separately and installed; shock aborbers vs. compression members
• Ascent Stage
  • Geometry: embedded in descent stage vs side-saddle, open vs bubble enclosure to protect crew from moon dust, crew arrangement, crew standing vs lying down
  • Tanks: same issues all LTV and descent stage
  • Engines: number, cryogenic vs hypergolic
  • Attitude control: thrusters vs. engine gimbaling vs. differential thrust vs. vanes in engine plume vs. variable nozzle geometry
  • Antennas: type, geometry, location
  • Rendezvous radar: antenna design, antenna location
  • Thrusters: location, clusters vs. individual embedded thrusters

This is just a list of options for the one mission to get the moon base set up. We also have options for precursor and subsequent flights: all those ways to get rovers and camera robots up there, perhaps Earth orbit shakedown crusies for both unmanned and manned spacecraft, unmanned and manned translunar flights.