CLLARE mission overview
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[edit] Overview
In the current version of the CLLARE mission plan, a single launch is used to carry a single stack of hardware into Low Earth Orbit. This conceptual centre of this stack is the CLLARE Command Module (CM), which has attached behind it an Orbital Support Module (OSM) to provide supplies for a long-duration flight, a Propulsion Module (PM) for propulsive maneuvers, and in front of it the CLLARE Lunar Lander (LL) for the actual lunar landing. The PM is used to lift the stack out of LEO and onto a free-return lunar trajectory, and then to put the stack into a low lunar orbit once it arrives. The astronaut then transfers from the CM to the LL via a spacewalk, uses the LL to descend to the lunar surface and, after lunar EVA, to return to the rest of the orbiting stack. The PM is then used to put the PM-OSM-CM combination on an Earth-bound trajectory. The LL is left in lunar orbit. Prior to reentry of Earth's atmosphere, the CM separates from the rest of the remaining stack and safely reenters, while the other modules burn up.
[edit] Parking orbit
A command module with an attached lunar lander are launched into a roughly circular LEO parking orbit using a Selene 3 modular booster assembly. Possibly the two are launched already docked as a single unit (similar to the Apollo CSM launch arrangement) or possibly the two are launched separately and dock in LEO. While in this parking orbit, various checks of the spacecraft are performed before proceeding to the next phase.
[edit] Trans Lunar Injection
If all is well for mission continuation, the LL's engine is used to perform a trans lunar injection burn, putting the spacecraft on a course for the moon. This burn requires a delta v of a little more than 3 km/s. At the completion of this burn, the CM/LL pair will be on a free return trajectory: with no further alterations to its course, the moon's gravity will reflect the CM's trajectory through 180 degrees, sending it back toward the Earth. This arrangement means that damage to the spacecraft during travel to the moon which incapacitates the CM's RCS or the LL's engine will not leave the astronaut unable to return to Earth.
[edit] Lunar capture
When the CM/LL is sufficiently close to the moon (after roughly 3 days of travel), if all is well for mission continuation the LL performs a lunar capture burn, placing the CM/LL into a lunar orbit. This requires a delta v of ~1 km/s.
[edit] Extra Vehicular Transfer
The astronaut opens the CM ingress/egress hatch and transfers to the LL. The astronaut remains tethered to the CM during this trasnfer (but disconnects the tether after securing themself to the LL chair).
[edit] Lunar descent
The astronaut separates the LL from the CC and uses the lander's RCS and engine to perform a descent to the lunar surface, guiding the LL to a pre-selected landing site.
[edit] Lunar exploration
After landing, the astronaut climbs down the steps of the lander and performs pre-planned lunar EVA for a pre-planned time.
[edit] Lunar ascent
Upon completion of lunar EVA, the astronaut returns to the lander and uses the lander's RCS and engine to return to orbit at the same altitude as the CM. A series of orbital maneuvers are used to bring the LL sufficiently close to the CM to allow a transfer back.
[edit] Trans Earth Injection
The LL's engine performs a trans Earth injection burn, accelerating the CM just beyond the moon's escape velocity and on a course for Earth. This requires a delta-v of roughly 800 m/s.
[edit] Reentry
Can we achieve a safe and stable reentry using purely aerodynamic control (c.f Mercury's "spoiler", SpaceShipOne's "shuttlecocking", Apollo's careful centre of mass positioning to achieve a reentry altitude that generates lift) or will we need to budget on having enough RCS propellant left for control?
We need to do more research on the paraglider option - old Gemini documentation should be good for this.
[edit] Recovery
There seems to be moderately strong support on the forums for a water landing rather than a solid ground landing. There are some concerns with regards to the extra effort involved in an ocean splashdown (need for a heavy lifting helicopter or large boat, the risk of a drowned astronaut if the landing site is too far from plan). The use of large lakes has been proposed as a compromise.
