sentovic

One of the proposals that involved the "Lunar Crasher" braking stage. In theory, a large ( usually solid propellant ) stage was used to slow the lander on a direct ascent trajectory from earth. This stage was then jettisoned to crash on the moon, while smaller and more controllable liquid engines were used for final approach and landing. JPL used a scaled down version of this approach on the Surveyor unmanned lunar landers. After doing the brute force main braking, the solid motor was jettisoned to lessen landing weight. Small liquid engines finished the job. JPL also proposed a manned Lunar Surface Rendezvous mode, using the lunar crasher technique and a gigantic segmented solid rocket booster. That proposal suggested landing many payloads in an area selected for a manned landing. These unmanned supply, shelter, and return fuel carriers would be pre-positioned and verified remotely, before a manned ship was dispatched to land among them. The unmanned ships were also to include a beacon to guide in the manned craft and to provide live TV coverage of the manned landing.

Proposal for a nuclear powered lunar expedition. The need for excessive crew shielding is negated by using distance between the nuclear propulsive unit and the manned cabin. The atomic engine ( there was great faith placed in the development of such a system, back then ) lowers the crew module to the surface, then lands a safe distance away. The process is reversed for the return trip. No nuclear rocket engine developed beyond the ground-based static firing stage. None was ever proved practical. Contamination was such that the units are still isolated in the Nevada desert for radiation safety reasons. Appropriately, at Jackass Flats, Nevada.