Advantages Lunar orbit rendezvous

comparison of lunar lander sizes, langley study

the main advantage of lor spacecraft payload saving, due fact propellant necessary return lunar orbit earth need not carried dead weight down moon , lunar orbit. has multiplicative effect, because each pound of dead weight propellant used later has propelled more propellant sooner, , because increased propellant requires increased tankage weight. resultant weight increase require more thrust lunar landing, means larger , heavier engines.

another advantage lunar lander can designed purpose, rather requiring main spacecraft made suitable lunar landing. finally, second set of life support systems lunar lander requires can serve backup systems in main spacecraft.