redgoals.manned TheuseofapermanentlyLEOstation asaSolarSystemexplorationbaseandasasupport stationfor tendedfree-flyingsatellites unmannedmeans thattowardtheendofthiscenturymanyof characteristicsmannedand unmannedspaceendeavorswill blend together. Modularize equipment. Modularization of equipment reduces the mass of material that must be transported to and from orbit for repair and replenishment of orbital facilities. This is because only defective or depleted modules FREE SATELLITES
l
SHUTTLE-T_
PROPELLANT FREE-FLYER MANUFACTURE
CO-ORBITING TENDED SATELLITES
MULTI
need be handled rather than the entire system mass is higher for modular designs, tenance mass is significantly reduced. The an existing facility to accept new capabilities plified through the use of plug-in modules. and replacement already are prime candidates for early automation and these procedures are streamlined by modularization. Both station growth and the multiplication of
capabilities become more feasible since the entire system need not be replaced as parts become inadequate or obsolete. The sizes of Spacelab and the Shuttle payload bay suggest a practical size limit for modules. Modularization is not intended to replace space fabrication of stations and equipment but is to be used in parallel with on-orbit construction.
SPACE ]
TELESCOPE
[PR-ESSURIZED SPACE LAB]
J
1
system. Overall but system mainmodification of is greatly sim- Parts installation
DEDICATED APPLICATION
PURPOSE LAB AND lASSEMBLY [/ AND PLATFORMS PLATFORM SAMPLE
I SCIENCE/ AND J I OBSERVATION QUARANTINE
STAGING BASEII STATION
!_ i
LARGE SPACE MULTIPURPOSE MANNED PLATFORMS
LEO STATION (WITH ASSOCIATED FREE FLYERS
]
SMF and PRODUCTS
Figure 7.5.-Details of LEO station development.
