| Construction of the OBS would be highly modular, with the outer shell made from 10m2 panels, covered with a skin of aluminised Mylar. The structure would also provide tank farms for liquid oxygen and hydrogen propellants, accommodation for construction crews, and fuel cells to provide the base load power. Large doors at either end provide access for vehicles, while payload loading doors along the side enable cargo from docked SKYLON vehicles to be transferred using manipulator arms. An enclosed structure has several benefits; it provides protection from micrometeoroids and space debris, whilst also capturing any loose items within and therefore not adding to the problem. It also enables the internal volume to be lit with floodlights, as the OBS will orbit the Earth approximately every 90 minutes, half of the time being in darkness. Suitably arranged internal lighting would alleviate this problem. Vehicles under construction within the OBS would be tethered, while manipulator arms, attached to longitudinal rails, would be used to transfer crews and material as needed. |  | 
Assembly Dock Structure
(click for larger image) |
