[InclinedPlane]

3 of 3. The Shuttle is not reusable, it is at best refurbishable. In between launches the SRBs and the ET have to be replaced and the orbiter itself has to be processed including replacement of its main engines, draining of all consumables, and extensive inspection of each one of the thousands of thermal protective tiles. All in all the process takes months. This is not reusability in any meaningful sense of the word, it borders on a complete overhaul of the vehicle. Imagine if on landing a 747 it had to be drained of fuel, the engines replaced, the center fuel tank replaced.

This is a major factor in why it is so expensive to operate the Shuttles. They are not truly reusable, and the refurbishment in between launches takes so long and requires such an extensive permanent staff and facilities that the per-launch cost is astronomical. If the Orbiters were truly reusable then they could easily quadruple or more the number of flights per year for little increased total cost.