THE FLYBACK F-1
The Flyback F-1 (fig. 6-8) is a winged, recoverable derivative of the Saturn V first stage. It was studied extensively in 1971 and Boeing proposed it for use as the first stage of the shuttle. Its development was estimated to cost $5 billion and to require a 7-yr lead time. It would replace the solid motors as the first stage of the HLLV. The propellants are mainly kerosene and oxygen. While the environmental consequences of kerosene are not as good as those of hydrogen, they are much better than those of solid propellant rocket motors. More research is needed to determine if this system could be made enviromentally sound for the 70-yr program of space colonization.
To guard against the possibility of cost underestimates in the earlier studies of the F-1 and to satisfy the need to develop a hydrogen-oxygen system for environmental reasons, this study assumes that the cost of the second generation system is $9 billion (rather than $5 billion) spread over a 7-yr period. Regardless of whether the F-1 or some other system is developed, performance characteristics are assumed to be a transportation cost to low Earth orbit of $55 /kg of freight and $80,000 per person.
Table 6-11 gives the transportation costs for people and freight to L5 and the Moon over the whole program.
TABLE 6-11 (gif format)
| Year | Freight to L5, $/kg | Freight to Moon, $/kg |
People to L5, $/person | People to Moon, $/person |
|---|---|---|---|---|
|
1 2 3 4 5 (a) 6 7 8 9 10 11 12 13 (b) 14 15 16 17 18 19 20 21 22 & later (c) |
--- --- --- 960 
480  110 |
--- --- --- 1920 792 182 |
--- --- --- 1,008,000 696,000 160,000 |
--- --- --- 1,644,000 900,000 206,000 |
(a) Before year 5 the program involves no transportation.
The Space Shuttle
and HLLV became available for use in year 5.
(b) O2 becomes available in space for rocket propellant.
(c) The second-generation shuttle becomes available.
