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OCR for page 15
Summary
POLICY ASSUMPTIONS
The United States will have a sustained manned space launch
capability.
9. The present shuttle will have to assure float function at least
until the turn of the century.
3. An ELV production commitment will be made to achieve a mixed fleet
of launchers.
FLIGHT RATES
Three Orbiters can sustain a rate of ~ to 10 flights per year
after an initial buildup period of approximately ~ years providing:
(1) no Orbiter is lost or becomes inoperable, (~) adequate logistics
support exists, and (3) no problems exist that require extensive
downtime. A surge rate of 1? flights per year should be possible for
short periods of time for simple payloads and flight plans.
With a ~-Orbiter fleet the sustainable taught rate would be lL-lS
per year with a surge rate of 15 flights per year only if appropriate
ground support facilities are acquired.
In order to sustain such rates and take account of possible
contingencies, the shuttle scheduling should be based upon fewer
vehicles than are actually in the inventory by almost one Orbiter.
FLEET CONCEPT
If the space shuttle is to serve manned launch requirements for an
extended period of time, then it should be viewed in terms of a fleet
in the same manner as other transportation systems and consideration
must be given to vehicle attrition necessitating replacement Orbiters
over time. This will necessitate a balance between production rates
and replacement requirements.
15
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16
LAUNCH DEMAND
With the temporary cessation of shuttle flights, it is expected
that the backlog of manifested payloads will actually decrease as some
previously scheduled satellites will not be flown arid the DoD will
off-load many payloads for launch on ELVs.
_ . .
The heaviest launch demand arises for the Space Stationer
shuttle launches are anticipated during
phase--and, presuming schedules do not
be accommodated by 3 Orb iters . ~ ~
study groups currently reexamining the conf iguration of
While many military payloads are slated for launch
and the MLV, there is not an ELF launch capability to accommodate the
large number of space science or commercially contracted payloads. A
resolute ELV procurement effort by NASA, or other civil government
agency, is not yet in place but may be required to fulfill commercial
contracts and ~ASA's space science program'. Unless or until a
commercial launch vehicle industry comes into existence, however, an
extensive private launch industry is not likely to arise before the
l990s .
3-year construction
^, this could not in itself
This situation
the Station.
on the Titan IV
PAYLOAD PARTITIONING
Partitioning of payloads between the shuttle and ELVs has been
materially affected because NASA is not funded at present to procure
ELVs. Even in the short run, some additional off-load~ng of
DoD-related payloads may be in order when alternatives are available.
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Appendixes
· 6
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6
Representative terms from entire chapter:
space science
