Exploring the Unknown: Selected Documents in ... - The Black Vault

574
Project Apollo: Americans to the Moon
Document II-27
July 17, 1962
Dear Jim:
As I agreed to do during our recent meeting, I am forwarding Don
Hornig’s informal summary of the Space Vehicle Panel’s views as presented to
you and your staff at that time. I would also like to take this opportunity to put
down, more or less systematically, the substance of my own ideas: these overlap in
some respects there of the Panel, and have been at least in part passed on to you
verbally during the last two weeks.
First, I think that the final lunar mode choice must provide sufficient
payload margins to have a reasonable chance of coping with realistic shielding
requirements to meet solar flare radiation hazards which will be approaching
their cyclical peak at about the same time that the manned lunar mission will be
attempted unless other means are developed to cope with this serious problem.
Also, it is possible that exposure to zero-g conditions for the time intervals in
this mission may be found to present serious crew problems. Clearly, a mission
mode choice at this time must assume that this may turn out to be so, and should,
therefore, not exclude sufficient growth capability to offer some chance of dealing
with such a difficulty. Accordingly, I feel that both of these potential problem
areas should be as thoroughly explored as present scientific knowledge makes
possible. It seems to me that a combination of Jim Van Allen’s group and of STL
could supply a competent team to survey the flare hazard problem.
The matter of which mission mode is most consistent with the main
stream of our national space program, and therefore the one most likely to be
useful in overtaking and keeping ahead of Soviet space technology, is also one
that I believe requires further consideration. For example, if LOR is chosen and
the NOVA slipped by two years, then the U.S. will most likely not have an escape
capability significantly above 90,000 pounds until 1971 or 1972 at the earliest.
With LOR and C-5 Direct, on the other hand, a capability of 160,000 pounds to
escape will be available in 1966 or early 1967. Which of these situations, broadly
considered, is best for the [2] U.S. posture in space? Similarly, the question of
which mode is likely to be most suitable for enhancing our military capabilities in
space, if doing so should turn out to be desirable, should be reviewed with care.
The Space Vehicle Panel considered this item only casually and, as far as I know,
your mode studies had no inputs at all from the DOD in this area. Accordingly, I
see a need for an appropriate team of engineers and scientists to explore this area
on a time scale compatible with the LOR proposal period.
Thirdly, neither the Space Vehicle Panel nor your staffs, insofar as the
data presented to us is made clear, delved adequately into the likely effects of
environmental stresses on the crew during the journey, and therefore with the
effects on crew capabilities to cope either with the normal or the conceivable
emergency conditions to be encountered during various phases of each mode. I
would certainly recommend that these matters be reexamined in greater technical