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FINAL PREPARATIONS: 1968
Lunar Surface Experiments
Commander Jim Lovell practices the "barbell carry," transporting a
mockup of the lunar surface experiments package in a walkthrough of the
first traverse planned for Apollo 13. The black object on the right with
fins, is the radioisotope thermal generator (power unit).
During 1967 the Bendix Corporation and MSC ironed out the development
problem of the Apollo lunar surface experiments package (ALSEP), and the
project was on schedule for the first lunar landing mission. [see Chapter 6] But as the year wore on, doubts
about the ability of the astronauts to set up the instruments in the
time available,* expressed in July
by a Headquarters official,5 [see Chapter 7] arose in other quarters as well.
Planning for lunar surface operations called for one period of activity
in which the astronauts would collect a contingency sample, inspect the
lunar module, and familiarize themselves with the low-gravity
environment. During this excursion - whose length was limited by the
capacity of the portable life-support systems - they would scoop up 10
kilograms (22 pounds) of surface material and load it into the sample-
return container. No one was sure how much time these activities would
require. MSC tended to be very conservative in estimating how much work
astronauts could do under lunar surface conditions, and since it was
certain that setting up the experiments would take a good deal of time
and effort, deployment was not scheduled during the first extravehicular
period. "For planning purposes," preliminary plans called for
a second moon walk during which the crew would unload, lay out, and
connect the science instruments.6
As planning went on, however, and the limitations of time and
life-support systems became clearer, the flight of the planned group of
instruments on the first lunar landing mission became more doubtful.
Simulations showed that a suited astronaut had serious difficulty in
unloading the package from the lunar module. To complicate the situation
further, weight was a growing problem with the lunar module and
difficulties were developing with the radioisotope thermoelectric
generator that provided power for the experiments. By mid-1968 planners
were already discussing the need to develop a smaller, less complex
package for that flight, so that some minimum scientific return would be
realized.7
MSC's normal conservatism in matters of crew safety and mission success
grew even stronger during the summer. The more engineers and mission
planners looked at alternatives the more attractive a simplified plan
for lunar surface operations became. The first lunar landing would,
after all, be the most hazardous (potentially catastrophic) space
mission yet, and it would be done with a spacecraft that had not been
(and could not be) tested under conditions exactly duplicating the
mission. Houston's concern had its effect in Washington. In June George
Mueller asked Gilruth to schedule a simulation of instrument deployment
so that he could make his own evaluation.8 After this was completed in mid-August 1968, Sam
Phillips, Apollo program director at Headquarters, conferred with the
chairman of the Science and Technology Advisory Committee** on proposed changes in plans for the first
lunar landing. When they reached agreement, Phillips notified committee
members of the new plans. Instead of a 26-hour stay on the moon and
two-person excursions, he said, "it now seems prudent to limit the
lunar surface staytime to about 20 hours and the EVA [extravehicular
activity] to a single one-person excursion of 2 to 2 1/2 hours
duration." This decision was based on experience in Gemini, where
MSC had been unpleasantly surprised by the difficulty of working in null
gravity. Whereas previous plans had called for the astronauts to set up
a high-gain (strongly directional) antenna for television transmission,
conduct preliminary geological exploration, collect samples, and emplace
the lunar surface experiments package, mission planners now proposed to
curtail the geological exploration, to depend on the 64-meter antenna at
Goldstone, California, to pick up TV signals from a less directional
antenna that did not have to be deployed by the astronauts, and to carry
no scientific instruments at all. Phillips regretfully acknowledged that
much scientific information would be lost but noted that subsequent
missions would make up for it. Offsetting that loss would be operational
advantages that looked extremely attractive: an increase in the safety
margins for the lunar module's propulsion systems; maintenance of the
lunar module in a state of readiness for quick departure in an
emergency; and simplification of the training program, which was
becoming undesirably complex.9
Phillips's action was welcomed by most of the MSC officials directly
involved, but not by Wilmot Hess, director of science and applications.
Hess, who had been fighting the battle for Apollo science on many fronts
for the past two years, was dismayed by Phillips's proposals. In a
vigorous remonstrance he deplored the severe loss to lunar science and
the loss of credibility among the scientists that MSC would suffer if
the proposed changes were adopted:
What can I answer to the critics of the manned
program?. . . People in NASA and outside. . . have repeatedly told me
that no useful science had been done on Gemini and that none would be
done on Apollo. My answer has been that it . . . would start with the
lunar landings. This is not the case now. A person who says now that the
scientific program of Apollo could be carried out as well using the
Surveyor Block III spacecraft has a very good story. I don't know how to
answer him.
Hess strongly urged that the proposed single EVA be open-ended, lasting
up to three hours if all should go well, and carrying all the scientific
instruments:
. . . if there is a 50-50 chance of getting one
experiment deployed . . . it would be better to carry ALSEP and take the
chance of not deploying it rather than not carry [it] and . . . lose any
chance to do this important experiment.
He closed with a strong recommendation to carry several small, easily
deployed experiments on the first landing and to make a firm
announcement that the second lunar landing would include a 35-hour stay,
three EVAs, and the conduct of the entire science program: collection of
samples, deployment of the full package of surface experiments, and
carrying out the field geology program.10
In response to Hess's plea Phillips asked MSC to propose a contingency
science program for the first landing; this was prepared and reviewed at
MSC early in October. In discussions with Phillips and George Low, MSC
Apollo spacecraft program manager, Hess, won back some important points
for science. The new experiments package would contain three simple
instruments: a laser retroreflector, requiring no electrical power, with
which variations in the earth-moon distance could be measured with great
accuracy; a passive seismometer powered by solar panels; and a
solar-wind composition experiment, also passive and requiring very
little astronaut attention to set up. The astronaut on the lunar surface
would not spend time simply testing his mobility and agility, but would
carry out some productive scientific tasks while acclimating himself,
such as collecting and packaging samples and taking documentary
photographs of samples as they were collected. Hess forwarded his
proposals to Robert Gilruth and prepared a procurement plan for the new
set of experiments.11
On November 5, Headquarters approved the new package and authorized MSC
to modify Bendix's contract to build it. Manufacture could start before
the final terms were negotiated, as time was critical. Some difficulty
was expected in fabricating the laser reflector (an array of a hundred
individual "corner reflectors," internal corners of cubes made
of silica, polished to fine tolerances and precisely aligned) and MSC
was authorized to pursue parallel approaches with the University of
Maryland and the Air Force Cambridge Research Laboratory, both of which
were working on similar projects.12 The
new package would be called the "early Apollo scientific
experiments package," or "EASEP."13 Total funding for the package was $5.3
million, and delivery was to be scheduled for May 15, 1969.14 Formal assignment of EASEP to the first
landing mission was made by direction of the Apollo configuration
control board on December 5.15
Hess's vigorous advocacy saved a minimal scientific return for the first
lunar landing mission, and the original group of experiments - with some
changes - would be flown on all subsequent missions. Whether the dire
consequences he anticipated in the event of complete cancellation would
have materialized is debatable. As early as May 1968 the Planetology
Subcommittee of the Space Science and Applications Steering Committee
had been warned of such a possibility and had not objected; it merely
urged that a set of backup experiments be developed in parallel, to be
ready in case the complete package could not be flown.16 The scientists who were to conduct the
experiments agreed - after the fact - that the changes were acceptable
under the circumstances, but expressed understandable vexation because
they were not consulted before the decision.17 Still, the mood of many scientists outside
NASA was such that removing the lunar surface experiments from the first
mission might well have provoked a new storm of criticism of the Apollo
program.
* An additional question, raised by
MSC's Flight Operations Directorate, was whether any lunar module
systems should be turned off during the lunar stay. FOD favored keeping
critical systems running so that the astronauts could depart immediately
in case an emergency developed; this would require additional
consumables which would cut into LM weight margins. Minutes, Lunar
Missions Planning Board, May 19, 1967.
** Principal external advisory group
to the Office of Manned Space Flight, established by George Mueller in
1964.
5. Leonard Reiffel to Gen. S. C.
Phillips, "Flight Schedule for ALSEP and Related Matters,"
June 10, 1967.
6. Donald K. Slayton to Dir., Science and
Applications (MSC), "Apollo Lunar Surface Operations
Planning," Feb. 28, 1968.
7. Verl R. Wilmarth, "Summary
Minutes, Planetology Subcommittee of the Space Science and Applications
Steering Committee (Meeting No. 3-FY68), May 15, 16, 17, 1968";
Edward M. Davin to Mgr., Apollo Surface Expts. Program,
"Contingency Science Payloads," July 3, 1968; Richard J. Green
to MSC, attn.: John W. Small, "Science Payload Options," July
3, 1968.
8. George E. Mueller to Robert R.
Gilruth, June 5, 1968; Gilruth to Mueller, June 27, 1968.
9. Phillips to Dr. Charles H. Townes,
Aug. 31, 1968, with encl., letter to members of OMSF Science and
Technology Advisory Committee, same date.
10. George M. Low to G. W. S. Abbey,
"Lunar Mission Planning," Sept. 3, 1968; Wilmot N. Hess to
Mgr., Apollo Spacecraft Program (MSC), "Changes in Mission G
Plans," Sept. 4, 1968.
11. Hess to Dir. (MSC),
"Contingency Apollo Science Program," Sept. 30, 1968, with
encl., "Contingency Apollo Science Program Implementation
Plan" (preliminary), Sept. 27, 1968; idem, "Plans for
Alternate Science Program on First Apollo Lunar Landing," Oct. 4,
1968.
12. Mueller, TWX to MSC attn.: Robert R.
Gilruth, Nov. 5, 1968.
13. A. E. Morse, Jr., to Mgr., Apollo
program, "KSC support for the LM-5 Early Apollo Scientific
Experiment Payload (EASEP)," Nov. 12, 1968; Phillips to Gilruth,
Nov. 15, 1968.
14. Phillips to Gilruth, Nov. 15, 1968.
15. Phillips, TWX to MSC attn.: G. M.
Low, W. N. Hess, "Experiment Assignments to Lunar Missions,"
Dec. 5, 1968.
16. Wilmarth, "Summary
Minutes."
17. Gilruth to Hqs., attn.: E. Taylor,
TWX, "OSSA Activities-Weekly Report," Oct. 24, 1968.
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