This repository has been archived by the owner on Jul 17, 2020. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 2
/
ch4-3.html
169 lines (152 loc) · 8.05 KB
/
ch4-3.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
<!DOCTYPE HTML>
<HTML>
<HEAD>
<title>Chariots For Apollo, ch4-3</title>
<meta http-equiv=Content-Type content="text/html; charset=UTF-8">
</head>
<BODY BGCOLOR="#FFFFFF">
<p>
<h2>Preliminary Designs for the Lunar Lander </h2>
<p>
Work at NASA's lead Apollo center on the excursion vehicle had started
in late 1961, when designers began looking at the advantages of
lunar-orbit rendezvous. But these had been analyses of general rather
than specific configurations. Wernher von Braun's researchers in
Huntsville had also studied concepts for soft landing. For landers
weighing several thousand kilograms (and thus presumably manned), they
considered liquid-fueled engines more practical than those using solid
propellants. Houston engineers also drew on studies conducted by the
Langley Research Center in Virginia. By mid-September 1961, Gilruth's
people had roughly worked out a mission plan and figured out the kind of
vehicle that might do the job. From September to December, they tried to
nail down systems operations more precisely, particularly in such areas
as propulsion and communications.<a href = "#source31"><b>31</b></a><p>
The mysterious nature of the moon's surface received much attention,
since a safe lunar landing presented some tricky design problems. Manned
Spacecraft Center engineers considered such things as the effect of
engine exhaust on the surface layer, the influence of dust layers on
landing-gear footpads, and surface dust effects on optical and radar
landing aids. Although a model of the lunar surface drawn from the best
available data was used for these engineering studies, Gilruth's men
realized that there were varying views among scientists about the lunar
surface characteristics, especially the depth of the dust layer.<a href
= "#source32"><b>32</b></a><p>
By early 1962, spacecraft specialists had begun to move beyond the study
phase. While others fought for their chosen mode, they worked out
details for building the lunar module and started preparing for its
procurement. The newly created Houston Apollo spacecraft office drafted
a lengthy document in April defending the hardware and operational
feasibility of lunar rendezvous and the excursion vehicle. Basic
concepts of the mission profile and docking and of storage arrangements
for the lander inside the spacecraft adapter were fairly firm. Many
aspects of guidance and navigation and of operations in lunar orbit were
well understood. Several theoretical vehicle shapes were depicted,
velocity requirements were delineated, vehicle weights (up to 9,200
kilograms, including a 25-percent contingency margin) were estimated,
and mission development plans, using the Little Joe II and the Saturn
C-IB and C-5, were considered.<a href = "#source33"><b>33</b></a><p>
William Rector was assigned to Frick's project office staff "to
start worrying about the LEM." Using command module documentation
as a guide, he wrote a work statement. Rector drew on technical
expertise from within the project office and from other center
organizations, particularly Max Faget's research and development
directorate. He relied heavily on advice from the Spacecraft Research
Division in preparing the procurement documents. Rector began with
"a real shoestring operation," a small group of specialists
for communications, propulsion, and overall configuration, and for
assembling information and writing the request for proposals.<p>
Early in May, Rector and his team finished the preliminary statement of
work and started on the formal proposal request. "I'll never
forget," he said later, "all we did was just sort of turn the
command module upside down and put a window and a propulsion stage in
it." From this point on Rector and his group continually revised
the proposal, to include additional information on visibility
requirements, crew location, and propulsion systems as it became
available. They also took first cuts at the guidance and communications
systems, among others, trying to work out the basic interrelationships
for each subsystem and to get them into the work statement.<a href =
"#source34"><b>34</b></a><p>
The spacecraft office wanted the work statement in its final form by
mid-July. When the early drafts went to Washington for review, Joseph
Shea in the Office of Manned Space Flight insisted that the vehicle
should be configured for unmanned, as well as manned, flight because
NASA might want to use it to ferry large payloads to the lunar surface.
Everyone in Houston, from Gilruth on down, claimed that such a lander
would be unreliable. The lunar module design should not be compromised
by throwing in this dual requirement.<p>
After a series of meetings, including a last-minute session with Gilruth
and Frick, Rector carried a work statement to Headquarters that left the
door open for future negotiations. To avoid further delay in
procurement, he had inserted a clause that obligated the contractor to
study the advantages and drawbacks of automatic versus manned modes and
to assist the agency in coming to a final decision. The procurement
documents were approved and issued to 11 aerospace
firms<a href = "#explanation1"><b>*</b></a> during the latter half of
July.<a href = "#source35"><b>35</b></a><p>
While Houston was getting ready to procure the lander, Shea's Office of
Systems was defending the agency's choice of lunar-orbit rendezvous
before the President's advisers and the public. This was a
time-consuming and harried process, a grinding day-by-day burden, that
began even before the official announcement in July.<p>
<p>
<hr>
<p>
<a name = "explanation1"><b>*</b></a> Companies invited to submit
proposals were Lockheed, Boeing, Ling-Temco-Vought, Northrop, Grumman,
Douglas, General Dynamics, Republic Aviation, Martin-Marietta, North
American, and McDonnell.
<p>
<hr>
<p>
<a name = "source31"><b>31</b>.</a> James P. Gardner, Harry O. Ruppe,
and Warren H. Straly, "Comments on Problems Relating to the Lunar
Landing Vehicle," ABMA Rept. DSP-TN-13-58, 4 Nov. 1958, passim, but
esp. p. 36; Donald C. Cheatham to Chief, Flight Ops. Div., and Head,
Apollo Projects Off., "Conference with Langley Research Center
personnel on problems related to lunar landing operations," 14 Nov.
1961; STG, "A General Description of the Apollo 'Bug'
Systems," 11 Sept. 1961; Owen E. Maynard, "A General
Description of the Lunar Excursion Vehicle's Systems for Excursions from
Lunar Orbit to Lunar Landing and Back to Lunar Orbit," STG, working
paper no. 1028, 29 Sept. 1961; Jack W. Small to Chief, Flight Systems
Div., STG, "Payload penalties and technical considerations for
implementing the LEV with communication functions in addition to those
which satisfy minimum requirements," 30 Nov. 1961; Richard B.
Ferguson, "Propulsion Requirements for Lunar Landing Missions
Employing a Detachable Lunar Lander," MSC, working paper no. 1038,
19 Dec. 1961.<p>
<a name = "source32"><b>32</b>.</a> Frank W. Casey, Jr., and Owen E.
Maynard, "A Hypothetical Model of the Lunar Surface for the
Engineering Design of Terminal Touchdown Systems," MSC, working
paper No. 1033, 30 Nov. 1961.<p>
<a name = "source33"><b>33</b>.</a> MSC, "Lunar Orbital Technique
for Performing the Lunar Mission," April 1962, passim, but esp. pp.
15-21, 57-61.<p>
<a name = "source34"><b>34</b>.</a> William F. Rector III, interview,
Redondo Beach, Calif., 27 Jan. 1970; MSC Weekly Activity Report for
Dir., OMSF, NASA, 29 April–5 May 1962, p. 11.<p>
<a name = "source35"><b>35</b>.</a> Rector interview; NASA,
"Request for Proposals on R&D for Lunar Excursion Module,"
news release, unnumbered, 25 July 1962; NASA, "Request for Proposal
on 'LEM,'" news release, unnumbered, 25 July 1962; "Apollo
Chronology," MSC Fact Sheet 96, n.d.
<P>
<HR>
<P>
<CENTER><A HREF="ch4-2.html">
<IMG SRC="previous.gif" ALIGN="left"
ALT="Previous Page">
</A>
<A HREF="ch4-4.html">
<IMG SRC="next.gif" ALIGN="right"
ALT="Next Page">
</A>
<A HREF="contents.html">
<IMG SRC="index.gif" ALIGN="middle"
ALT="Table of Contents"></A>
</CENTER><BR>
<HR>
<P>
</BODY>
<!--ADA TEAM 2001-->
</HTML>