The Apollo Spacecraft - A Chronology.|
Advanced Design, Fabrication, and Testing
February 1Pacific Crane and Rigging Company received a NASA contract, worth $8.3 million, to install ground equipment at Kennedy Space Center's Saturn V facility, Launch Complex 39. On the following day, the Army Corps of Engineers awarded a $2,179,000 contract to R. E. Carlson Corporation, St. Petersburg, Fla., to modify Launch Complex 34 to handle the Saturn IB.
Astronautics and Aeronautics, 1965, pp. 48, 52.
February 2-3The Apollo-Saturn Crew Safety Panel decided on a number of emergency detection system (EDS) and abort procedures for the early Apollo flights:
"Summary of Proceedings, Apollo-Saturn Crew Safety Panel Meeting No. 11, 2-3 February, 1965," February 4, 1965.
February 3ASPO established radiation reliability goals for Apollo. These figures would be used to coordinate the radiation program, to define the allowable dosages, and to determine the effect of radiation on mission success. The crew safety goal (defined as the probability of a crewman's not suffering permanent injury or worse, nor his being incapacitated and thus no longer able to perform his duties) was set at 0.99999. The major hazard of a radiation environment, it was felt, was not the chance of fatal doses. It was, rather, the possibility of acute radiation sickness during the mission. The second reliability goal, that for success of the mission (the probability that the mission would not be aborted because of radiation environment), was placed at 0.98.
These values, ASPO Manager Joseph F. Shea emphasized, were based on the 8.3-day reference mission and on emergency dose limits previously set forth. They were not to be included in overall reliability goals for the spacecraft, nor were they to be met by weight increases or equipment relocations.
Memorandum, Joseph F. Shea, MSC, to Assistant Director for E. and D., "Apollo Radiation Reliability Goals," February 3, 1965.
February 4A device to maintain the spacecraft in a constant attitude was added to the LEM's primary attitude control system (ACS). The feature brought with it some undesirable handling characteristics, however: it would cause the vehicle to land long. Although this overshoot could be corrected by the pilot, and therefore was not dangerous operationally, it would require closer attention during final approach. The attitude hold, therefore, hardly eased the pilot's control task, which was, after all, its primary function. Instead of moving the device to the backup ACS (the abort section), the Engineering Simulation Branch of MSC's Guidance and Control Division recommended that the system be modified so that, if desired, the pilot could disengage the hold mechanism.
Memorandum, Clarke T. Hackler, MSC, to Chief, Guidance and Control Division, "Evaluation of LEM modified (zero overshoot) rate command-attitude hold control mode," February 4, 1965.
February 4-11After considering possible impacts, MSC directed North American to implement real-time commands to the up-data link equipment on command modules 012 and 014.
MSC, "ASPO Weekly Management Report, February 4-ll, 1965."
February 4-11MSC questioned the necessity of using highly purified (and expensive) fuel-cell-type oxygen to maintain the cabin atmosphere during manned ground testing of the spacecraft. The Center, therefore, undertook a study of the resultant impurities and effect on crew habitability of using a commercial grade of aviation oxygen.
Ibid.; memorandum, Robert E. Smylie, MSC, to Chief, Environmental Physiology Branch, "Breathing oxygen for Apollo Command Module ground testing in Airframe 008," March 15, 1965.
February 5SM 001's service propulsion engine was static-fired for 10 sec at White Sands. The firing was the first in a program to verify the mission profiles for later flight tests of the module. (SM 001 was the first major piece of flight-weight Apollo hardware.)
MSC News Release 65-18, February 5, 1965; TWX, M. L. Raines, WSMR, to NASA Headquarters, MSC, MSFC, and ASPO Field Test Office, Cape Kennedy, Fla., "Airframe 001 First Firing," February 6, 1965.
February 8MSC deleted the requirement for a rendezvous radar in the CSM.
MSC, "Minutes, Configuration Control Board Meeting No. 5," February 8, 1965.
February 8MSC, North American, and Grumman reviewed the results of Langley Research Center's LEM-active docking simulation. While the overhead mode of docking had been found to be acceptable, two items still caused some concern: (1) propellant consumption could exceed supply; and (2) angular rates at contact had occasionally exceeded specifications. Phase B (Grumman's portion) of the docking simulations, scheduled to begin in about two weeks, would further investigate these problems. Langley researchers also had evaluated several sighting aids for the LEM and recommended a projected image collimated (parallel in lines of direction) reticle as most practicable. Accordingly, on March 9, MSC directed Grumman to incorporate this type of sighting device into the design of their spacecraft.
Letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Results of LEM active docking simulation at Langley Research Center," March 9, 1965.
February 8Development tests recently completed by AiResearch on the water evaporator control system for the space suit heat exchanger disclosed its inadequacy because of its slow response time. To solve this problem, AiResearch and North American proposed an alternate control system approach similar to the glycol evaporator scheme used elsewhere in the environmental control system. This alternate design, which was tested and appeared a more desirable approach, would be incorporated on airframes 008 and 012 through Block II spacecraft. No schedule impact was anticipated.
"ASPO Weekly Management Report, February 4-11, 1965"; memorandum, Frank E. Samonski, Jr., MSC, to Chief, Test Division, "A14-033 requirements for Airframe 008 testing," February 8, 1965.
February 8NASA invited 113 scientists and 23 national space organizations to a conference at MSC to brief them on the Gemini and Apollo missions. As a result of the conference, NASA hoped to receive proposals for biomedical experiments to be performed in Gemini and Apollo spacecraft.
MSC News Release 65-21, "Foreign Scientists Invited to Conference on Apollo Experiments," February 8, 1965.
February 9North American completed the first ground test model of the S-II stage of the Saturn V.
Space Business Daily, February 9, 1965, p. 195.
February 10ASPO and the MSC Instrumentation and Electronic Systems Division (IESD) formulated a program for electromagnetic compatibility testing of hardware aboard the CSM and LEM. The equipment would be mounted in spacecraft mockups, which would then be placed in the Center's anechoic chamber. In these tests, scheduled to begin about the first of September, IESD was to evaluate the compatibility of the spacecraft in docked and near-docked configurations, and of Block I spacecraft with the launch vehicle. The division was also to recommend testing procedures for the launch complex.
Memorandum, R. S. Sawyer, MSC, to Chief, Systems Engineering Division, "Test Philosophy for CSM/ LEM Electromagnetic Compatibility Test to be performed in the Anechoic Chamber Test Facility at MSC," February 10, 1965.
February 10ASPO evaluated Grumman's proposal for an "all battery" system for the LEM descent stage. ASPO was aiming at a 35-hour lunar stay for the least weight; savings were realized by lessening battery capacities, by making the water tanks smaller, and by reducing some of the spacecraft's structural requirements.
Letter, Thomas J. Kelly, GAEC, to MSC, Attn: W. F. Rector III, "Submittal of Additional Information Relative to the Lem 'All-Battery' Study," February 10, 1965, with enclosures.
February 11A drop test at EI Centro, Calif., demonstrated the ability of the drogue parachutes to sustain the ultimate disreefed load that would be imposed upon them during reentry. (For the current CM weight, that maximum load would be 7,711 kg [17,000 lbs] per parachute.) Preliminary data indicated that the two drogues had withstood loads of 8,803 and 8,165 kg (19,600 and 18,000 lbs). One of the drogues emerged unscathed; the other suffered only minor damage near the pocket of the reefing cutter.
"Apollo Monthly Progress Report," SID 62-300-35, pp. 3-4; MSC, "ASPO Weekly Management Report, February 11-18, 1965."
February 11-18MSC modified its bubble helmet design to fit on an International Latex "state-of-the-art" space suit. A mockup of the helmet was used in don doff tests. Mean donning time was 4.2 sec; doff time averaged 1.47 sec. Further tests would be performed when a prototype helmet was completed (expected by February 26).
"ASPO Weekly Management Report, February 11-18, 1965."
February 11-18Hamilton Standard, the extravehicular mobility unit contractor, completed a two-week wearing test of the Apollo liquid-cooled undergarment. Investigators found that the garment could be worn for the entire lunar mission without any serious discomfort.
February 11-18To make room for a rendezvous study, MSC was forced to end, prematurely, its simulations of employing the LEM as a backup for the service propulsion system. Nonetheless, the LEM was evaluated in both manual and automatic operation. Although some sizable attitude changes were required, investigators found no serious problems with either steering accuracy or dynamic stability.
February 11-18North American selected the Ordnance Division of General Precision Link Group to supply the panel thrusters for the spacecraft lunar adapter.
February 11-18Evaluations of the three-foot probes on the LEM landing gear showed that the task of shutting off the engine prior to actual touchdown was even more difficult than controlling the vehicle's rate of descent. During simulated landings, about 70 percent of the time the spacecraft was less than 0.3 m (1 ft) high when shutdown came; on 20 percent of the runs, the engine was still burning at touchdown. Some change, either in switch location or in procedure, thus appeared necessary to shorten the delay between contact light and engine cutoff (an average of 0.7 sec).
February 12MSC relayed to NASA Headquarters North American's cost estimates for airlocks on the Apollo CM:
During late February and early March, North American completed a conceptual design study of an airlock for the Block I CMs. Designers found that such a device could be incorporated into the side access hatch. A substitute cover for the inner hatch and a panel to replace the window on the outer hatch would have to be developed, but these modifications would not interfere with the basic design of the spacecraft.
TWX, Joseph F. Shea, MSC, to NASA Headquarters, Attn: Samuel C. Phillips, February 12, 1965; "Apollo Monthly Progress Report," SID 62-300-35, pp. 17-18.
February 12MSC's Systems Engineering Division (SED) requested support from the Structures and Mechanics Division in determining the existence or extent of corrosion in the coolant loops of the SM electrical power subsystem (EPS) and the CM and LEM environmental control subsystems (ECS), resulting from the use of water glycol as coolant fluid. Informal contact had been made with W. R. Downs of the Structures and Mechanics Division and he had been given copies of contractor reports and correspondence between MSC, North American, and MIT pertaining to the problem. The contractors had conflicting positions regarding the extent and seriousness of glycol corrosion.
SED requested that a study be initiated to:
February 15A study by General Electric affirmed the necessity for the steerable S-band antenna for communications between the spacecraft and the ground at lunar distances. Communications margins were so small that, at those distances, any degradation of equipment would seriously affect the spacecraft's contact with earth.
Letter, E. J. Merrick, GE, to William A. Lee, "S-Band Communications Requirements Study," February 15, 1965, with enclosure: "CSM-LEM Directional Communications Antenna Relationship to Communications Margins and Mission Requirements."
February 16Crew Systems Division (CSD) informed the Astronaut Office that the requirements submitted by Astronaut Michael Collins on February 5 had been included in the Block II suit program plans. Those requirements for astronaut training suits were:
Memorandum, Richard S. Johnston, MSC, to Assistant Director for Flight Crew Operations, Attn: D. K. Slayton, "Apollo Block II training suits," signed E. L. Hays, February 16, 1965.
February 16In the first of a series of manufacturing review meetings at Bethpage, N.Y., it was learned that Grumman's tooling program was behind schedule (caused primarily by engineering changes). Tool manufacturing might recoup much of the lost time, but this process was highly vulnerable to further design changes. Completion of tooling for the ascent stage of LTA-3 was now set for late April, a production delay of about two months.
Letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "LEM Manufacture Review Meetings Minutes," March 3, 1965, with enclosure: "Minutes, LEM Manufacturing Review Meeting, February 16, 1965."
February 16In a memorandum to ASPO, Samuel C. Phillips, Apollo Program Director, inquired about realigning the schedules of contractors to meet revised delivery and launch timetables for Apollo. Phillips tentatively set forth deliveries of six spacecraft (CSM/LEMs) during 1967 and eight during each succeeding year; he outlined eight manned launches per year also, starting in 1969.
Memorandum, Samuel C. Phillips, NASA, to MSFC, MSC, and KSC, Attn: Directors, "Apollo Delivery and Launch Schedules," February 16, 1965, with enclosures.
February 16A Saturn I vehicle SA-9 launched a multiple payload into a high 744 by 496 km (462 by 308 mi) earth orbit. The rocket carried a boilerplate (BP) CSM (BP-16) and, fitted inside the SM, the Pegasus I meteoroid detection satellite. This was the eighth successful Saturn flight in a row, and the first to carry an active payload. BP-16's launch escape tower was jettisoned following second-stage S-IV ignition. After attaining orbit, the spacecraft were separated from the S-IV. Thereupon the Pegasus I's panels were deployed and were ready to perform their task, i.e., registering meteoroid impact and relaying the information to the ground.
NASA News Release 65-38, "Saturn I to Launch Pegasus Meteoroid," February 15, 1965; TWX, E. R. Mathews, KSC, to NASA Headquarters, MSFC, MSC, and MSFC Resident Manager, Sacramento, California, subject: "CLN SA-9 Apollo Flash Report No. 2," February 18, 1965; Astronautics and Aeronautics, 1965, pp. 71-72.
February 16NASA awarded an $8,879,832 fixed-price contract to the Univac Division of Sperry Rand Corporation for digital data processors for the Apollo project. Univac also would assist in modifying extant computer programs to meet Apollo requirements.
NASA News Release 65-50, "NASA Buys Univac Data Processing for Moon Project," February 16, 1965.
February 16MSC announced a realignment of specialty areas for the 13 astronauts not assigned to forthcoming Gemini missions (GT 3 through 5) or to strictly administrative positions:
February 16-March 15The CM's waste management system demonstrated its feasibility under zero-g conditions during flights from Wright-Patterson Air Force Base. The system successfully contained both solid and liquid wastes and did not leak even when filled to capacity.
"Apollo Monthly Progress Report," SID 62-300-35, p. 7.
February 17The U.S. Navy Air Crew Equipment Laboratory began testing the Gemini Block I Apollo space suit in a wide range of environmental temperatures to determine the comfort and physiological responses of the wearer. The program, delayed because of difficulties with humidity control, was to be completed in three to four weeks.
"ASPO Weekly Management Report, February 11-18, 1965."
February 17Ranger VIII, a lunar probe carrying six television cameras, was launched from Cape Kennedy by an Atlas- Agena B vehicle. The spacecraft's trajectory was nearly perfect; only minor midcourse corrections were required to place the craft squarely in the target area, in the Sea of Tranquillity.
Cameras in Ranger VIII were turned on 23 minutes before impact, and the spacecraft transmitted pictures back to earth until it struck the surface and was destroyed. The flight's product would be intensively studied by a panel of noted lunar scientists, among them Gerard P. Kuiper and Ewen A. Whitaker of the University of Arizona and Harold C. Urey of the University of California.
Astronautics and Aeronautics, 1965, pp. 73-74, 84-85.
February 17MSC directed North American to delete the rendezvous radar from Block II CSMs. On those spacecraft North American instead would install LEM rendezvous radar transponders. Grumman, in turn, was ordered to halt its work on the CSM rendezvous radar (both in-house and at RCA) as well as all support efforts. At the same time, however, the company was directed to incorporate a tracking light on the LEM (compatible with the CSM telescope sextant) and to modify the spacecraft's VHF equipment to permit range extraction in the CSM. (See February 8 and March 15.)
Letter, H. P. Yschek, MSC, to NAA, Space and Information Systems Div., "Contract NAS 9-150, CCA to Cover Removal of Rendezvous Radar Installation on CSM (MSN 150-508)," February 16, 1965; letter, Yschek, to NAA, S&ID, "Contract Change Authorization No. 303," February 17, 1965; letter, J. B. Alldredge, MSC, to NAA, S&ID, "Contract Change Authorization No. 303, Revision 1," March 11, 1965; letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Item 3, Contractor Responsibilities, Rendezvous Radar and Transponder," March 8, 1965, with enclosure.
February 17North American proposed an idea for increasing the CM's land landing capability. This could be done, the company asserted, by raising the water impact limits (thus exceeding normal tolerances) and stiffening the shock struts. Presently, the spacecraft was incapable of a land landing within established requirements (i.e., in a 46-km [25-nm] wind). While even approximate figures were not available, the maximum wind velocity in which the CM could land - without exceeding crew tolerances - was probably between 19 and 28 km (10 and 15 nm) per hr. (No precise data on land and water landings would be available until after the drop tests of boilerplate 28 late in the year.)
Personnel of the ASPO Crew Integration Branch, however, were pessimistic about the North American scheme. They doubted that shock attenuation could be readily increased, nor did they see as likely any relaxation of crew tolerances. Further, the probability of a land landing introduced tighter constraints on wind conditions at the launch site. As they viewed it, the only feasible way to improve the spacecraft's ground capability was through some mechanism that would further absorb the landing impact.
Memorandum, Joseph P. Loftus, Jr., MSC, to Chief, Systems Engineering Division, "Command Module land impact capability," February 17, 1965.
February 17ASPO Manager Joseph F. Shea clarified the manned unmanned capabilities required of Block I CSM spacecraft to ensure that end-item specifications appropriately reflect those capabilities.
CSMs 017 and 020 would fly unmanned entry tests on the Saturn V and need not be capable of manned missions. CSMs 012 and 014 were to be delivered to KSC for manned orbital missions on the Saturn IB but must be capable of being modified to fly unmanned missions.
The planning for CSM 012 should be such that the mission type could be selected 5½ months prior to the scheduled launch of the 204 mission, yet not delay the launch.
Memorandum, Shea, MSC, to Chief, Systems Engineering Division, "Block I CSM Mission Capabilities," February 17, 1965.
February 18LEM Test Article 2 was shipped to Marshall Space Flight Center to undergo a series of Saturn booster vibration tests.
"Monthly Progress Report No. 25," LPR-10-41, March 10, 1965, p. 1.
February 18MSC's Crew Systems Division decreed that the extravehicular mobility unit (EMU) would employ a single garment for both thermal and meteoroid protection. By an earlier decision, the penetration probability requirement had been lowered from 0.9999 to 0.999. This change, along with the use of newer, more efficient materials, promised a substantial lightening of the garment (hopefully down to about 7.7 kg [17 lbs], excluding visors, gloves, and boots). The division also deleted the requirement for a separate meteoroid visor, because the thermal and glare visors provided ample protection against meteoroids as well. Tests by Ling-Temco-Vought confirmed the need for thermal protection over the pressure suit during extravehicular transfer by the LEM crewmen.
Memorandum, Robert E. Smylie, MSC, to Chief, Systems Engineering Division, "Extravehicular Mobility Unit (EMU) thermal anti meteoroid protection," February 18, 1965.
February 18-25Because of the CM's recent weight growth, the launch escape system (LES) was incapable of lifting the spacecraft the "specification" distance away from the booster. The performance required of the LES was being studied further; investigators were especially concerned with the heat and blast effects of an exploding booster, and possible deleterious effects upon the parachutes.
MSC, "ASPO Weekly Management Report, February 18-25, 1965."
February 19NASA selected Philco's Aeronutronic Division to design a penetrometer for possible use in the Apollo program. Impacting on the moon, the device would measure the firmness and bearing strength of the surface. Used in conjunction with an orbiting spacecraft, the system could provide scientific information about areas of the moon that were inaccessible by any other means. Langley Research Center would negotiate and manage the contract, estimated to be worth $1 million.
NASA News Release 65-59, "NASA to Negotiate With Philco for Study of Moon Penetrometer," February 19, 1965; Astronautics and Aeronautics, 1965, p. 82.
February 19To eliminate interference between the S-IVB stage and the instrument unit, MSC directed North American to modify the deployment angle of the adapter panels. Originally designed to rotate 170 degrees, the panels should open but 45 degrees (60 degrees during abort), where they were to be secured while the CSM docked with and extracted the LEM.
But at this smaller angle, the panels now blocked the CM's four flush- mounted omnidirectional antennas, used during near-earth phases of the mission. While turning around and docking, the astronauts thus had to communicate with the ground via the steerable high gain antenna. For Block II spacecraft, therefore, MSC concurrently ordered North American to broaden the S-band equipment's capability to permit it to operate within 4,630 km (2,500 nm) of earth.
Letter, H. P. Yschek, MSC, to NAA, Space and Information Systems Division, "Contract Change Authorization No. 304," February 19, 1965; letter, Yschek to NAA, S&ID, "Contract Change Authorization No. 305," February 19, 1965.
February 23NASA awarded a fixed-price contract (worth l.5 million) to IBM to design a backup guidance and navigation computer for the Apollo CM.
MSC, "Quarterly Activity Report for the Office of the Associate Administrator, Manned Space Flight, for the Period Ending April 30, 1965," p. 24.
February 23William F. Rector III, MSC's LEM Project Officer, reported at an ASPO Manager's Staff Meeting that the expected firing date for the heavyweight ascent (HA) rig #3 at WSTF had been slipped from March 18, 1965, until April 13. Grumman personnel at White Sands said the slip was necessary because
February 23-26MSC and North American conducted Part 2 of the mockup review of the CM's forward compartment and lower equipment bay. (Part 1 was accomplished January 14-15. This staged procedure was in line with the contractor's proposal for a progressive review program leading up to the Critical Design Review scheduled for July 19-23.) Except for minor changes, the design was acceptable.
"Apollo Monthly Progress Report," SID 62-300-33, p. 24; MSC, "ASPO Weekly Management Report, February 25-March 4, 1965."
February 24NASA awarded a $2,740,000 fixed-price contract to the Collins Radio Company for S-band telemetry equipment. Collins would install the equipment at three antenna facilities that supported Apollo lunar missions (at Goldstone, Calif.; Canberra, Australia; and Madrid, Spain).
NASA News Release 65-63, "Collins to Make S-Band Systems for Three 85-Foot Apollo Antennas," February 24, 1965; Space Business Daily, February 26, 1965, p. 286.
February 24MSC's Procurement and Contracts Division notified ASPO that John B. Alldredge had been assigned as the Contracting Officer for Contract NAS 9-150 (the North American contract), replacing Henry P. Yschek.
Memorandum, C. L. Taylor, MSC, to Distr., "Notification of new Contracting Officer for C&SM Contract NAS 9-150," sgd. W. R. Kelly, February 24, 1965.
February 25MSC and the David Clark Company reached an agreement on a contract for Apollo Block I space suits. The first suits, expected by July 1, would go to North American for testing.
Memorandum, Matthew I. Radnofsky, MSC, to Gemini and Flight Support Procurement, Attn: Arc F. Lee, "Contract NAS 9-3642, Apollo Block I Suit, David Clark Company," February 25, 1965.
February 25KSC supplemented Chrysler Corporation's contract for support services for the Saturn I and IB launch programs. Effective through June 30, 1968, the agreement would cost NASA $41 million plus an award fee.
Astronautics and Aeronautics, 1965, p. 94.
February 25Using a mockup Apollo CM, MSC Crew Systems Division tested the time in which an astronaut could don and doff the Block I pressure garment assembly while at various stations inside the spacecraft. The two subjects' average donning times were nine min 33 sec and 10 min; mean doffing times were four min five sec and five min 23 sec.
MSC, "ASPO Weekly Management Report, February 25-March 4, 1965."
February 25-March 4To determine thermal and vacuum effects on the CM's parachutes, MSC Structures and Mechanics Division tested nylon samples in a vacuum under varying temperature conditions. After two weeks of exposure to this spacelike environment, the samples exhibited only a 16 percent loss of strength (as against a design allowable of 25 percent).
February 25-March 4DeHavilland completed deployment tests of the CM's pop-up recovery antenna.
February 25-March 4On the basis of in-house tests, Grumman recommended a scheme for exterior lighting on the LEM. The design copied standard aeronautical practice (i.e., red, port; green, starboard; and amber, underside). White lights marked the spacecraft, both fore and aft; to distinguish between the two white lights, the aft one contained a flasher.
Ibid.; "Monthly Progress Report No. 25," LPR-10-41, p. 22.
February 26ASPO Manager Joseph F. Shea named William A. Lee as an assistant program manager. Lee, who previously headed the Operations Planning Division (which had been absorbed into Owen E. Maynard's Systems Engineering Division), now assumed responsibility for Apollo Operations (both the flight-test program and the lunar mission). Lee thus joined Harry L. Reynolds, also an assistant manager, who was assigned to the LEM's development. Deputy Manager Robert O. Piland continued overseeing the CSM's development and, along with Shea, overall program management.
MSC News Release 65- 34, February 26, 1965.
February 26Louis Walter, Goddard Space Flight Center geochemist, reported that his research with tektites indicated the lunar surface may be sandlike. Waiter had discovered the presence of coesite in tektites, believed to be particles of the moon sent into space when meteorites impact the lunar surface. Coesite, also found at known meteorite craters, is a form of silicon dioxide - a major constituent of sand - produced under high pressure. "If we accept the lunar origin of tektites," Walter said, "this would prove or indicate that the parent material on the moon is something like the welded tuft that we find in Yellowstone Park, Iceland, New Zealand, and elsewhere." Welded tuft was said to have some of the qualities of beach sand.
Astronautics and Aeronautics, 1965, p. 96.
During the MonthBecause of a change in the size of the entry corridor, North American technicians sought to determine whether they might relax the requirements for pointing accuracy of the stabilization and control system at transearth injection. They could not. To ensure a delta-V reserve, the accuracy requirement must remain unchanged.
"Apollo Monthly Progress Report," SID 62-300-35, p. 8.
During the MonthGrumman reported three major problems with the LEM: