The Apollo Spacecraft - A Chronology.

Advanced Design, Fabrication, and Testing

March 1965


March 1

ASPO organized a new management group, the Configuration Control Board, to oversee proposals for engineering changes. The board comprised groups representing management, the three Apollo modules, and critical Apollo systems (guidance and navigation, spacecraft checkout equipment, and the extravehicular mobility unit).

MSC, "Apollo Spacecraft Program Office Configuration Management Plan, March 1, 1965," Revision A, March 19, 1965.

LEM descent stage

LEM descent stage.

March 2

MSC decided in favor of an "all-battery" LEM (i.e., batteries rather than fuel cells in both stages of the vehicle) and notified Grumman accordingly. Pratt and Whitney's subcontract for fuel cells would be terminated on April 1; also, Grumman would assume parenthood of GE's contract (originally let by Pratt and Whitney) for the electrical control assembly. MSC ordered an immediate cessation of all other efforts involved in the fuel-celled configuration. During the next several weeks, Grumman issued study contracts to Yardney Electric and Eagle-Picher for cost proposals. On April 1, the spacecraft manufacturer presented its proposal for an all-battery LEM; MSC's concurrence followed two weeks later.

A portable life support system (PLSS) battery charger would no longer be required, but three additional nonrechargeable PLSSs would be carried to provide for extravehicular activities. This change would now require a total of six nonrechargeable batteries.

On this same date, MSC ordered Grumman to end its work on a supercritical helium system for the LEM's ascent stage, and to incorporate an ambient mode for pressurization. All work on a supercritical system for the stage should be halted. However, Grumman should maintain the supercritical approach for the descent stage, while continuing parallel development on the ambient system. To permit the incorporation of either approach into the final design of the descent stage, components must be interchangeable.

Letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Implementation of Electrical Power Subsystem and Supercritical Helium Pressurization Configuration Changes," March 2, 1965; memorandum, Owen E. Maynard, MSC, to Chief, Instrumentation and Electronic Systems Division, "LEM Power generation system," March 15, 1965; GAEC, "Implementation of LEM All-Battery Configuration," April 1, 1965; letter, Rector to GAEC, Mullaney, "Contract NAS 9-1100, Implementation of All-Battery Configuration," April 15, 1965; "Monthly Progress Report No. 25," LPR-10-41, pp. 1, 20; GAEC, "Monthly Progress Report No. 26, "LPR-10-42, April 10, 1965, pp. 1, 31; TWX, James L. Neal, MSC, to GAEC, Attn: R. S. Mullaney, March 11, 1965.

March 2

MSC Structures and Mechanics Division presented their findings on the possibility of qualifying the spacecraft's thermal protection in a single mission. While one flight was adequate to prove the ablator's performance, the division asserted, it would not satisfy the requirements as defined in the specification.

Memorandum, Joseph N. Kotanchik, MSC, to Chief, Systems Engineering Division, "Adequacy of the SA 501 Mission to Qualify the Apollo Thermal Protection System," March 3, 1965, with enclosures.

March 3

NASA and General Motors' AC Spark Plug Division signed the definitive contract (cost-plus-incentive-fee type) for primary guidance and navigation systems for the Apollo spacecraft (both CMs and LEMs). The agreement, extending through December 1969, covered manufacturing and testing of the systems.

NASA News Release 65-33, March 3, 1965.

March 3

To prevent radiator freezing - and consequent performance degradation - in the Block I environmental control system, MSC ordered North American to supplement the system's coolant. Forty-five kg (100 lbs) of water would be stored in the SMs of airframes 012 and 014.

Letter, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division, "Contract Change Authorization No. 309," March 3, 1965.

March 4

North American gave boilerplate 28 its third water drop test. Upon impact, the spacecraft again suffered some structural damage to the heatshield and the core, though much less than it had experienced on its initial drop. Conditions in this test were at least as severe as in previous ones, yet the vehicle remained watertight.

MSC, "ASPO Weekly Management Report, March 4-11, 1965."

March 5

Newton W. Cunningham, NASA's Ranger Program Manager, notified Apollo Program Manager Samuel C. Phillips that the Ranger investigators and Jet Propulsion Laboratory Ranger Project Office had submitted their unanimous choice of targets for the Ranger IX mission. The first two days of the launch windows were omitted from the plan; Day III: Crater Alphonsus; Day IV: Crater Copernicus; Day V: Crater Kepler; Day VI: Crater Aristarchus; Day VII: near Crater Grimaldi.

NASA's Office of Manned Space Flight agreed with Days IV-VII, but recommended a smooth highland area for Day I, a highland basin area for Day II, and the Flammarion highland basin for Day III.

Memorandum, Newton W. Cunningham, NASA, to Gen. Samuel C. Phillips, "Ranger 9 Target Selection," March 5, 1965; "Ranger D Target Selection," March 8, 1965.

March 5

Researchers at Ames Research Center began testing the stability of the Block II CM and escape tower (with canards) in the Center's wind tunnel. Tests would be conducted on the CM itself and while mated with the tower.

NAA, "Apollo Monthly Progress Report," SID 62-300-36, May 1, 1965, p. 3.

March 8

Preliminary investigation by Grumman indicated that, with an all-battery LEM, passive thermal control of the spacecraft was doubtful. (And this analysis did not include the scientific experiments package, which, with its radioisotope generator, only increased the problem. Grumman and MSC Structures and Mechanics Division engineers were investigating alternate locations for the batteries and modifications to the surface coatings of the spacecraft as possible solutions.

Memorandum, Lee N. McMillion, MSC, to Owen E. Maynard, "Radioisotope power generator," March 5, 1965.

March 8

Northrop-Ventura began qualification testing of the CM's earth landing sequence controller.

MSC, "ASPO Weekly Management Report, March 4-11, 1965."

March 8

Missiles and Rockets reported a statement by Joseph F. Shea, ASPO manager, that MSC had no serious weight problems with the Apollo spacecraft. The current weight, he said, was 454 kg (1,000 lbs) under the 40,823 kg (90,000 lb) goal. Moreover, the increased payload of the Saturn V to 43,091 kg (95,000 lbs) permitted further increases. Shea admitted, however, that the LEM was growing; recent decisions in favor of safety and redundancy could raise the module's weight from 13,381 kg to 14,575 kg (29,500 lbs to 32,000 lbs).

Astronautics and Aeronautics, 1965, p. 113.

March 9

Avco found that cracking of the ablator during cure was caused by incomplete filling, leaving small voids in the material. The company ordered several changes in the manufacturing process: a different shape for the tip of the "filling gun" to facilitate filling those cells that were slightly distorted; manual rather than automatic retraction of the gun; and x-raying of the ablator prior to curing. Using these new methods, Avco repaired the aft heatshield and toroidal corner of airframe 006, which was then re-cured. No cracking was visible. The crew compartment heatshield for airframe 009 came through its cure equally well. Voids in the ablator had been reduced to about two percent. "It appears," Structures and Mechanics Division reported, "that the problem of cracking . . . has been solved by better manufacturing."

MSC, "ASPO Weekly Management Report, March 4-11, 1965"; MSC, "ASPO Weekly Management Report, March 11-18, 1965"; memorandum, C. H. Perrine, MSC, to B. Erb and Leo Chauvin, "Attached draft of letter to NASA Headquarters on use of Block I Command Modules for Block II Heat Shield Qualification," March 9, 1965, with attachment.

March 9

Initial flights of the LLRV interested MSC's Guidance and Control Division because they represented first flight tests of a vehicle with control characteristics similar to the LEM. The Division recommended the following specific items for inclusion in the LLRV flight test program:

  • The handling qualities of the LEM attitude control system should be verified using the control powers available to the pilot during the landing maneuver. The attitude controller used in these tests should be a three-axis LEM rotational controller.
  • The ability of pilots to manually zero the horizontal velocities at altitudes of 30.48 m (100 ft) or less should be investigated. The view afforded the pilot during this procedure should be equivalent to the view available to the pilot in the actual LEM.
  • The LEM descent engine throttle control should be investigated to determine proper relationship between control and thrust output for the landing maneuver.
  • Data related to attitude and attitude rates encountered in landing approach maneuvers were desirable to verify LEM control system design limits.
  • Adequacy of LEM flight instrument displays used for the landing maneuver should be determined.
Guidance and Control Division would provide information as to control system characteristics and desired trajectory characteristics. D. C. Cheatham, a member of the Lunar Lander Research Vehicle Coordination Panel, would coordinate such support.

Memorandum, Robert C. Duncan, MSC, to Chief, Flight Crew Support Division, "Recommended items for LLRV Flight Test Program," March 9, 1965.

March 10

NASA announced that it had awarded a$3,713,400 contract to Raytheon Company for digital systems for the Apollo program. The equipment, which would be installed at control and tracking stations, would display information telemetered from the spacecraft, and thus would support mission decisions on the ground.

NASA News Release 65-79, "NASA Names Raytheon for Apollo Digital Display Equipment," March 10, 1965.

March 11

MSC directed North American to incorporate the capability for storing a kit-type mapping and survey system into the basic Block II configuration. The actual hardware, which would be installed in the equipment bay of certain SMs (designated by MSC), would weigh up to 680 kg (1,500 lbs).

Letter, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division, "Contract Change Authorization No. 317," March 11, 1965.

March 11

MSC notified Grumman that a device to recharge the portable life support system's (PLSS) batteries was no longer required in the LEM. Instead, three additional batteries would be stored in the spacecraft (bringing the total number of PLSS batteries to six).

TWX, James L. Neal, MSC, to GAEC, Attn: R. S. Mullaney, March 11, 1965.

March 11

MSC's Structures and Mechanics Division was conducting studies of lunar landing conditions. In one study, mathematical data concerning the lunar surface, LEM descent velocity, and physical properties of LEM landing gear and engine skirt were compiled. A computer was programmed with these data, producing images on a video screen, allowing engineers to review hypothetical landings in slow motion.

In another study, a one-sixth scale model of the LEM landing gear was dropped from several feet to a platform which could be adjusted to different slopes. Impact data, gross stability, acceleration, and stroke of the landing gear were recorded. Although the platform landing surface could not duplicate the lunar surface as well as the computer, the drop could verify data developed in the computer program. The results of these studies would aid in establishing ground rules for lunar landings.

MSC News Release 65-42, March 11, 1965.

March 11-18

MSC concurred in North American's recommendation that the 27½ degrees hang angle during parachute descent be retained. (Tests with one-tenth scale models of the CM indicated that, at the higher impact angles, excessive pressures would be exerted on the sidewalls of the vehicle.) Provisions for a "dual hang angle" were still in effect for Block I spacecraft up to airframe 017. Beginning with that number, the face sheets on the aft heatshield would be modified to conform to the 27½ degree impact angle.

"ASPO Weekly Management Report, March 11-18, 1965."

March 11-18

Crew Systems Division (CSD) engineers were studying several items that, though intended specifically for the Gemini program, were applicable to Apollo as well:

  • During recent tests of the urine nozzle by McDonnell, microorganisms had been found in the sample. This indicated that explosive decompression into very low temperatures had failed to sterilize the urine. To determine possible shifts in the microbial pattern, CSD was examining samples both before and after dumping.
  • Division researchers completed microbiological examinations of Gemini food bags. They found that, even though disinfectant tablets were not completely effective, storage of the containers for periods up to two weeks was nonetheless feasible. (These studies thus reinforced earlier findings of bacterial growth in the bags.)
CSD engineers also evaluated the Gemini-type water dispenser and found it suitable for the Apollo CM as well.


March 11-18

During the flight of boilerplate (BP) 23, the Little Joe II's control system had coupled with the first lateral bending mode of the vehicle. To ensure against any recurrence of this problem on the forthcoming flight of BP-22, MSC asked North American to submit their latest figures on the stiffness of the spacecraft and its escape tower. These data would be used to compute the first bending mode of BP-22 and its launch vehicle.


March 12

During a pad abort, propellants from the CM's reaction control system (RCS) would be dumped overboard. Structures and Mechanics Division (SMD) therefore established a test program to evaluate possible deleterious effects on the strength of the earth landing system's nylon components. SMD engineers would expose test specimens to RCS fuel (monomethyl hydrazine) and oxidizer (nitrogen tetroxide). This testing series would encompass a number of variables: the length of exposure; the time period between that exposure and the strength test; the concentration of propellant; and the rate and direction of the air flow. Testing was completed near the end of the month. SMD reported that "no significant degradation was produced by any of the test exposure conditions."

Memorandum, Robert B. West, MSC, to Paul E. Fitzgerald, "Preliminary report on minimum ELS requirements in the pad abort mode," March 12, 1965; "ASPO Weekly Management Report, March 11-18, 1965"; MSC, "ASPO Weekly Management Report, March 18-25, 1965."

March 15

MSC defined the functional and design requirements for the tracking light on the LEM:

  • The light must be compatible for use with CSM scan telescope sextant optics in visual mode during darkside lunar and earth operations.
  • The light must provide range capability of 324.1 km (175 nm) for darkside lunar operations when viewed with the CSM sextant.
  • The probability of detection within three-minute search time at maximum range when viewed with CSM sextant must exceed 99 percent for worst lunar background.
  • The light must flash at the optimum rate for ease of detection and tracking (60 flashes per minute ±5 fpm).
  • Brightness attenuation must be available for terminal phase operation and for minimizing spacecraft electrical energy drain.
  • The light must be capable of inflight operation for continuous periods of one hour duration over four cycles.
  • The light must have a total operating life of 30 hours at rated output with a shelf life of two years.
  • The light was not required to be maintainable at the component level.
  • The total system weight including cooling and electromagnetic interference shielding, if required, should not exceed 5.44 kg (12 lbs).
Letter, Joseph F. Shea, MSC, to GAEC, Attn: R. S. Mullaney, "Functional and design requirements for LEM tracking light," March 15, 1965.

March 15

In November 1964, MSC asked Grumman to conduct a study on the feasibility of carrying a radioisotope power supply as part of the LEM's scientific equipment. The subsequent decision to use batteries in the LEM power system caused an additional heat load in the descent stage. Therefore, MSC requested the contractor to continue the study using the following ground rules: consider the radioisotope power supply a requirement for the purpose of preliminary design efforts on descent stage configuration; determine impact of the radioisotope power supply - in particular its effect on passive thermal control of the descent stage; and specify which characteristics would be acceptable if any existing characteristics of the radioisotope power supply had an adverse effect. The radioisotope power was used only to supply power for the descent stage.

TWX, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, subject: "Radioisotope Power Supply for Lunar Scientific Experiments," March 15, 1965.

March 15

An evaluation was made of the feasibility of utilizing a probe-actuated descent engine cutoff light during the LEM lunar touchdown maneuver. The purpose of the light, to be actuated by a probe extending 0.9 m (3 ft) beyond the landing gear pads, was to provide an engine cutoff signal for display to the pilot. Results of the study indicated at least 20 percent of the pilots failed to have the descent engine cut off at the time of lunar touchdown. The high percentage of engine-on landings was attributed to

  1. poor location of the cutoff switch,
  2. long reaction time (0.7 sec) of the pilot to a discrete stimulus (a light), and
  3. the particular value of a descent rate selected for final letdown (4 ft per sec).
It was concluded that a 0.9-m (3-ft) probe would be adequate to ensure pilot cutoff of the descent engine before touchdown provided the pilot reaction time could be reduced to 0.4 sec or less by improving the location of the cutoff switch.

Richard Reid, MSC, MSC-IN-65-EG-10, "Simulation and Evaluation of Landing Gear Probe for Sensing Engine Cutoff Altitude During Lunar Landing," March 15, 1965.

March 15-17

North American conducted acoustic tests on the spacecraft's interior, using boilerplate (BP) 14. Noise levels generated by the spacecraft's equipment exceeded specifications. Prime culprits appeared to be the suit compressor and the cabin fans. North American engineers asserted, however, that the test vehicle itself, because of its sheet metal construction, compounded the problem. These tests with BP-14, they affirmed, were not representative of conditions in flight hardware. Data on communications inside the spacecraft were inconclusive and required further analysis, but the warning alarm was sufficiently loud to be heard by the crewmen.

"ASPO Weekly Management Report, March 18-25, 1965."

March 16

MSC estimated the number of navigational sightings that Apollo crewmen would have to make during a lunar landing mission:

  • Translunar coast
    1. four maneuvers to align the inertial measurement unit (IMU)
    2. 20 navigational sightings requiring 10 maneuvers
  • Transearth coast
    1. four maneuvers for IMU alignment
    2. 50 sightings, 25 maneuvers
  • Lunar orbit
    1. 10 maneuvers for IMU alignment
    2. 24 sightings, 24 maneuvers.
[The Manned Space Flight Network was the primary source for navigational data during the coasting phases of the mission; and although the network could supply adequate data during the circumlunar phase as well, onboard capability must be maintained.]

Letter, C. L. Taylor, MSC, to NAA, Space and Information Systems Division, Attn: J. C. Cozad, "Contract NAS 9-150, Navigational Sightings Required for the Lunar Landing Mission," March 16, 1965.

March 16

Because the adapter panels, when deployed to 45 degrees, would block the command link with the LEM, a command antenna system on the adapter was mandatory. MSC therefore directed North American to provide such a device on the adapters for spacecraft 014, 101, and 102. This would permit command acquisition of the LEM in the interval between panel deployment and the spacecraft's clearing the adapter.

Letter, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division, "Contract Change Authorization No. 322," March 16, 1965.

March 16

MSC directed North American to include nine scientific experiments on SA 204/Airframe 012: cardiovascular reflex conditioning, bone demineralization, vestibular effects, exercise ergometer, inflight cardiac output, inflight vector cardiogram, measurement of metabolic rate during flight, inflight pulmonary functions, and synoptic terrain photography. On June 25, the last five experiments were deleted and a cytogenic blood studies experiment was added.

Letter, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division (S&ID), "Contract Change Authorization No. 323," March 16, 1965; letter, Alldredge to S&ID, "Contract Change Authorization No. 323, Revision 1," June 25, 1965.

March 16

MSC eliminated the requirement for relaying, via the LEM/CSM VHF link, transmissions from a moon-exploring astronaut to the earth. This change allowed the 279.0 megacycle (Mc) transmitters in both vehicles to be eliminated; cleared the way for a common VHF configuration; and permitted duplex voice communications between astronaut and spacecraft. For communicating with the LEM, MSC directed North American to provide a 259.7 Mc transmitter in the CSM.

Letter, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division, "Contract Change Authorization No. 320," March 16, 1965.

March 16

ASPO proposed deletion of a liftoff light in the Block II CM. The Block I design provided a redundant panel light which came ON at liftoff as a part of the emergency detection system (EDS). This light gave a cue to the pilot to verify enabling of the EDS automatic abort, for which manual backup was provided. The Block II CM would incorporate improved EDS circuitry without manual backup. Deletion of the liftoff light in the CM was proposed to save weight, power, space, and reliability, and to eliminate a crew distraction during the boost phase of flight.

Memorandum, Joseph F. Shea, MSC, to Assistant Directors for Flight Crew Operations and Flight Operations, "Deletion of Lift-off Light, Apollo Command Module," signed William A. Lee, March 16, 1965.

March 16-April 15

North American dropped boilerplate 1 twice to measure the maximum pressures the CM would generate during a high-angle water impact. These figures agreed quite well with those obtained from similar tests with a one-tenth scale model of the spacecraft, and supported data from the model on side wall and tunnel pressures.

"Apollo Monthly Progress Report," SID 62-300-36, p.3.

March 17

After extensive analysis, Crew Systems Division recommended that the "shirtsleeve" environment be kept in the CM. Such a design was simpler and more reliable, and promised much greater personal comfort than wearing the space suit during the entire mission.

Memorandum, Maxime A. Faget, MSC, to Manager, ASPO, "Crew Systems Division recommendation on establishment of suit wear criterion," March 17, 1965.

March 18

Russia launched Voskhod II from the Baikonur Cosmodrome in Kazakhstan, piloted by Colonel Pavel Belyayev and Lt. Colonel Aleksey Leonov into an orbit 497 by 174 km (309 by 108 mi) high. During Voskhod II's second orbit, Leonov stepped from the vehicle and performed mankind's first "walk in space." After 10 min of extravehicular activity, he returned safely to the spacecraft (apparently leaving and entering through an airlock). On the following day, the two cosmonauts landed near Perm, Russia, after 17 orbits and 26 hours of flight.

Astronautics and Aeronautics, 1965, pp. 131-132, 136, 157.

March 18

Because of continuing developmental problems, Hamilton Standard chose B. F. Goodrich to replace International Latex as subcontractor for the garment portion of the Apollo space suit.

Letter, Joseph F. Shea, MSC, to NASA Headquarters, Attn: George E. Mueller, "Extravehicular Mobility Unit subcontractor change," March 18, 1965.

March 18

Grumman officials presented their findings on supercritical versus gaseous oxygen storage systems for the LEM [supercritical: state of homogeneous mixture at a certain pressure and temperature, being neither gas nor liquid]. After studying factors of weight, reliability, and thermal control, as well as cost and schedule impacts, they recommended gaseous tanks in the ascent stage and a supercritical tank in the descent stage. They stressed that this configuration would be about 35.66 kg (117 lbs) lighter than an all-gaseous one. Though these spokesmen denied any schedule impact, they estimated that this approach would cost about 2 million more than the all-gaseous mode. MSC was reviewing Grumman's proposal.

During the latter part of the month, Crew Systems Division (CSD) engineers also looked into the several approaches. In contrast to Grumman, CSD calculated that, at most, an all-gaseous system would be but 4.08 kg (9 lbs) heavier than a supercritical one. CSD nonetheless recommended the former. It was felt that the heightened reliability, improved schedules, and "substantial" cost savings that accompanied the all-gaseous approach offset its slim weight disadvantage.

During late April, MSC ordered Grumman to adopt CSD's approach (gaseous systems in both stages of the vehicle). [Another factor involved in this decision was the lessened oxygen requirement that followed substitution of batteries for fuel cells in the LEM. See March 2.]

GAEC, "Monthly Progress Report No. 27," LPR-10-43, May 10, 1965, p. 17; MSC, "ASPO Weekly Management Report, March 18-25, 1965"; "ASPO Weekly Management Report, March 25-April 1, 1965"; "ASPO Weekly Management Report, April 22-29, 1965."

March 18

Lawrence B. Hall, Special Assistant for Planetary Quarantine, Bioscience Programs, Office of Space Science and Applications, NASA Headquarters, listed preliminary requirements for space in the Lunar Sample Receiving Station as recommended by the Communicable Disease Center of the Public Health Service. The estimates were based on CDC experience involving the design, construction, and operation of similar biological facilities and called for net space amounting to 7,201 sq m (77,492 sq ft) for laboratories, scientific support service facilities, offices and other areas, and did not reflect requirements of the U.S. Department of Agriculture or experimenters who could justify their work being done under quarantine conditions. Hall noted that Dr. Randolph Lovelace and the Chief of CDC were in agreement that the facility should be isolated, certainly not in or near a metropolitan area, and that an island would be favored.

Memorandum for Record, Lawrence B. Hall, "Primary barrier for lunar quarantine," March 18, 1965.

March 18-25

Structures and Mechanics Division engineers were studying several schemes for achieving the optimum weight of Block II CMs without compromising landing reliability: reducing velocity by retrorockets or "explosions" in the parachutes; controlling roll attitude to 0 degrees at impact through a "rotatable pot" structure; changing landing medium (i.e., shape hole in water and/or aeration of the water).

MSC, "ASPO Weekly Management Report, March 18-25, 1965."

March 18-25

Crew Systems Division (CSD) engineers, continuing their evaluation of liquid-cooled garments (LCG), tested Hamilton Standard's newest version (the LCG-8). The manufacturer had modified placement of the tubes and had used a stretchable, more closely knit fabric. CSD found this style an improvement over its predecessor (the LCG-3): it was more efficient, more comfortable, and easier to don and doff. CSD officials accordingly froze the configuration of the garment around this latest model. Further design work would be minimal (chiefly interface modifications and improvements in fabrication techniques).


March 18-25

The Atomic Energy Commission evaluated proposals by Radio Corporation of America and General Electric (GE) for an isotope generator for the Surveyor lunar roving vehicle, and assigned follow-on work to the latter firm. GE's concept, it was felt, was compatible with the possible requirement that the fuel source might have to be carried separately aboard the LEM. MSC's Propulsion and Power Division reported that the generator's "prospects . . . look[ed] very promising."


March 19

Bell Aerosystems Company reported that a study had been made to determine if it were practical to significantly increase simulation time without major changes to the Lunar Landing Research Vehicle (LLRV). This study had been made after MSC personnel had expressed an interest in increased simulation time for a trainer version of the LLRV. The current LLRV was capable of about 10 minutes of flight time and two minutes of lunar simulation with the lift rockets providing one-sixth of the lift. It was concluded that lunar simulation time approaching seven minutes could be obtained by doubling the 272-kg (600-lb) peroxide load and employing the jet engine to simulate one-half of the rocket lift needed for simulation.

A major limiting factor, however, was the normal weather conditions at Houston, where such a training vehicle would be located. A study showed that in order to use a maximum peroxide load of 544 kg (1,200 lbs), the temperature could not exceed 313K (40 degrees F); and at 332K (59 degrees F) the maximum load must be limited to 465 kg (1,025 lbs) of peroxide. On the basis of existing weather records it was determined there would be enough days on which flights could be made in Houston on the basis of 544 kg (1,200 lbs) peroxide at 313K (40 degrees F), 465 kg (1,025 lbs) at 332K (59 degrees F), and 354 kg (775 lbs) at 353K (80 degrees F) to make provisions for such loads.

Letter, John Ryken, Bell Aerosystems Company, to Ronald Decrevel, "Preliminary Study of Methods of Increasing LLRV Lunar Simulation Time," March 19, 1965; letter, Ryken to Decrevel, "Effect of Houston Temperatures on Allowable LLRV Weight and Flight Time," March 23, 1965.

March 21

NASA launched Ranger IX, last of the series, from Cape Kennedy aboard an Atlas-Agena vehicle. The target was Alphonsus, a large crater about 12 degrees south of the lunar equator. The probe was timed to arrive when lighting conditions would be at their best. The initial trajectory was highly accurate; uncorrected, the craft would have landed only 400 miles north of Alphonsus. On March 23, a midcourse correction increased Ranger IX's speed and placed it on a near-perfect trajectory: the spacecraft impacted the following day only four miles from the original aiming point.

From 2,092 km (1,300 mi) out until it was destroyed on impact, Ranger IX's six television cameras took 5,814 pictures of the lunar surface. These pictures were received at Jet Propulsion Laboratory's Goldstone, Calif., Tracking Laboratory, where they were recorded on tape and film for detailed analysis. They also were released to the nation's three major television networks in "real time," so millions of Americans followed the spacecraft's descent. The pictures showed the rim and floor of the crater in fine detail: in those just prior to impact, objects less than a foot in size were discernible.

A panel of scientists presented some preliminary conclusions from Ranger IX at a press conference that same afternoon. Crater rims and ridges inside the walls, they believed, were harder and smoother than the moon's dusty plains, and therefore were considered likely sites for future manned landings. Generally, the panel was dubious about landing on crater floors however. Apparently, the floors were solidified volcanic material incapable of supporting a spacecraft. Investigators believed several types of craters were seen that were of nonmeteoric origin. These findings reinforced arguments that the moon at one time had experienced volcanic activity.

Astronautics and Aeronautics, 1965, pp. 140, 142, 143, 146, 148-149; NASA News Release 65-25, "NASA Readies Two Ranger Spacecraft for Moon Missions," February 4, 1965; NASA News Release 65-96, "Ranger IX to Send World's First Live Moon Photos," March 23, 1965.

March 22

Glynn S. Lunney was named by MSC Director Robert R. Gilruth as Assistant Flight Director for Apollo missions 201 and 202. Lunney would continue to serve as Chief of the Flight Dynamics Branch, Flight Control Division, and as MSC Range Safety Coordinator with the U.S. Air Force Eastern Test Range.

MSC Announcement 65-33, "Appointment of Assistant Flight Director for Apollo 201 and 202 Missions," March 22, 1965.

March 22

The change from LEM fuel cells to batteries eliminated the need for a hard-line interstage umbilical for that system and the effort on a cryogenic umbilical disconnect was canceled. The entire LEM pyrotechnic effort was redefined during the program review and levels of effort and purchased parts cost were agreed upon.

MSC, "ASPO Weekly Management Report, March 18-25, 1965."

March 22

Jet Propulsion Laboratory scientists W. L. Sjogren and D. W. Trask reported that as a result of Ranger VI and Ranger VII tracking data, Deep Space Instrumentation Facility station locations could be determined to within 10 m (10.9 yds) in the radial direction normal to the earth's spin axis. Differences in the longitude between stations could be calculated to within 20 m (21.9 yds). The moon's radius had been found to be 3 km (l.86 mi) less than was thought, and knowledge of its mass had been improved by an order of magnitude.

Astronautics and Aeronautics, 1965, p. 160.

March 22

ASPO summarized their requirements for entry monitoring and backup reentry range control:

  • The flight crew would monitor the entry to detect a skip or excessive "g" trajectory early enough to allow manual takeover and safe reentry.
  • The entry corridor should be verified and indications of too steep or shallow an entry displayed to the crew.
  • The spacecraft guidance and control systems should provide manual range control capability after failures in the primary guidance and navigation system (PGNS) prior to reentry, and after discrete or catastrophic failures in the PGNS during reentry.
Memorandum, Joseph F. Shea, MSC, to Chief, Guidance and Control Division, "Requirements for Command Module entry monitoring and backup reentry ranging capability," March 22, 1965.

March 22

MSC ordered Grumman to halt development of linear-shaped charge cutters for the LEM's interstage umbilical separation system, and to concentrate instead on redundant explosive-driven guillotines. By eliminating this parallel approach, and by capitalizing on technology already worked out by North American on the CSM umbilical cutter, this decision promised to simplify hardware development and testing. Further, it promised to effect significant schedule improvements and reductions in cost.

Memorandum, W. F. Rector III, MSC, to Contracting Officer, LEM, "Request for PCCP-MDF Driven Guillotine," March 22, 1965.

March 23

A two-stage Titan II rocket boosted Gemini III and its crew, astronauts Virgil I. Grissom and John W. Young, into an elliptical orbit about the earth. After three orbits, the pair manually landed their spacecraft in the Atlantic Ocean, thus performing the first controlled reentry. Unfortunately, they landed much farther from the landing zone than anticipated, about 97 km (60 miles) from the aircraft carrier U.S.S. Intrepid. But otherwise the mission was highly successful. Gemini III, America's first two-manned space mission, also was the first manned vehicle that was maneuverable. Grissom used the vehicle's maneuvering rockets to effect orbital and plane changes.

NASA News Release 65-81,"NASA Schedules First Manned Gemini Flight from Cape Kennedy," March 17, 1965; James M. Grimwood and Barton C. Hacker, with Peter J. Vorzimmer, Project Gemini Technology and Operations: A Chronology (NASA SP-4002, 1969), pp. 189-191; Astronautics and Aeronautics, 1965, pp. 145-46; "MSC Fact Sheet 291-A, Gemini 3 Flight" [Ivan D. Ertel], April 1965.

March 23-24

Part I of the Critical Design Review of the crew compartment and the docking system in the Block II CM was held at North American. Systems Engineering (SED) and Structures and Mechanics (SMD) divisions, respectively, evaluated the two areas.

  • Crew compartment:
    1. The restraint harness, acceptable in the Block I vehicle, interfered with attachments for the suit umbilicals. These attachments were critical for suit ventilation and mobility; the harness location was likewise critical for crew impact tolerances. Evaluation of alternate locations for the harness and umbilical fittings - or both - awaited the availability of a couch mockup. Manned sled tests might be needed to verify any harness changes.
    2. Restraints at the sleep station must be redesigned. At present, they did not allow sufficient room for a crewman in his pressure suit.
    3. To save weight, North American planned to strap crew equipment to shelves and bulkheads (rather than stowing such gear in compartments, as was done on the Block I vehicle).
    4. Most serious, in an earth landing, when the attenuator struts compressed, the couches would strike a portable life support system (PLSS). "No analysis has been made," SED reported, "to show that this is acceptable." For in such an occurrence, the crew could be injured or killed, the oxygen tank in the PLSS (under about 409 kg [900 lbs] of pressure) could explode, and the aft bulkhead might be ruptured. North American was scheduled to report on this problem on April 27.
  • Docking system:
    1. SMD approved the probe and drogue concept, but recommended that fittings be standardized throughout (so that only one tool was needed).
    2. The division also approved North American's design for the outer side hatch (i.e., limiting its deployment to 90 degrees), pending MSC's final word on deployment requirements.
    3. The division recommended that the forward hatch mechanism be simplified. (North American warned of schedule delays.)
MSC, "ASPO Weekly Management Report, March 18-25, 1965"; MSC, "ASPO Weekly Management Report, March 25-April 1, 1965"; letter, H. G. Osbon, NAA, to NASA MSC, Attn: C. L. Taylor, "Contract NAS 9-150, R&D for Apollo Spacecraft Minutes of Critical Design Review No. 2, Phase I conducted on 23- 24 March, 1965," June 15, 1965.

March 24

Grumman ordered Space Technology Laboratories to increase the lifetime of the thrust chamber in the LEM's descent engine. This required substantial redesigning and was expected to delay the engine's qualification date about seven months.

MSC, "ASPO Weekly Management Report, April 1-8, 1965."

March 24

ASPO requested the Structures and Mechanics Division (SMD) to study the problem of corrosion in the coolant loops of the CM's environmental control system, and to search for effective inhibitors. Current efforts at North American to lessen corrosion included improved hardware and operating procedures, but stopped short of extensive redesigning; and it would be some time before conclusive results could be expected. Early in May, Owen E. Maynard, chief of the Systems Engineering Division, directed SMD immediately to begin its search for inhibitors. If by July 1966 the corrosion problem remained unresolved, SMD could thus recommend stopgap measures for the early spacecraft.

Memorandum, Joseph N. Kotanchik, MSC, to Chief, Systems Engineering Division, "Water/glycol corrosion," March 24, 1965, with enclosure: "Detailed Plan of Investigation on Corrosion Effects of Water/ Glycol Mixtures on Spacecraft Radiators"; memorandum, Owen E. Maynard, MSC, to Chief, Structures and Mechanics Division, "Water/ Glycol Corrosion," May 4, 1965.

March 24

MSC contacted Grumman with reference to the LEM ascent engine environmental tests at Arnold Engineering Development Center (AEDC), scheduled for cell occupancy there from May 1, 1965, until September 1, 1965. It was MSC's understanding that the tests might begin without a baffled injector. It was pointed out, however, that the first test was expected to begin July 1, and since the recent baffle injector design selection had been made, time remained for the fabrication of the injector, checkout of the unit, and shipment to AEDC for use in the first test.

Since the baffled injector represented the final hardware configuration, it was highly desirable to use the design for these tests. MSC requested that availability of the injector constrain the tests and that Grumman take necessary action to ensure compliance.

TWX, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, March 24, 1965.

March 24

ASPO Manager Joseph F. Shea said that the first major test of an Apollo spacecraft AFRM 009 tended to pace the CSM program and therefore had taken on a special program significance. Reflecting this significance, both MSC and North American had applied specific additional senior management and project engineering effort to that spacecraft. In the fall of 1965, Robert O. Piland, ASPO Deputy Manager, was assigned to give priority to AFRM 009 to complement and support the normal ASPO project engineering activities. North American simultaneously gave a special assignment regarding 009 to Assistant Program Manager Charles Feltz.

Recently North American had assigned a Chief Project Engineer to a full-time assignment on 009. ASPO's current management and project engineering plan for the spacecraft was: Piland would continue to give priority attention to 009, in addition to his normal duties, and would deal directly with Feltz. The ASPO Chief Project Engineer Rolf W. Lanzkron would be responsible for all ASPO project engineering activities for all spacecraft to be launched at KSC. He would give priority attention to all Block I spacecraft, ensuring schedules through adequate planning, timely decisions, and rapid referral of problems to the Deputy Manager where appropriate. Lanzkron would coordinate with North American's Chief Project Engineer, Ray Pyle, on matters pertaining to 009. Lanzkron would be supported in the Block I project engineering effort by a group headed by William Petynia.

Memorandum, Joseph F. Shea, MSC, to Distribution, "MSC Management and Project Engineering for AFRM 009," March 24, 1965.

March 25-April 1

After further design studies following the M-5 mockup review (October 5-8, 1964), Grumman reconfigured the boarding ladder on the forward gear leg of the LEM. The structure was flattened, to fit closer to the strut. Two stirrup-type steps were being added to ease stepping from the top rung to the platform or "porch" in front of the hatch.

"ASPO Weekly Management Report, March 25-April 1, 1965"; letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Line Item 4-Lunar Excursion Module, M-5 Review, Chits 1-4 and 1-13," April 30, 1965.

March 25-April 1

North American completed negotiations with Ling-Temco-Vought for design support on the environmental control radiators for Block II CSMs.

"Apollo Monthly Progress Report," SID 62-300-36, p. 8; "ASPO Weekly Management Report, March 25-April 1, 1965."

March 25-April 1

Crew Systems Division confirmed the feasibility of commonality of personal communications equipment for the entire Apollo program.

"ASPO Weekly Management Report, March 25-April 1, 1965"; memorandum, Richard S. Johnston, MSC, to Chief, Systems Engineering Division, Attn: R. Williams, "Apollo space suit communications program definition," April 5, 1965.

March 26

North American began a series of water impact tests with boilerplate 1 to obtain pressure data on the upper portions of the CM. Data on the side walls and tunnel agreed fairly well with those obtained from 1/10 scale model drops; this was not the case with pressures on the top deck, however.

"Apollo Monthly Progress Report," SID 62-300-36, p. 3.

March 27

Test Series I on spacecraft 001 was completed at WSTF Propulsion Systems Development Facility. Vehicle and facility updating in progress consisted of activating the gimbal subsystem and installing a baffled injector and pneumatic engine propellant valve. The individual test operations were conducted satisfactorily, and data indicated that all subsystems operated normally. Total engine firing time was 765 seconds.

"Apollo Monthly Progress Report," SID 62-300-36, pp. 13, 18; memorandum, Spacecraft 001 Project Engineer, to Distribution, "Review of S/C 001 and TF-2 Test Results," April 19, 1965.

March 29

MSC decided upon a grid-type landing point designator for the LEM. Grumman would cooperate in the final design and would manufacture the device; MIT would ensure that the spacecraft's guidance equipment could accept data from the designator and thus change the landing point.

Letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Item 3; LEM Landing Point Designator," March 29, 1965.

March 29

William F. Rector, the LEM Project Officer in ASPO, replied to Grumman's weight reduction study (submitted to MSC on December 15, 1964). Rector approved a number of the manufacturer's suggestions:

  • Delete circuit redundancy in the pulse code modulation telemetry equipment
  • Eliminate the VHF lunar stay antenna
  • Delete one of two redundant buses in the electrical power system
  • Move the batteries for the explosive devices (along with the relay and fuse box assembly) from the ascent to the descent stage
  • Reduce "switchover" time (the length of time between switching from the oxygen and water systems in the descent stage to those in the ascent portion of the spacecraft and the actual liftoff from the moon's surface). Grumman had recommended that this span be reduced from 100 to 30 min; Rector urged Grumman to reduce it even further, if possible. He also ordered the firm to give "additional consideration" to the whole concept for the oxygen and water systems:
    1. in light of the decisions for an all-battery LEM during translunar coast; and
    2. possibility of transferring water from the CM to the LEM.
But ASPO vetoed other proposals to lighten the spacecraft:

  • Delete the high intensity light. Because the rendezvous radar had been eliminated from the CSM, Rector stated flatly that the item could "no longer be considered as part of the weight reduction effort."
  • Combine the redundant legs in the system that pressurized the reaction control propellants, to modularize" the system. MSC held that the parallel concept must be maintained.
  • Delete the RCS propellant manifold.
  • Abridge the spacecraft's hover time. Though the Center was reviewing velocity budgets and control weights for the spacecraft, for the present ASPO could offer "no relief."
And lastly, Rector responded to Grumman's proposals for staging components of the extravehicular mobility unit (EMU). These proposals had been made on the basis of a LEM crew integration systems meeting on January 27, at which staging had been explored. Those discussions were no longer valid, however. MSC had since required a capability for extravehicular transfer to the LEM. In light of this complicating factor, MSC engineers had reevaluated the entire staging concept. Although staging still offered "attractive" weight reductions, they determined that, at present, it was impractical. Accordingly, Rector informed Robert S. Mullaney, the LEM Program Manager at Grumman, that his firm must revert to the pre-January 27 position - i.e., the EMU and other assorted gear must be stored in the ascent stage of the spacecraft.

Letter, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Weight Reduction Study Status," March 29, 1965.

March 29-April 4

Beech Aircraft Corporation stopped all end-item acceptance tests of hydrogen and oxygen tanks as a result of interim failure reports issued against three tanks undergoing tests. Failures ranged from exceeding specification tolerances and failure to meet heat leak requirements to weld failure on the H2 tank. Beech would resume testing when corrective action was established and approved by North American.

NAA, "Project Apollo Spacecraft Test Program Weekly Activity Report (Period 29 March 1965 through 4 April 1965)," p. 4; "Apollo Monthly Progress Report," SID 62-300-36, p. 12.

March 31

MSC requested that Grumman incorporate in the command list for LEMs 1, 2, and 3 the capability for turning the LEM transponder off and on by real-time radio command from the Manned Space Flight Network. Necessity for capability of radio command for turning the LEM transponder on after LEM separation resulted from ASPO's decision that the LEM and Saturn instrument unit S-band transponders would use the same transmission and reception frequencies.

TWX, W. F. Rector III, MSC, to GAEC, Attn: R. S. Mullaney, March 31, 1965.

During the Month

MSC directed Grumman to use supercritical helium only in the descent stage of the LEM; Grumman completed negotiations with AiResearch for the storage system.

"Monthly Progress Report No. 26," LPR-10-42, p. 1.

During the Month

Bell Aerosystems Company received Grumman's go-ahead to resume work on the thrust chamber of the LEM ascent engine. Bell conducted a dozen stability tests using an injector fitted with a 31.75 mm (1.25 in), Y-shaped baffle. Thus far, the design had recovered from every induced disturbance (including widely varied fuel-to-oxygen ratios). Also, to ease the thermal soakback problem, Bell planned to thicken the chamber wall.

"Monthly Progress Report No. 26," LPR-10-42, pp. 8, 17.

During the Month

Grumman recommended to MSC that the stroking gear pad be used on the LEM and that design effort to refine crushing performance should continue.

Ibid., p. 1.

During the Month

Grumman reported the status of their development program on the LEM landing gear. The firm was:

  • Continuing hardware design on the 424-cm (167-in) gear.
  • Testing honeycomb crushing characteristics at velocities up to 7.62 m per sec (25 fps).
  • Studying high-density honeycomb materials that would still be compatible with a lightweight secondary strut.
  • Studying the possibility of strengthening the rim of the fixed (non stroking) footpad.
  • Designing a boilerplate footpad for use in drop tests.
  • Planning drops of a 406-cm (160-in) gear.
  • Continuing testing on primary and secondary struts.
Ibid., pp. 13-14.

During the Month

Space Technology Laboratories' major problems with the LEM descent engine, Grumman reported, were attaining high performance and good erosion characteristics over the entire throttling range.

Ibid., p. 19.

During the Month

Three flights were made with the Lunar Landing Research Vehicle (LLRV) for the purpose of checking the automatic systems that control the attitude of the jet engine and adjusting the throttle so the jet engine would support five-sixths of the vehicle weight.

On March 11 representatives of Flight Research Center (FRC) visited MSC to discuss future programs with Warren North and Dean Grimm of Flight Crew Support Division. A budget for operating the LLRV at FRC through fiscal year 1966 was presented. Consideration was being given to terminating the work at FRC on June 30, 1966, and moving the vehicles and equipment to MSC.

A contract was placed (on March 17) to erect a 12.19 x 12.19-m (40 x 40 ft) building at the south base area of FRC, where the LLRV was flown. Construction was expected to be complete in 60 days and the building should reduce LLRV interference with Air Force operations and enhance the preflight procedures.

Letter, Office of Director, FRC, to NASA Headquarters, "Lunar Landing Research Vehicle Progress Report No. 21 for period ending March 31, 1965,"sgd. De E. Beeler for Paul F. Bikle, April 7, 1965.