The Apollo Spacecraft - A Chronology.|
Advanced Design, Fabrication, and Testing
September 1North American conducted another in their series of impact tests with boilerplate 28. This drop tested the toroidal section of the spacecraft (heatshield and equipment bay structure) in impact at high angle and maximum horizontal velocity. The spacecraft suffered no visible damage. Some water leaked into the vehicle, but this was blamed on the boilerplate structure itself and the apex-down attitude after impact.
"Apollo Monthly Progress Report," SID 62-300-41, p. 1; MSC, "ASPO Weekly Management Report, September 2-9, 1965."
September 1A LEM ascent engine exploded during altitude firings at Arnold Engineering Development Center (AEDC). In subsequent investigations, Bell Aerosystems researchers concluded that the failure probably resulted from raw propellants being accidentally forced into the engine at the end of the second run, thus damaging the injector. The explosion, which occurred at the start of the third run, in turn followed an uncontrolled flow of propellants into the engine. As a result of this accident, Bell made several changes in hardware fabrication. Also, the company planned additional firings, under conditions similar to those at AEDC when the explosion occurred, to try to determine exactly the cause.
MSC, "Minutes of Senior Staff Meeting, September 10, 1965,"p. 1; memorandum, A. L. Madyda, MSC, to Chief, Propulsion and Power Division, "Report on trip to Bell Aerosystems, September 13-14, 1965," September 16, 1965; memorandum, Madyda, to Chief, Propulsion and Power Division, "Trip to Bell on September 30, 1965," October 4, 1965.
September 1-8MSC advised officials at North American's Tulsa Division that their concept for external panel retention cables on the adapter was unacceptable. While the Tulsa people agreed with Houston's objections, because of orders from Downey they had no authority to change the design. Structures and Mechanics Division reported that North American's "continued apathy . . . to redesign the system" threatened a schedule delay.
"ASPO Weekly Management Report, September 2-9, 1965."
September 2-9MSC's Flight Operations Division requested an investigation of the feasibility of performing an abort from an inoperative S-IVB booster on the AS-206 unmanned LEM mission.
Ibid.; memorandum, R. W. Lanzkron, MSC, to Chief, Systems Engineering Division, "AS-206 Preliminary Abort Requirements," September 10, 1965.
September 3NASA Associate Administrator for Manned Space Flight George E. Mueller summarized for Administrator James E. Webb the status of the LEM tracking systems. The LEM rendezvous radar system, which had been under development since 1963, was expected to be available when needed for flight missions. Technical studies had shown that an Optical Tracker System offered weight and reliability advantages with no reduction in LEM performance. Hughes Aircraft Company was developing an Optical Tracking System as a back-up to the rendezvous radar.
Memorandum, Mueller to Webb, "LEM Tracking Systems," September 3, 1965.
September 3To aid in defining abort limits for the emergency detection system, MSC authorized North American to determine the ultimate strength of the spacecraft based on failure trajectories of the Saturn IB and Saturn V vehicles.
Letter, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division, "Contract Change Authorization No. 407," September 3, 1965; memorandum, Owen E. Maynard, MSC, to Chief, Flight Control Division, "Range Safety Destruct Time Delay for Saturn IB & V," September 27, 1965.
September 3MSC requested Grumman to review the following ascent and descent pressurization system components in the propulsion subsystem for materials compatibility with certain propellants:
Letter, R. Wayne Young, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, Internal compatibility of LEM Ascent and Descent Propulsion Subsystem pressurization system components with fuel and oxidizer propellant vaporizer, Hydrazine-Unsymmetrical Dimethyl Hydrazine and Nitrogen Tetroxide, respectively," September 3, 1965.
September 8William A. Lee, ASPO, pointed out to the MSC Thermo-Structures Branch that Grumman was engaged in a strenuous weight reduction effort and that, when feasible, MSC should accept the proposed changes. In the area of thermal control, Grumman was investigating the use of etched aluminum surfaces to replace thermal paint. It was expected that the change was feasible and that approximately 11 kg (24 lbs) of inert weight would be saved on each stage of the LEM. In addition, Grumman was investigating the applicability of this technique to the landing gear components.
Grumman was also studying substitution of an aluminum-mylar nonrigid outer heatshield with plastic standoffs for current rigid ascent and descent heatshields. The potential inert weight saving would be about 84 kg (185 lbs). Lee requested that Thermo-Structures Branch stay in close contact with these developments.
Memorandum, William A. Lee, MSC, to Thermo-structures Branch, Attn: J. A. Smith, Jr., "LEM weight reductions in the area of thermal control," September 8, 1965.
September 8Assistant ASPO Manager William A. Lee told the General Instrumentation Branch of the Instrumentation and Electronic Systems Division Grumman was preparing a proposal for use of the LEM vehicle as an electrical ground. The plan was to adopt a single wire system selectively for those circuits not susceptible to electrical transients. Lee said Grumman estimated a weight savings of 27 kg (60 lbs) in the ascent stage and 9 kg (20 lbs) in the descent stage. The proposal was expected to be available to NASA by October 1 and Lee had committed NASA to a decision within three weeks of receipt of the plan.
Memorandum, William A. Lee, MSC, to General Instrumentation Branch, Attn: A. H. Campos, "Use of LEM vehicle structure as electrical ground return," September 8, 1965.
September 9-10MSC requested Grumman and North American to study the possibility of taking the guillotine that Grumman had developed for the LEM's interstage umbilical and using it as well to sever the two umbilicals linking the LEM to the adapter. In this manner, North American's effort to develop these cutters might be eliminated; LEM-adapter interface would be simplified; and a significant monetary savings could be effected without schedule impact.
MSC, "ASPO Weekly Management Report, September 9-16, 1965"; ASPO, "Abstract of Proceedings, Ground Test Requirements Meeting No. 4, September 9 and 10, 1965," September 16, 1965.
September 9-16Northrop-Ventura canceled a parachute test because of problems with the reefing line rings and the main parachute bags. North American was looking into these problems which, it was anticipated, would affect both blocks of spacecraft.
MSC, "ASPO Weekly Management Report, September 9-16, 1965."
September 10Because of recent changes in the design of the space suit, Motorola, under its contract for suit communications antennas, began concentrating on the development of antennas for the back pack rather than on the helmet.
Letter, Richard S. Johnston, MSC, to R. E. Breeding, Hamilton Standard Division, "Technical directive on SSC helmet mounted antenna," September 10, 1965; MSC, "ASPO Weekly Management Report, September 16-23, 1965."
With the continued frustrations of fighting the weight problem on both the CM and LEM it was necessary that both NASA and contracting personnel maintain a sense of humor. The above was used in slide form at a meeting at MSC.
Owen E. Maynard, Chief of Systems Engineering Division, advised ASPO Manager Joseph F. Shea of the major technical problems currently plaguing Apollo designers:
September 10NASA began recruiting additional pilot-astronauts, to begin training the following summer.
MSC News Release 65-79, "NASA to Select Additional Pilot-Astronauts," September 10, 1965.
September 12Hurricane Betsy hit the United States and Apollo Program Director Samuel C. Phillips presented an interim report to NASA Associate Administrator Robert C. Seamans, Jr., concerning the effects of the storm on NASA property and programs:
September 13ASPO Manager Joseph F. Shea announced a new plan for controlling the weight of Apollo spacecraft. Every week, subsystem managers would report to a Weight Control Board (WCB), headed by Shea, which would rule on their proposals for meeting the target weight for their systems. Three task forces also would report to the WCB on the way to lighten the spacecraft:
September 14As a result of discussions with North American and Aerojet-General, MSC ordered several changes to the service propulsion engine:
TWX, J. B. Alldredge, MSC, to NAA, Space and Information Systems Division, Attn: J. C. Cozad, subject: "SPS Engine Changes and Checkout," September 14, 1965.
September 14At a status meeting at Grumman on LEM-1, MSC learned that, as a result of welding problems, the vehicle's ascent stage was about four weeks behind schedule.
Memorandum, R. A. Newlander to W. J. Gaylor, RASPO-Bethpage, "LEM-1 Status Meeting, 9/14/65," September 17, 1965; letter, R. Wayne Young, MSC, to GAEC, Attn: R. S. Mullaney, "Contract NAS 9-1100, LEM-1 Status Meeting Number Four," September 21, 1965.
September 15Flight Crew Support Division defined the minimum time required to assure adequate crew training in the Apollo Mission Simulators. Individual part task training in the simulators required 36 hrs for each of six astronauts (prime and backup crews), a total of 216 hrs; each of the two crews would require 40 hrs of crew mission task training, 120 hrs of crew specific mission training, and nine hrs each of crew integrated mission (with ground crews) training, a total of 169 hrs per crew or a total of 338 hrs.
It was estimated that the simulator would be operational on an average of 30 hours a week, based on experience in other programs. Thus, eight months of simulator availability would be required prior to the AS-204 launch date - one month of training verification plus 29 weeks for crew training.
The needed dates for simulators were: Apollo Mission Simulator No. 1, fully operational January 15, 1966, with spacecraft 012 modification kit delivery complete on March 18, 1966; Apollo Mission Simulator No. 2 delivery in 012 configuration April 15, 1966, to be fully operational June 6, 1966.
Memorandum, Warren J. North, MSC, to Chief, Systems Engineering Division, "Simulator training requirements to support the Apollo missions," September 15, 1965.
September 16MSC's Assistant Director for Flight Operations, Christopher C. Kraft, Jr., told ASPO Manager Joseph F. Shea that postlanding operational procedures require that recovery force personnel have the capability of gaining access into the interior of the CM through the main crew hatch. This was necessary, he said, so recovery force swimmers could provide immediate aid to the crew, if required, and for normal postlanding operations by recovery engineers such as spacecraft shutdown, crew removal, data retrieval, etc.
Kraft said the crew compartment heatshield might char upon reentry in such a manner as to make it difficult to distinguish the outline of the main egress hatch. This potential problem and the necessity of applying a force outward to free the hatch might demand use of a "crow bar" tool to chip the ablator and apply a prying force on the hatch.
Since this would be a special tool, it would have to be distributed to recovery forces on a worldwide basis or be carried aboard the spacecraft. Kraft requested that the tool be mounted onboard the spacecraft in a manner to be readily accessible. He requested that the design incorporate a method to preclude loss of the tool - either by designing the tool to float or by attaching it to the spacecraft by a lanyard.
Memorandum, Kraft to Shea, "Apollo Crew Hatch Tool," September 16, 1965.
September 16The Assistant Chief for Electronic Systems notified ASPO that the proposed Grumman plan to repackage the LEM pulse command modulated and timing electronic assembly (PCMTEA) had been discussed and investigated and that the Instrumentation and Electronic Systems Division (IESD) concurred with the proposal.
Following is the impact to the PCMTEA as a result of Grumman's proposed changes:
September 16-17North American and its subcontractor, LTV, conducted a design review on the environmental control system radiator for the Block II CSM. Both parties agreed upon a backup effort (i.e., a narrower selective stagnation panel), which would be more responsive to thermal changes in the spacecraft. Testing of this backup design could follow that of the prototype and still meet the design release.
Memorandum, Frank H. Samonski, Jr., MSC, to Gary G. Metz, "Environmental control system (ECS) attitude constraints for Spacecraft 012," September 14, 1965; "ASPO Weekly Management Report, September 16-23, 1965."
September 16-17A design review on the attitude controller for the LEM was held at Honeywell. Flight Crew Support Division reported that the device seemed "highly optimized functionally, operationally, and weight wise."
"ASPO Weekly Management Report, September 16-23, 1965"; GAEC, "Monthly Progress Report No. 32," LPR-10-48, October 10, 1965, p. 14; TWX, R. Wayne Young, MSC, to GAEC, Attn: R. S. Mullaney, October 14, 1965.
September 16-23Systems Engineering Division (SED) reported that, on the basis of data from SA-4, 8, and 9 flights, the thermal coating of the spacecraft suffered considerable damage. This degradation was caused by the S-IV retro motor and/or the tower jettison motor. SED advised that a thorough analysis was scheduled shortly at TRW to look into the entire area of thermal factors and the performance of ablative coating. However, North American refused to acknowledge the existence of any such thermal problem, SED said. The firm's "continued inactivity" was described as a "major obstacle" to solving the problem.
"ASPO Weekly Management Report, September 16-23, 1965"; memorandum, James A. Smith, MSC, to Project Officer, C and SM, ASPO, "Technical Evaluation, Justification, and Plan of Action for Instrumentation to determine effects of TJM Impingement, RECP 461," September 27, 1965.
September 16-23NASA and the Atomic Energy Commission (AEC) agreed that AEC would provide radioisotope thermoelectric generators which would power each Apollo Lunar Surface Experiments Package for an operating period of one year on the lunar surface.
"ASPO Weekly Management Report, September 16-23, 1965"; memorandum, Robert E. Vale, MSC, to Chief, Systems Engineering Division, "Radioisotope Thermoelectric Generator," September 27, 1965.
September 16-23Grumman established the final design parameters for the landing gear of the LEM (both primary and secondary struts). It was anticipated that this newer design would be between 9 and 14 kg (20 and 30 lbs) lighter than the earlier gear.
"ASPO Weekly Management Report, September 16-23, 1965"; "Monthly Progress Report No. 32," LPR-10- 48, pp. 10, 12.
September 16-October 15North American evaluated the compatibility of spacecraft 012 with its mission, AS-204, the first manned Apollo flight. The manufacturer determined that, by using roll-stabilized attitude during most of the flight, the vehicle could remain aloft for about 13½ days. The only onboard expendables termed marginal were cryogenics and the propellant supply in the SM's reaction control system (which, for added safety, would offer a redundant means of braking the vehicle out of orbit).
NAA, "Apollo Monthly Progress Report," SID 62-300-42, November 1, 1965, p. 3; memorandum, Robert V. Battey, MSC, to Chief, Apollo Trajectory Support Office, "Spacecraft systems and attitude constraints for mission AS-204," September 14, 1965.
September 17The basic structure of Apollo CM simulator "A," around which a full-scale mockup of the CM crew stations would be built, was delivered to MSC. Flight Crew Support Division would use the mockup for crew familiarization, procedures training, and equipment evaluation.
"ASPO Weekly Management Report, September l6-23, 1965."
September 20MSC's Director, Robert R. Gilruth, sent a detailed history of actions taken in regard to development of the Apollo Extravehicular Mobility Unit, and recommended three changes not consistent with the overall procurement plan previously approved by NASA Headquarters:
Letter, Gilruth to NASA Headquarters, Attn: George E. Mueller, "Procurement plan for the Apollo Extravehicular Mobility Unit and EMU ground support equipment development and fabrication," sgd. George M. Low, September 20, 1965.
September 20On the basis of studies by both MSC and Grumman on LEM landing criteria, Engineering and Development Directorate determined that contractor and customer alike favored reducing landing velocity requirements for the spacecraft. The two did not see eye to eye on how far these requirements should be reduced, however, and MSC would study the problem further.
Memorandum, James A. Chamberlin, MSC, to Distr., "Status of LEM landing studies," September 20, 1965.
September 21ASPO Manager Joseph F. Shea decided that no device to indicate a failure of the secondary gimbal motor in the service propulsion system (SPS) was necessary on Block I spacecraft. Two factors shaped Shea's decision:
Memorandum, Shea, MSC, to Assistant Director for Flight Operations, "Service Propulsion System (SPS) Secondary Gimbal Motor Fail Indication," September 21, 1965.
September 27NASA's Administrator James E. Webb, Deputy Administrator Hugh L. Dryden, and Associate Administrator Robert C. Seamans, Jr., selected Ling-Temco-Vought from a total of 17 proposers for contract negotiations for a one-year cost-plus-award-fee contract with options to extend for two one-year periods, to provide operational laboratory support services for the Apollo spacecraft program at the White Sands (N. Mex.) Test Facility. The selection was based upon the presentation of a source evaluation board and comments of key officials concerned. The Associate Administrator for Manned Space Flight was asked to issue appropriate instructions to ensure that the contract negotiating team follow the negotiation objectives as presented to them.
Memorandum, Deputy Associate Administrator, NASA, to Associate Administrator for Manned Space Flight, "Selection of Contractor to Provide Operational Laboratory Support Services for the Apollo Spacecraft Program at the White Sands Test Facility," sgd. Earl D. Hilburn, September 27, 1965.
September 22-29North American proposed an additional pane of glass for the windows on Block II CMs. Currently, both blocks of spacecraft had one pane. Should meteoroids pit this pane, the window could fail during reentry at lunar velocities. The meteoroid protection group in Structures and Mechanics Division were evaluating North American's proposal, which would add about 10.43 kg (23 lbs) to the vehicle's weight. No such added protection was required on Block I spacecraft.
MSC, "ASPO Weekly Management Report, September 23-30, 1965"; "Apollo Monthly Progress Report," SID 62-300-41, p. 5.
September 24The Critical Design Review (CDR) of the LEM, tentatively planned during the week of September 27, 1965, at Grumman, was rescheduled as a series of reviews beginning in November 1965 and ending in January 1966. The schedule was to apply with five teams participating as follows: Structures and Propulsion, November 8-11, Team Captain: H. Byington; Communications, Instrumentation, and Electrical Power, December 6-9, Team Captain: W. Speier; Stabilization and Control, Navigation and Guidance, and Radar, January 10-13, Team Captain: A. Cohen; Crew Systems, January 10-13, Team Captain: J. Loftus; and Mission Compatibility and Operations, January 24-27, Team Captain: R. Battey.
Memorandum, Owen E. Maynard, MSC, to Distr., "Critical Design Review of LEM," September 24, 1965.
MSFC marked completion of its first Saturn V S-IC booster September 26,1965, with a brief ceremony in front of the assembly shop. A wide-angle camera caught this view as the ceremony was about to start with MSFC Director Wernher von Braun at the microphone (left).
September 27MSC directed Grumman to draw up a complete list of all nonmetallic materials used in the habitable area of the LEM, including type, use, location, weight, and source of all such materials.
Letter, James L. Neal, MSC, to GAEC, Attn: John C. Snedeker, "Contract NAS 9-1100, Contract Change Authorization No. 136, Exhibit E, Nonmetallic Materials in Habitable Area," September 27, 1965.
September 27Officials from the U.S. Public Health Service (PHS) and the Department of Agriculture met at MSC to discuss informally the problem of back contamination. They listened to briefings on the mission profile for Apollo; reentry heating rates; present thinking at the Center on the design of the Lunar Sample Receiving Station (LSRS); and MSC's plans (none) for quarantining the astronauts.
James Goddard, Assistant Surgeon General in PHS, presented three broad areas of concern:
On October 15, Lawrence B. Hall, Planetary Quarantine Officer in NASA's Office of Space Science and Applications, summarized for Deputy Administrator Hugh L. Dryden the September 27 meeting, and recommended that such informal discussions continue. "I believe," he told Dryden, "that . . . the Manned Spacecraft Center is more fully aware of the point of view of the regulatory agencies on this matter. Unfortunately, the regulatory agencies still do not understand the reasons for the Manned Spacecraft Center's reluctance to face this problem." [To appreciate MSC's "reluctance," see October 29, 1965.]
Memorandum, Hall, NASA, to Deputy Administrator, "Informal conference on back contamination problems," October 15, 1965, with enclosure: "Summary, Informal Conference on Back Contamination Problems," undated.
September 27North American evaluated the CSM's communications capability with the unified S-band system using attitude data published with the AS-501 (spacecraft 017) preliminary reference trajectory. The trajectory selected to achieve the desired entry conditions had a maximum altitude at apogee of about 16,668 km (9,000 nm). At this altitude, the maximum range to a Manned Spacecraft Flight Network (MSFN) station was about 20,372 km (11,000 nmi). Since a high-gain antenna was not installed on spacecraft 017, communications depended on the S-band omnidirectional antennas. In order to verify their adequacy, directions to the MSFN stations were computed and system circuit margins were derived. North American concluded that the margins were inadequate to support high-bit-rate telemetry for about three hours of the mission. Modification of the planned CSM attitude produced significant improvement (about 17 decibels) in communications. The contractor also proposed a relocation of range ships to improve performance.
"Apollo Monthly Progress Report," SID 62-300-42, p. 3; TWX, C. L. Taylor, MSC, to NAA, Space and Information Systems Division, Attn: J. C. Cozad, subject: "Mission 501/Spacecraft 017 Compatibility Evaluation," September 27, 1965.
September 28-30Representatives from MSC, David Clark, Hamilton Standard, and Westinghouse met at North American, where they negotiated and signed most of the interface control documents (ICD) for the space suit and associated equipment. Of the ICD's yet unresolved, only two involved problems that could have a significant effect on hardware design:
September 29Ralph S. Sawyer, Chief of the Instrumentation and Electronic Systems Division, advised ASPO Manager Shea of current problems with antennas for the Apollo spacecraft:
September 29Apollo Program Director Samuel C. Phillips issued the flight directive for the AS-202 mission, which spelled out the general flight plan, objectives, and configuration of both spacecraft and launch vehicle.
OMSF Directive M-D MA 1400.011, "Apollo Program Flight Mission Directive for Apollo-Saturn 202 Mission," September 29, 1965.
September 29The Critical Design Review (CDR) of the Block II CSM was scheduled to be conducted in November and December 1965, with the first phase being held November 15-18, and the second phase December 13-17.
The first phase activity would be a review of drawings, schematics, procurement specifications, weight status, interface control drawings, failure analysis, proposed specification change notices, and specification waivers and deviations. The second phase of the review would be a physical inspection of the mockup of the Block II CSM.
The review would be conducted by review teams organized in the several areas and headed by team captains, as follows: Structures and Propulsion, O. Ohlsson; Communications, Instrumentation, and Electrical Power, W. Speier; Stabilization and Control, Guidance and Navigation, A. Cohen; Crew Systems, J. Loftus; and Mission Compatibility and Operations, R. Battey.
Memorandum, Chief, Systems Engineering Division, MSC, to Distr., "Critical Design Review of Block II CSM," sgd. Harry W. Byington, September 29, 1965.
September 29-30The Mission Operations Organization had been under continued review and discussion and on September 29 and 30 in New Orleans, La., a meeting was held between George E. Mueller, James C. Elms, Robert R. Gilruth, and George M. Low. General agreement was reached on a method of operation: The Mission Operations Director would represent the Associate Administrator for Manned Space Flight in all operational areas and would be responsible to the Associate Administrator for Manned Space Flight for the execution of all NASA manned spaceflight missions.
The people responsive to the Missions Operations Director (in the same sense as Center Program Managers are responsible to Headquarters Program Directors) are:
It was agreed that a better definition of responsibility between Program Office and Mission Operations Directorate in OMSF was required. It was also agreed that for all flight operational areas MSC would prefer to have the Assistant Director for Flight Operations act as its single point of contact. The Assistant Director for Flight Operations would represent Flight Crew Operations and Medical Operations in the mission operations area.
Memorandum, George M. Low, "Mission Operations Discussions," October 4, 1965; Informal Memorandum, George M. Low to Distr., October 15, 1965, with enclosure.
September 30-October 7Pressure loading and thermal tests were completed on the types of windows in the Block I CM. The pressure tests demonstrated their ability to withstand the ultimate stresses (both inward and outward) that the CM might encounter during an atmospheric abort. The thermal simulations qualified the windows for maximum temperatures anticipated during reentry at lunar velocities.
"ASPO Weekly Management Report, September 30-October 7, 1965."
September 30-October 7Flight Projects Division advised that, on the basis of current weight studies, the aft heatshield on Block I CMs must be thinned. North American had said that this change would not affect schedules, but felt some concern about the heat sensors. Accordingly, Structures and Mechanics Division (SMD) ordered North American to proceed with this weight reduction on the hardware for spacecraft 011, 012, and 014 (but ensuring that the orbital decay required for Block I manned missions would still be met). The sensors on 011's heatshield would be adapted to the new thickness. SMD anticipated that these changes would cost about $500,000 and would probably delay by about four weeks delivery of the 011 heatshield from Avco.
"ASPO Weekly Management Report, September 23-30, 1965"; "ASPO Weekly Management Report, September 30-October 7, 1965"; memorandum, R. W. Lanzkron and O. E. Maynard, MSC, to Manager, ASPO, "Weight Reduction for Block I Aft Heat Shield," October 8, 1965; memorandum, Joseph N. Kotanchik, MSC, to Manager, ASPO, "Flight Configuration of SC 011," October 18, 1965.
September 30Crew Systems Division defined the survival equipment that MSC would procure for Apollo spacecraft. Fifteen survival sets would be needed for Block I and 30 for Block II CMs.
Memorandum, R. E. Smylie, MSC, to Chief, Crew Systems Division, "Apollo Block I and Block II survival equipment procurement," September 30, 1965.
During the MonthBell Aerosystems reported on stability and ablative compatibility testing of the first bipropellant-cooled injector baffle for the ascent engine of the LEM. Combustion was stable; however, streaking on the injector face forced Bell to halt ablative testing after only 60 seconds of operation.
"Monthly Progress Report No. 32," LPR-10-48, pp. 1, 11.
During the MonthThirteen flights were made with the lunar landing research vehicle. Two of those flights were devoted to mulling the lunar simulation system; the remaining 11 flights were devoted to research with the attitude control system in the rate command mode. Nine landings were made in the lunar simulation mode.
On flight 1-34-94F the lunar simulation mode worked perfectly and no drift was encountered during more than one minute of hovering flight. The landing was made in the simulation mode for the first time on this flight.
Letter, Office of Director, Flight Research Center, to NASA Headquarters, "Lunar Landing Research Vehicle progress report No.27 for the period ending September 30, 1965," sgd. Paul F. Bikle, October 14, 1965.
September-OctoberGrumman advised MSC of major troubles plaguing development of the LEM's descent engine. These included problems of weight, chamber erosion, mixtures, valves, combustion instability, and throttle mechanisms (which Grumman said could delay delivery of LEM 1 and the start of qualification testing).
"Monthly Progress Report No. 32," LPR-10-48, pp. 3, 11; GAEC, "Monthly Progress Report No. 33," LPR- 10-49, November 10, 1965, p. 3.