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The STG New Projects Panel (proposed by H. Kurt Strass in June) held its first meeting to discuss NASA's future manned space program. Present were Strass, Chairman, Alan B. Kehlet, William S. Augerson, Jack Funk, and other STG members. Strass summarized the philosophy behind NASA's proposed objective of a manned lunar landing : maximum utilization of existing technology in a series of carefully chosen projects, each of which would provide a firm basis for the next step and be a significant advance in its own right. Each project would be an intermediate practical goal to focus attention on the problems and guide new technological developments. The Panel considered the following projects essential to the goal of lunar landing and return : a detailed investigation of the earth's radiation belts, recovery of radiation belt probes carrying biological specimens, an environmental satellite three men for two weeks, lunar probes, lunar reconnaissance (both manned and automatic), and lunar landing beacons and stores. The Panel recommended that work start immediately on an advanced recovery capsule that would incorporate the following features: reentry at near lunar return velocity, maneuverability both in space and in the atmosphere, and a parachute recovery for an earth landing. Kehlet was assigned to begin a program leading to a "second-generation" space capsule with a three-man capacity, space and atmospheric maneuverability, advanced abort devices, potential for near lunar return velocity, and advanced recovery techniques.
At the second meeting of the Apollo Technical Liaison Group for Configurations and Aerodynamics at STG, presentations were made on Apollo-related activities at the NASA Centers: heatshield tests (Ames Research Center); reentry configurations (Marshall Space Flight Center); reentry configurations, especially lenticular (modified) and spherically blunted, paraglider soft-landing system, dynamic stability tests, and heat transfer tests (Langley Research Center); tumbling entries in planetary atmospheres (Mars and Venus) (Jet Propulsion Laboratory); air launch technique for Dyna-Soar (Flight Research Center); and steerable parachute system and reentry spacecraft configuration (STG). Work began on the background material for the Apollo spacecraft specification.
NAA's Space and Information Systems Division selected four companies as subcontractors to design and build four of the major Apollo spacecraft systems. The Collins Radio Company, Cedar Rapids, Iowa, received the telecommunications systems contract, worth more than $40 million; Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., received the stabilization and control systems contract, $30 million; AiResearch Manufacturing Company, division of The Garrett Corporation, Los Angeles, Calif., was awarded the environmental control system contract, $10 million; and Radioplane Division of Northrop Corporation, Van Nuys, Calif., was selected for the parachute landing system contract, worth more than $1 million. The total cost for the initial phase of the NAA contract was expected to exceed $400 million.
The command module crew couch was repositioned and redesigned because of numerous problems. In the new design, an adjustable hand controller, similar to that used on the X-15, would be attached to an adjustable arm rest. The head rest could be regulated for an approximate four-inch movement, while the side head support was limited in movement for couch-module clearance. The adjustable leg support included a foot controller which could be folded up.
The center couch, including the crewman parachute and survival kit, could be folded out to a sleep position and stowed under either remaining couch. Allowance was made for the crewman to turn over.
Principal problems remaining were the difficulty of removing the center couch and providing the clearances needed for the couch positions specified for various phases of the lunar mission.
Telescope requirements for the spacecraft were modified after two study programs had been completed by NAA.
A study on the direct vision requirement for lunar landing showed that, to have a simultaneous direct view of the lunar landing point and the landing feet without changing the spacecraft configuration, a periscope with a large field of view integrated with a side window would be needed. A similar requirement on the general-purpose telescope could thus be eliminated, reducing the complexity of the telescope design.
Another study showed that, with an additional weight penalty of from five to ten pounds, an optical drift indicator for use after parachute deployment could easily be incorporated into the general-purpose telescope.
A 70-mm pulse camera was selected by NAA for mission photodocumentation. The camera was to be carried in the upper parachute compartment. Because of the lack of space and the need for a constant power supply for a 35-watt heating element, NAA was considering placing the camera behind the main display panel. The advantages of this arrangement were that the camera would require less power, be available for changing magazines, and could be removed for use outside the spacecraft.
One 16-mm camera was also planned for the spacecraft. This camera would be positioned level with the commander's head and directed at the main display panel. It could be secured to the telescope for recording motion events in real time such as rendezvous, docking, launch and recovery of a lunar excursion module, and earth landing; it could be hand-held for extravehicular activity.
Layouts of a command module (CM) telescope installation in the unpressurized upper parachute compartment were completed by NAA. The concept was for the telescope to extend ten inches from the left side of the spacecraft. The light path would enter the upper bulkhead through the main display panel to an eyepiece presentation on the commander's side of the spacecraft. A static seal (one-half-inch-thick window) would be used to prevent leakage in the pressurized compartment. The installation was suitable for use in the lunar orbit rendezvous mission and would allow one man in the CM to accomplish docking with full visual control.
Deletion of non-critical equipment and improvement of existing systems reduced the weight of the command and service modules by 1,239 pounds, with a target reduction of 1,500 pounds.
Among the items deleted from the command module (CM) were exercise and recreation equipment, personal parachutes and parachute containers located in the couches, individual survival kits, solar radiation garments, and eight-ball displays. A telescope, cameras and magazines considered scientific equipment, and a television monitor were deleted from the CM instrumentation system.
NAA completed a study of reentry temperatures. Without additional cooling, space suit inlet temperatures were expected to increase from 50 degrees F at 100,000 feet to 90 degrees F at spacecraft parachute deployment. The average heat of the command module inner wall was predicted not to exceed 75 degrees F at parachute deployment and 95 degrees F on landing, but then to rise to nearly 150 degrees F.
Elimination of the requirement for personal parachutes nullified consideration of a command module (CM) blowout emergency escape hatch. A set of quick-acting latches for the inward-opening crew hatch would be needed, however, to provide a means of egress following a forced landing. The latches would be operable from outside as well as inside the pressure vessel. Outside hardware for securing the ablative panel over the crew door would be required as well as a method of releasing the panel from inside the CM.
North American reported several problems involving the CM's aerodynamic characteristics; their analysis of CM dynamics verified that the spacecraft could - and on one occasion did - descend in an apex-forward attitude. The CM's landing speed then exceeded the capacity of the drogue parachutes to reorient the vehicle; also, in this attitude, the apex cover could not be jettisoned under all conditions. During low-altitude aborts, North American went on, the drogue parachutes produced unfavorable conditions for main parachute deployment.
As a parallel to the existing Northrop Ventura contract, and upon authorization by NASA, North American awarded a contract for a solid parachute program to the Pioneer Parachute Company. [A solid parachute is one with solid (unbroken) gores; the sole opening in the canopy is a vent at the top. Ringsail parachutes (used on the Northrop Ventura recovery system) have slotted gores. In effect, each panel formed on the gores becomes a "sail."]
At El Centro, Calif., Northrop Ventura conducted the first of a series of qualification tests for the Apollo earth landing system (ELS). The test article, CM boilerplate 3, was dropped from a specially modified Air Force C-133. The test was entirely successful. The ELS's three main parachutes reduced the spacecraft's rate of descent to about 9.1 meters (30 feet) per second at impact, within acceptable limits.
The Operational Evaluation and Test Branch of MSC's Flight Operations Division considered three methods of providing a recovery hoisting loop on the CM: loop separate from the spacecraft and attached after landing, use of the existing parachute bridle, and loop installed as part of the CM equipment similar to Mercury and Gemini. Studies showed that the third method was preferable.
MSC Flight Operations Division (FOD) recommended a series of water impact tests to establish confidence in the CM's recovery systems under a variety of operating conditions. FOD suggested several air drops with water landings under various test conditions. Among these were release of the main parachutes at impact, deployment of the postlanding antennas, actuation of the mechanical location aids, and activation of the recovery radio equipment.
At El Centro, Calif., CM boilerplate (BP) 3, a parachute test vehicle, was destroyed during tests simulating the new BP-6 configuration (without strakes or apex cover). Drogue parachute descent, disconnect, and pilot mortar fire appeared normal. However, one pilot parachute was cut by contact with the vehicle and its main parachute did not deploy. Because of harness damage, the remaining two main parachutes failed while reefed. Investigation of the BP-3 failure resulting in rigging and design changes on BP-6 and BP-19.
MSC made several changes in the CM's landing requirements. Impact attenuation would be passive, except for that afforded by the crew couches and the suspension system. The spacecraft would be suspended from the landing parachutes in a pitch attitude that imposed minimum accelerations on the crew. A crushable structure to absorb landing shock was required in the aft equipment bay area.
Apollo Pad Abort Mission I (PA-1), the first off-the-pad abort test of the launch escape system (LES), was conducted at WSMR. PA-1 used CM boilerplate 6 and an LES for this test.
All sequencing was normal. The tower-jettison motor sent the escape tower into a proper ballistic trajectory. The drogue parachute deployed as programmed, followed by the pilot parachute and main parachutes. The test lasted 165.1 seconds. The postflight investigation disclosed only one significant problem: exhaust impingement that resulted in soot deposits on the CM.
At El Centro, Calif., a drop test was conducted to evaluate a dual drogue parachute arrangement for the CM. The two drogues functioned satisfactorily. The cargo parachute used for recovery, however, failed to fully inflate, and the vehicle was damaged at impact. This failure was unrelated to the test objectives.
A joint North American-MSC meeting reviewed the tower flap versus canard concept for the earth landing system (ELS). During a low-altitude abort, MSC thought, the ELS could be deployed apex forward with a very high probability of mission success by using the tower flap configuration. The parachute system proposed for this mode would be very reliable, even though this was not the most desirable position for deploying parachutes. Dynamic stability of the tower flap configuration during high- altitude aborts required further wind tunnel testing at Ames Research Center. Two basic unknowns in the canard system were deployment reliability, and the probability of the crew's being able to establish the flight direction and trim the CM within its stability limits for a safe reentry. Design areas to be resolved were a simple deployment scheme and a spacecraft system that would give the crew a direction reference.
MSC directed North American to proceed with the tower flap as its prime effort, and attempt to solve the stability problem at the earliest possible date. MSC's Engineering and Development Directorate resumed its study of both configurations, with an in-depth analysis of the canard system, in case the stability problem on the tower flap could not be solved by the end of the year.
Boilerplate (BP) 19 was drop tested at El Centro, Calif., simulating flight conditions and recovery of BP-12. A second BP-19 drop, on April 8, removed all constraints on the BP-12 configuration and earth landing system. Another aim, to obtain information on vehicle dynamics, was not accomplished because of the early firing of a backup drogue parachute.
North American conducted the first drop test of boilerplate 28 at Downey, Calif. The test simulated the worst conditions that were anticipated in a three-parachute descent and water landing. The second drop, it was expected, would likewise simulate a landing on two parachutes. In the week preceding the drop, the MSC Structures and Mechanics Division had sounded a note of caution. The aft heatshield, they said, "might not respond to the impact loading as static loading." In this event, they predicted, pressures imposed on the heatshield would "greatly exceed" design allowables.
The drop appeared normal, but the spacecraft sank less than four minutes after hitting the water. Inspection of the vehicle immediately afterward disclosed that the heatshield had broken open on impact and that the welds of the stainless-steel honeycomb core had failed. The cabin interior also sustained considerable damage, especially the aft bulkhead and the cabin floor, which were forced upward and struck the crew couch. Three instrumented manikins were seated in the crew positions. The two outboard "crewmen" sustained 25 g's each at impact. The dummy in the second couch, however, suffered stresses of 50 g's, a condition that might euphemistically be called "unacceptable." MSC and North American personnel were investigating further.
A "pre-FRR" laid some preliminaries for the formal Flight Readiness Review (ERR) of boilerplate 23 (held at WSMR on December 4, 1964). Because the boost protective cover had not been designed to sustain the dynamic pressures that would follow deployment of the canards and vehicle "turn-around," North American was asked to analyze the possibility of its failing.
Several other problems were aired - fluttering of the canards and the likelihood of damage to the parachute compartment during jettisoning of the launch escape tower and the boost cover. Joseph N. Kotanchik, chief of the Structures and Mechanics Division, confidently reported to ASPO that "these items will also be resolved prior to the ERR."
A single main parachute was drop-tested at El Centro, Calif., to verify the ultimate strength. The parachute was designed for a disreef load of 11,703 kg (25,800 lbs) and a 1.35 safety factor. The test conditions were to achieve a disreef load of 15,876 kg (35,000 lbs. Preliminary information indicated the parachute deployed normally to the reefed shape (78,017 kg [17,200 lbs] force), disreefed after the programmed three seconds, and achieved an inflated load of 16,193 kg (35,700 lbs), after which the canopy failed. North American representatives would visit MSC during the week of December 14 to discuss this and other recent tests.
Changing the CM back-face temperature requirement from 600 degrees F at touchdown to 600 degrees F at parachute deployment threatened to increase the cabin air temperature. Physiologists at MSC had previously declared that the cabin temperature should not exceed 100 degrees F. The proposed change in the back-face requirement, North American reported, would raise the cabin's interior to 125 degrees F. MSC's Crew Systems Division reviewed these factors and decided the increased cabin temperature would not be acceptable.
Northrop-Ventura verified the strength of the dual drogue parachutes in a drop test at El Centro, Calif. This was also the first airborne test of the new mortar by which the drogues were deployed and of the new pilot parachute risers, made of steel cables. All planned objectives were met. The deployment sequence was perfect, and there was no apparent kinking of the risers.
In the course of this drop, six of the 12 cutters, which sever the reefing lines on the main parachutes, failed. This failure, together with another cutter malfunction during the previous month, signaled an intensive investigation at Ordco, the cutter manufacturer. Qualification of the severing device was thereby delayed.
On January 22, Northrop, North American, and MSC conducted a design review for the drogue system and found no discrepancies.
A 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.
Because 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.
To 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).
The Apollo earth landing system (ELS) was tested in a drop of boilerplate (BP) 19 at El Centro, Calif. The drop removed constraints on the ELS for BP-22; also, it was a "prequalification" trial of the main parachutes before the start of the full qualification test program.
During tests of the Apollo earth landing system (ELS) at El Centro, Calif., boilerplate (BP) 6A sustained considerable damage in a drop that was to have demonstrated ELS performance during a simulated apex-forward pad abort. Oscillating severely at the time the auxiliary brake parachute was opened, the spacecraft severed two of the electrical lines that were to have released that device. Although the ELS sequence took place as planned, the still-attached brake prevented proper operation of the drogues and full inflation of the mains. As a result, BP-6A landed at a speed of about 50 fps.
A drop in the boilerplate 6A series, using flight-qualifiable earth landing system (ELS) components, failed because the braking parachute (not a part of the ELS) did not adequately stabilize the vehicle. MSC invited North American and Northrop-Ventura to Houston to explain the failure and to recommend corrective measures.
Nine review item dispositions were submitted at the Block II critical design review concerning the earth landing system and shock attenuation system (struts). Six were on specifications, one on installation drawings, and two on capability. The two most significant were:
MSC Director Robert R. Gilruth wrote George E. Mueller, NASA OMSF, that plans were being completed for MSC in-house, full-scale parachute tests at White Sands Missile Range (WSMR), N. Mex. The tests would be part of the effort to develop a gliding parachute system suitable for land landing with manned spacecraft. Tests were expected to begin in July 1966, with about six tests a year for two or three years. Gilruth pointed out that although full-scale tests were planned for WSMR it would not be possible to find suitable terrain at that site, at Edwards Air Force Base, Calif., or at El Centro, Calif., to determine operational and system requirements for land landing in unplanned areas. Unplanned-area landing tests were cited as not a major part of the program but a necessary part. He pointed out that the U.S. Army Reservation at Fort Hood, Tex., was the only area which had the required variety of landing obstacle sizes and concentrations suitable for the unplanned-area tests. Scale-model tests had been made and would be continued at Fort Hood without interference to training, and MSC had completed a local agreement that would permit occasional use of the reservation but required no fiscal reimbursement or administrative responsibility by MSC. This action was in response to a letter from Mueller July 8, 1965, directing that MSC give careful consideration to transfer of parachute test activities to WSMR.
ASPO Manager George M. Low, in a letter to Richard E. Horner, Senior Vice President of Northrop Corp., following a phone call to Horner on Sept. 28, reiterated NASA's "continuing and serious concern with the quality control at Northrop Ventura on the Apollo spacecraft parachute system. In recent weeks, I have had many reports of poor workmanship and poor quality, both in the plant at Northrop Ventura and in the field at El Centro."
On October 20 Horner told Low he had taken time to assure himself of the best possible information available before replying and offered background on the situation: "The design effort goes back to 1961 and testing began at the El Centro facility in 1962. There was continuous operation of the test group at El Centro until 1966 when the completion of the Block II testing program dictated the closeout of our operation there. In our total activity, we have had a peak of 350 personnel assigned to the Apollo, with 20 of that number located at El Centro during the most active portion of the test program. When it was finally determined that the increased weight capability redesign was necessary for mission success, the program nucleus had been reduced to 30 personnel and the established schedule for the system re-design, test and fabrication requires a build-up to 250. . . . The schedule has also dictated the adoption of such procedures as concurrent inspection by the inspectors of Northrop, North American and NASA, a procedure which, I am sure, is efficient from a program point of view but is inherently risky in terms of the wide dissemination of knowledge concerning every human mistake. This is significant only from the point of view of the natural human failing to be more willing to share the responsibility for error than for success. . . . We do not intend in any way to share responsibility for these errors and expect to eliminate the potential for their recurrence. We have established standards of quality for this program that are stringent and uncompromising. . . . Even though the technical and schedule challenge is substantial, we are confident that by the time qualification testing is scheduled to start during the first week of December 1967 we will have a flawless operation. . . ."
A proposal to use a Ballute system rather than drogue parachutes to deploy the main chutes on the Apollo spacecraft was rejected. It was conceded that the Ballute system would slightly reduce dynamic pressure and command module oscillations at main parachute deployment. However, these advantages would be offset by the development risks of incorporating a new and untried system into the Apollo spacecraft at such a late date.
A parachute test (Apollo Drop Test 84-1) failed at EI Centro, Calif. The parachute test vehicle (PTV) was dropped from a C-133A aircraft at an altitude of 9,144 meters to test a new 5-meter drogue chute and to investigate late deployment of one of the three main chutes. Launch and drogue chute deployment occurred as planned, but about 1.5 seconds later both drogue chutes prematurely disconnected from the PTV. A backup emergency drogue chute installed in the test vehicle and designed to be deployed by ground command in the event of drogue chute failure also failed to operate. The PTV fell for about 43 seconds before the main chutes were deployed. Dynamic pressure at the time of chute deployment was estimated at about 1.2 newtons per square centimeter (1.7 pounds per square inch). All parachutes failed at or shortly after main parachute line stretch. The PTV struck the ground in the drop zone and was buried about 1.5 meters. An accident investigation board was formed at El Centro to survey mechanical components and structures, fabric components, and electrical and sequential systems. R. B. West, Earth Landing System Subsystem Manager, represented NASA in the investigation. It was determined that two primary failures had occurred:
On November 3, a preliminary analysis of the drop test failure was made at Downey Calif., with representatives of NASA, North American Rockwell, and Northrop participating. The failure of the drogue, being tested for the first time, was determined to be a result of the failure of the reefing ring attachment to the canopy skirt. The reason the ring attachment failed seemed to be lack of a good preflight load analysis and an error in the assumption used to determine the load capacity of the attachment. The failure of the deployment of the emergency system was still being investigated.
Apollo 4 (AS-501) was launched in the first all-up test of the Saturn V launch vehicle and also in a test of the CM heatshield. The Saturn V, used for the first time, carried a lunar module test article (LTA-10R) and a Block I command and service module (CSM 017) into orbit from KSC Launch Complex 39, Pad A, lifting off at 7:00:01 a.m. EST - one second later than planned. The launch was also the first use of Complex 39. The spacecraft landed 8 hours 37 minutes later in the primary recovery area in the Pacific Ocean, near Hawaii, about 14 kilometers from the planned point (30.06 N 172.32 W). CM, apex heatshield, and one main parachute were recovered by the carrier U.S.S. Bennington
Main objectives of the mission were to demonstrate the structural and thermal integrity of the space vehicle and to verify adequacy of the Block II heatshield design for entry at lunar return conditions. These objectives were accomplished.
The S-IC stage cutoff occurred 2 minutes 30 seconds into the flight at an altitude of about 63 kilometers. The S-II stage ignition occurred at 2 minutes 32 seconds and the burn lasted 6 minutes 7 seconds, followed by the S-IVB stage ignition and burn of 2 minutes 25 seconds. This series of launch vehicle operations placed the S-IVB and spacecraft combination in an earth parking orbit with an apogee of about 187 kilometers and a perigee of 182 kilometers. After two orbits, which required about three hours, the S-IVB stage was reignited to place the spacecraft in a simulated lunar trajectory. This burn lasted five minutes. Some 10 minutes after completion of the S-IVB burn, the spacecraft and S-IVB stage were separated, and less than 2 minutes later the service propulsion subsystem was fired to raise the apogee. The spacecraft was placed in an attitude with the thickest side of the CM heatshield away from the solar vector. During this four-and-one-half-hour cold-soak period, the spacecraft coasted to its highest apogee - 18,256.3 kilometers. A 70 mm still camera photographed the earth's surface every 10.6 seconds, taking 715 good-quality, high-resolution pictures.
About 8 hours 11 minutes after liftoff the service propulsion system was again ignited to increase the spacecraft inertial velocity and to simulate entry from a translunar mission. This burn lasted four and one half minutes. The planned entry velocity was 10.61 kilometers per second, while the actual velocity achieved was 10.70.
Recovery time of 2 hours 28 minutes was longer than anticipated, with the cause listed as sea conditions - 2.4-meter swells.
An Apollo drop test failed at El Centro, Calif. The two-drogue verification test had been planned to provide confidence in the drogue chute design (using a weighted bomb) before repeating the parachute test vehicle (PTV) test. Preliminary information indicated that in the test one drogue entangled with the other during deployment and that only one drogue inflated. The failure appeared to be related to a test deployment method rather than to drogue design. The test vehicle was successfully recovered by a USAF recovery parachute-intact and reusable.
A Parachute Test Vehicle (PTV) test failed at El Centro, Calif. The PTV was released from a B-52 aircraft at 15,240 meters and the drogue chute programmer was actuated by a static line connected to the aircraft. One drogue chute appeared to fail upon deployment, followed by failure of the second drogue seven seconds later. Disreefing of these drogues normally occurred at 8 seconds after deployment with disconnect at deployment at plus 18 seconds. The main chute programmer deployed and was effective for only 14 out of the expected 40 seconds' duration. This action was followed by normal deployment of one main parachute, which failed, followed by the second main parachute as programmed after four-tenths of a second, which also failed. The main chute failure was observed from the ground and the emergency parachute system deployment was commanded but also failed because of high dynamic pressure, allowing the PTV to impact and be destroyed. Investigation was under way and MSC personnel were en route to El Centro and Northrop-Ventura to determine the cause and to effect a solution.
Eberhard Rees, Apollo Special Task Team chief at North American Rockwell, participated in a failure review at Northrop-Ventura of the recent parachute test failure and in development of a revised test plan. Others at the review included Dale Myers and Norman Ryker from North American and W. Gasich and W. Steyer, General Manager and Apollo Program Manager at Northrop-Ventura. Those at the review put together a revised drop test program that resulted in only a two-week schedule delay because of the failure. Repair of the parachute test vehicle was under way. Meantime, tests would continue, employing bomb and boilerplate devices. Also, Rees decided to establish a Flight Readiness Review Board (headed by Joseph Kotanchik of MSC) to approve each drop test, and Northrop officials had established an internal review board to review test engineering and planning and were tightening their inspection and quality control areas.
Eberhard F. M. Rees, head of the Apollo Special Task Team at North American Rockwell, met with Kenneth S. Kleinknecht, MSC, and Martin L. Raines, Manager of the White Sands Test Facility, to review the team's recent operations and the responses of North American and its numerous subcontractors to the team's recommendations. Kleinknecht listed what he thought were the chief problems facing the CSM program: the S-band highgain antenna (which he said should be turned over entirely to the task team for resolution); the parachute program; the environmental control system; and contamination inside the spacecraft. He urged that the team take the lead in developing solutions to these problems.
MSC CSM Manager Kenneth S. Kleinknecht, in a letter to North American Rockwell's Dale D. Myers, protested lack of North American reponse to written MSC direction concerning parachute test vehicles. Kleinknecht pointed out that MSC had "considerably modified our usual requirements in supporting the boilerplate 19 task being performed for you by Western Ways, Inc. These efforts seem to be completely negated by delayed go-ahead to Northrop Ventura for their portion of the task. I understand that neither Western Ways nor Northrop Ventura was given a go-ahead until January 19, 1968. The original written direction to NR [North American] was on November 9, 1967, to provide another parachute test vehicle (PTV) and give us an estimate of cost and schedule for another boilerplate PTV." If the effort on the PTV had started at that time, "we would now be able to use that vehicle rather than the bomb-type vehicles after losing PTV No. 2. The cost and schedule for boilerplate 19 was not submitted to MSC until later, on December 22, asking for a reply by January 2, 1968. Because of the holiday period, this written reply was furnished on January 5, after an investigation of the cost and schedule. The Engineering Change Proposal [ECP] stated a completion date of May 5; however, after a request by my people to see what could be done to improve this date, the improvement moved the Northrop Ventura schedule from June 14 to May 24 [a Friday]. This date is three weeks later than the date cited in the ECP and is completely unacceptable. . . ."
On February 29, Myers assured Kleinknecht that North American had proceeded with the BP-19A task in advance of NASA full coverage. Initial partial coverage was issued to North American on January 5, 1968. On March 14, in a letter of commendation, Kleinknecht thanked Myers for the attention given the BP-19A effort that made a March 15 completion by Western Ways possible. On May 27, W. H. Gray, RASPO Manager, wrote another letter of commendation thanking North American for completing BP-19A in time for a drop test in May 1968.
Apollo drogue chute test 99-5 failed at the El Centro, Calif., parachute facility. The drop was conducted to demonstrate the slight change made in the reefed area and the 10-second reefing cutter at ultimate load conditions. The 5,897-kilogram vehicle was launched from a B-52 aircraft at 10,668 meters and programmer chute operation and timing appeared normal. At drogue deployment following mortar activation, one drogue appeared to separate from the vehicle. This chute was not recovered but ground observers indicated the failure seemed to occur in the riser or vehicle attachment. The second drogue remained on the vehicle but seemed to slip in the reefed state. This chute was recovered and inspection confirmed the canopy failure. The Air Force parachute system which was to recover the vehicle also failed in the reefed state.
Apollo 6 (AS-502) was launched from Complex 39A at Kennedy Space Center. The space vehicle consisted of a Saturn V launch vehicle with an unmanned, modified Block I command and service module (CSM 020) and a lunar module test article (LTA-2R).
Liftoff at 7:00 a.m. EST was normal but, during the first-stage (S-IC) boost phase, oscillations and abrupt measurement changes were observed. During the second-stage (S-II) boost phase, two of the J-2 engines shut down early and the remaining three were extended approximately one minute to compensate. The third stage (S-IVB) firing was also longer than planned and at termination of thrust the orbit was 177.7 x 362.9 kilometers rather than the 160.9-kilometer near-circular orbit planned. The attempt to reignite the S-IVB engine for the translunar injection was unsuccessful. Reentry speed was 10 kilometers per second rather than the planned 11.1, and the spacecraft landed 90.7 kilometers uprange of the targeted landing point.
The most significant spacecraft anomaly occurred at about 2 minutes 13 seconds after liftoff, when abrupt changes were indicated by strain, vibration, and acceleration measurements in the S-IVB, instrument unit, adapter, lunar module test article, and CSM. Apparently oscillations induced by the launch vehicle exceeded the spacecraft design criteria.
The second-stage (S-II) burn was normal until about 4 minutes 38 seconds after liftoff; then difficulties were recorded. Engine 2 cutoff was recorded about 6 minutes 53 seconds into the flight and engine 3 cutoff less than 3 seconds later. The remaining second-stage engines shut down at 9 minutes 36 seconds - 58 seconds later than planned.
The S-IVB engine during its first burn, which was normal, operated 29 seconds longer than programmed. After two revolutions in a parking orbit, during which the systems were checked, operational tests performed, and several attitude maneuvers made, preparations were completed for the S-IVB engine restart. The firing was scheduled to occur on the Cape Kennedy pass at the end of the second revolution, but could not be accomplished. A ground command was sent to the CSM to carry out a planned alternate mission, and the CSM separated from the S-IVB stage.
A service propulsion system (SPS) engine firing sequence resulted in a 442-second burn and an accompanying free-return orbit of 22,259.1 x 33.3 kilometers. Since the SPS was used to attain the desired high apogee, there was insufficient propellant left to gain the high-velocity increase desired for the entry. For this reason, a complete firing sequence was performed except that the thrust was inhibited.
Parachute deployment was normal and the spacecraft landed about 9 hours 50 minutes after liftoff, in the mid-Pacific, 90.7 kilometers uprange from the predicted landing area (27.40 N 157.59 W). A normal retrieval was made by the U.S.S. Okinawa, with waves of 2.1 to 2.4 meters.
The spacecraft was in good condition, including the unified crew hatch, flown for the first time. Charring of the thermal protection was about the same as that experienced on the Apollo 4 spacecraft (CM 017).
Of the five primary objectives, three - demonstrating separation of launch vehicle stages, performance of the emergency detection system (EDS) in a close-loop mode, and mission support facilities and operations - were achieved. Only partially achieved were the objectives of confirming structure and thermal integrity, compatibility of launch vehicle and spacecraft, and launch loads and dynamic characteristics; and of verifying operation of launch vehicle propulsion, guidance and control, and electrical systems. Apollo 6, therefore, was officially judged in December as "not a success in accordance with . . . NASA mission objectives."
ASPO Manager George M. Low informed Apollo Program Director Samuel C. Phillips of recent MSC work on the effects of launch vehicle-induced oscillations - i.e., "pogo" vibrations - on the spacecraft and its subsystems. MSC had made two key personnel assignments in this area:
MSC and North American Rockwell reached agreement on certification reviews for parachute packers in the Apollo program. The certification was effective for all parachute packers not previously certified, with upgrading of packers and recertification of present Apollo packers when required.
A tank cart at the San Diego Naval Air Station, defueling the Apollo 16 command module after its April 27 return from its mission to the moon, exploded because of overpressurization. Forty-six persons suspected of inhaling of toxic fumes, were hospitalized, but examination revealed no symptoms of inhalation. An Apollo 16 Deactivation Investigation Board completed its report on the accident June 30. The ratio of neutralizer to oxidizer being detanked had been too low because of the extra oxidizer retained in the CM tanks as a result of the Apollo 15 parachute anomaly. Changes were made in ground support equipment and detanking procedure to prevent future overpressurization.