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Charles W. Frick, Manager of the MSC Apollo Spacecraft Project Office, together with Maxime A. Faget, Charles W. Mathews, Christopher C. Kraft, Jr., John B. Lee, Owen E. Maynard, and Alan B. Kehlet of MSC and George M. Low of the NASA Office of Manned Space Flight, visited NAA at Downey, Calif. This was the first monthly meeting of the Apollo design and review team to survey NAA's progress in various areas, including the Apollo spacecraft heatshield, fuel cells, and service module.
NAA studies resulted in significant changes in the command module environmental control system (ECS).
NAA evaluated the possibility of integrating the fuel cell and environmental control system heat rejection into one system. The integrated system proved to be unsatisfactory, being 300 pounds heavier and considerably more complex than the two separate systems. A preliminary design of separate fuel cell radiators, possibly located on the service module, was started by NAA.
MSC reported that the three liquid-hydrogen-liquid-oxygen fuel cells would supply the main and emergency power through the Apollo mission except for the earth reentry phase. Two of the fuel cells would carry normal electrical loads and one would supply emergency power. Performance predictions had been met and exceeded in single-cell tests. Complete module tests would begin during the next quarter. The liquid-hydrogen liquid-oxygen reactants for the fuel cell power supply were stored in the supercritical state in spherical pressure vessels. A recent decision had been made to provide heat input to the storage vessels with electrical heaters rather than the water-glycol loop. Three zinc-silver oxide batteries would supply power for all the electrical loads during reentry and during the brief periods of peak loads. One of the batteries was reserved exclusively for the postlanding phase. Eagle Picher Company, Joplin, Mo., had been selected in August as subcontractor for the batteries.
The first fuel cell module delivered by Pratt and Whitney Aircraft to North American was started and put on load. The module operated normally and all test objectives were accomplished. Total operating time was four hours six minutes, with one hour at each of four loads-20, 30, 40, and 50 amperes. The fuel cell was shut down without incident and approximately 1,500 cubic centimeters (1.6 quarts) of water were collected.
North American conducted three tests (4, 20, and 88 hours) on the CSM fuel cell. The third ended prematurely because of a sudden drop in output. (Specification life on the modules was 100 hours.)
During this same week, Pratt and Whitney Aircraft tested a LEM-type fuel cell for 400 hours without shutdown and reported no leaks.
Joseph G. Thibodaux, Jr., MSC Propulsion and Power Division, reported at an Apollo Engineering and Development technical management meeting that the first J-2 firing of the service propulsion system engine was conducted at White Sands Missile Range (WSMR). Two fuel cell endurance tests of greater than 400 hours were completed at Pratt and Whitney. MSC would receive a single cell for testing during the month.
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.
The net effect of a decision by ASPO Manager Joseph F. Shea in May was that the total fuel cell effort at both Pratt and Whitney and North American should be no more than $9.7 million during FY 1966. The decision as to the distribution of the funds was left to the discretion of the fuel cell subsystem manager.
The first fuel cell system test at White Sands Test Facility was conducted successfully. Primary objectives were: 1 to verify the capability of the ground support equipment and operational checkout procedure to start up, operate, and shut down a single fuel cell power plant; and 2 to evaluate fuel cell operations during cold gimbaling of the service propulsion engine.
NASA Apollo Program Director Samuel C. Phillips indicated his concern to MSC over the extensive damage to a number of fuel cell modules from operational errors during integrated system testing. Phillips pointed out that in addition to the added cost there was a possible impact on the success of the flight program. He emphasized the importance of standardizing the procedures for fuel cell activation and shutdown at North American Aviation, MSC, and KSC to maximize learning opportunities.
George M. Low told Joseph N. Kotanchik, Chief of MSC's Structures and Mechanics Division, that actions were pending on Pratt & Whitney pressure vessel failures. The pressure vessels were used in the Apollo fuel cell system. Kotanchik had spelled out a list of problem areas in connection with both the vessels and management interface between MSC and principal contractor North American Aviation, and between North American and its subcontractor Pratt & Whitney.
Apollo 13 (AS-508) was launched from Pad A, Launch Complex 39, KSC, at 2:13 p.m. EST April 11, with astronauts James A. Lovell, Jr., John L. Swigert, Jr., and Fred W. Haise, Jr., aboard. The spacecraft and S-IVB stage entered a parking orbit with a 185.5-kilometer apogee and a 181.5-kilometer perigee. At 3:48 p.m., onboard TV was begun for five and one-half minutes. At 4:54 p.m., an S-IVB burn placed the spacecraft on a translunar trajectory, after which the CSM separated from the S-IVB and LM Aquarius. (The crew had named lunar module 7 Aquarius and CSM 109 Odyssey.) The CSM then hard-docked with the LM. The S-IVB auxiliary propulsion system made an evasive maneuver after CSM/LM ejection from the S-IVB at 6:14 p.m. The docking and ejection maneuvers were televised during a 72-minute period in which interior and exterior views of the spacecraft were also shown.
At 8:13 p.m. EST a 217-second S-IVB auxiliary propulsion system burn aimed the S-IVB for a lunar target point so accurately that another burn was not required. The S-IVB/IU impacted the lunar surface at 8:10 p.m. EST on April 14 at a speed of 259 meters per second. Impact was 137.1 kilometers from the Apollo 12 seismometer. The seismic signal generated by the impact lasted 3 hours 20 minutes and was so strong that a ground command was necessary to reduce seismometer gain and keep the recording on the scale. The suprathermal ion detector experiment, also deployed by the Apollo 12 crew, recorded a jump in the number of ions from zero at the time of impact up to 2,500 shortly thereafter and then back to a zero count. Scientists theorized that ionization had been produced by 6,300 K to 10,300 K (6,000 degrees C to 10,000 degrees C) temperature generated by the impact or that particles had reached an altitude of 60 kilometers from the lunar surface and had been ionized by sunlight.
Meanwhile back in the CSM/LM, the crew had been performing the routine housekeeping duties associated with the period of the translunar coast. At 30:40 ground elapsed time a midcourse correction maneuver took the spacecraft off a free-return trajectory in order to control the arrival time at the moon. Ensuring proper lighting conditions at the landing site. The maneuver placed the spacecraft on the desired trajectory, on which the closest approach to the moon would be 114.9 kilometers.
At 10:08 p.m. EST April 13, the crew reported an undervoltage alarm on the CSM main bus B, rapid loss of pressure in SM oxygen tank No. 2, and dropping current in fuel cells 1 and 3 to a zero reading. The loss of oxygen and primary power in the service module required an immediate abort of the mission. The astronauts powered up the LM, powered down the CSM, and used the LM systems for power and life support. The first maneuver following the abort decision was made with the descent propulsion system to place the spacecraft back in a free-return trajectory around the moon. After the spacecraft swung around the moon, another maneuver reduced the coast time back to earth and moved the landing point from the Indian Ocean to the South Pacific.
About four hours before reentry on April 17, the service module was jettisoned and the crew took photographs and made visual observations of the damaged area. About one hour before splashdown the command module was powered up and the lunar module was jettisoned. Parachutes were deployed as planned, and the Odyssey landed in the mid-Pacific 6.4 kilometers from the recovery ship U.S.S. Iwo Jima at 1:07 p.m. EST April 17. The astronauts were picked up by helicopter and transported to the recovery ship less than an hour after splashdown.
Official NASA Account of the Mission from Where No Man Has Gone Before: A History of Apollo Lunar Exploration Missions, by W. David Compton, published as NASA SP-4214 in the NASA History Series, 1989.
Almost lost in the drama of the mission was the one piece of scientific information that Apollo 13 was able to provide. Shortly after command module pilot Jack Swigert had extracted the lunar module from atop the S-IVB stage, ground controllers fired the auxiliary propulsion system on the big rocket, putting it on a course to crash into the moon. Three days later the 30,700-pound (13,925 kilogram) hulk struck the lunar surface at 5,600 miles per hour (2.5 kilometers per second) some 74 miles (119 kilometers) west-northwest of the Apollo 12 landing site, releasing energy estimated as equivalent to the explosion of 7.7 tons (7,000 kilograms) of TNT. Half a minute later the passive seismometer left by Apollo 12 recorded the onset of vibrations that persisted for more than four hours. Another instrument, the lunar ionosphere detector, sensed a gas cloud that arrived a few seconds before the seismic signal and lasted for more than a minute. Seismologists were baffled by the moon's response to shock, but welcomed the new means of generating data.
In the year that it took to discover and correct the cause of the Apollo 13 failure, the scope of the remaining missions was altered. Apollo 14 would visit the site intended for exploration by Apollo 13, but it would go there as the last of the intermediate exploration missions.
To support the Apollo 13 Review Board, an MSC Apollo 13 Investigation Team, headed by Scott H. Simpkinson, was established with the following panels: spacecraft incident investigation, flight crew observations, flight operations and network ; photograph handling, processing, and cataloging ; corrective action study and implementation for the CSM, LM, and government-furnished equipment; related system evaluation; reaction processes in high-pressure fluid systems; high-pressure oxygen system survey; public affairs; and administration, communications, and procurement.
MSC Director Robert R. Gilruth reported MSC actions on the Apollo 13 Review Board recommendations, including: