With the arrival of Apollo 12’s spacecraft in late March 1969, four months before the first moon landing, Kennedy Space Center again had three Apollos in the operational flow. On 30 April Grumman mated the lunar module ascent and descent stages, while North American readied the command-service module for a cabin leak test in the altitude chamber. Launch vehicle stacking awaited the arrival of the S-IC first stage, which arrived from Michoud on 3 May and was placed on mobile launcher 2 four days later. Operations on Apollo 12 halted for two days while ordnance was installed in Apollo 11. The remaining Saturn stages were erected on the 22nd. At the operations and checkout building, a number of hardware problems delayed operations by a week. Although the Launch Operations office postponed until 30 June the transfer of the spacecraft to the vehicle assembly building, the launch team continued under a tight schedule. If Apollo 11 failed, KSC faced a possible September launch for Apollo 12.¹

Testing went well during the next six weeks and the space vehicle stack was complete by 1 July. The successful lunar landing later that month relaxed the pace. After the splashdown on the 24th, General Phillips announced a 14 November launch of Apollo 12 to the moon’s Ocean of Storms. Among the mission goals, NASA hoped to improve its landing techniques and secure low-orbit photographs of sites for further exploration. During extra-vehicular periods, the astronauts would gather lunar samples and deploy the first Apollo lunar surface experiments package.²

With the accomplishment of Apollo’s primary objective, a number of key program officials decided to move elsewhere. In August 1969 Phillips left his position as Apollo Program Director to command the USAF Space and Missile Systems Organization. Rocco Petrone moved up from KSC to fill the vacancy in the Office of Manned Space Flight. The following month Rear Admiral Roderick O. Middleton vacated the Apollo Program Manager’s Office at KSC to assume command of Cruiser-Destroyer Flotilla 12. In December Dr. George Mueller resigned as NASA’s Associate Administrator for Manned Space Flight and was replaced by Dale Myers, an executive from North American Rockwell. That same month Albert Siepert announced his retirement from KSC.³

Petrone’s departure from KSC brought Walter J. Kapryan to the post of Director of Launch Operations. A native of Flint, Michigan, and a graduate of Wayne State University, Kapryan had served as a B-29 flight engineer in World War II. In 1947 he had entered the field of hydrodynamic research at Langley Research Center in Virginia. When NASA absorbed Langley, Kapryan became a member of the Space Task Group. He came to the Cape in 1960 as a project engineer for Mercury-Redstone, worked for a time in Houston, and then headed Houston’s Gemini Program Office in Florida. Kapryan came to Apollo in late 1966, first as Assistant Apollo Spacecraft Program Manager and then as Petrone’s deputy. Although less imposing physically and less assertive in manner than Petrone, Kapryan enjoyed wide respect within Apollo program ranks. Middleton’s successor, Edward R. Mathews, was a veteran of the Missile Firing Laboratory. As Chief of the Saturn IB Systems Office, Mathews had played an important role in LC-34 and 37 modifications. He had served as Deputy Apollo Program Manager since September 1967. Siepert’s duties as Deputy Director for Center Management were taken on by Miles Ross when the latter became Deputy Center Director in June 1970. Fortunately there was little turnover during the remainder of the program.⁴

Apollo 12 rolled out in the early daylight of 8 September. The prime crew for the mission - Commander Charles Conrad, Command Module Pilot Richard Gordon, and Lunar Module Pilot Alan Bean - joined hundreds of other spectators. During September and October, the checkout proceeded in routine fashion. In the local jargon, it was a nominal operation. The countdown demonstration test ended on 29 October without incident, although rain and high winds stormed through the complex at simulated liftoff.⁵

The launch team started precount procedures one week before launch day. The 70 hours of activities moved along smoothly until Wednesday, 12 November. That morning technicians began filling the service module’s liquid hydrogen tanks, which fed gaseous hydrogen to the spacecraft’s fuel cells. There the hydrogen mixed with oxygen to provide electrical power and drinking water. Within minutes the North American test team knew it had a problem: one tank was not chilling down. When the team stopped the hydrogen flow, the fuel level dropped off rapidly. A crew member, looking through a panel window, detected frost on the tank. It was found that a leak in the outer shell had destroyed the vacuum insulation. Less than 40 hours remained on the countdown clock, and the problem was a new one for the North American crew at Merritt Island. After consulting with the Manned Spacecraft Center, John Williams, Spacecraft Operation Director, decided to replace the faulty tank with its corresponding unit from Apollo 13. Judging from experience at Downey, there was ample time for the operation. If the replacement could not be accomplished within the remaining hold time, KSC would delay the launch one month. The exchange involved removing an access panel and the cryogenic service lines leading through the panel, disconnecting a series of cryogenic feed lines and electrical connections between the tank and the hydrogen subsystem shelf, exchanging tanks, and refastening all the parts. The North American crew worked deliberately since spacecraft power was on, but still managed to complete the work within 24 hours. Meanwhile Launch Operations rescheduled the spacecraft cryogenic loading for Thursday morning at T-17 hours.⁶

The launch team had planned one other major change in the countdown - the installation of the fuel capsule that would provide power for the package of experiments to be left on the lunar surface. The experimental instruments received power from a small (45 centimeters high, 40 centimeters in diameter) atomic generator. The 3.8 kilograms of plutonium 238 that fueled the generator rode to the moon inside a graphite cask. Understandably, the plutonium was one of the last items placed aboard.⁷

Lightning Strikes

Scattered rain showers, forerunners of a cold front, marked the approach of Apollo 12’s launch day. A broad band of clouds and precipitation, punctuated by numerous thunderstorms, moved into central Florida on Thursday afternoon. By nightfall, the thunderstorms ended and the rain slackened. The next morning, radar displays of precipitation echoes placed the cold front about 80 miles north of the Cape. Despite the weather, large crowds were on hand to watch the liftoff. President and Mrs. Nixon headed the list of 3,000 guests, marking the first and only appearance of a Chief Executive at an Apollo launch. Other names on the VIP list included Vice President Agnew, Henry Kissinger, Roy Disney, Jr. (of Walt Disney Productions), Arnold Palmer, and James Stewart.⁸

As the space vehicle underwent final preparations, the approaching cold front pushed large banks of clouds toward the Cape. Cold rain drenched the spectators. Up in the command module, Yankee Clipper, Commander Conrad noticed water leaking between the boost protective cover and the spacecraft. He later recalled:

I could see water on my two windows - window 1 and 2. We experienced varying amounts passing across these windows, dependent on how heavily it was raining. These [rain and wind] were the only things noted up to liftoff.⁹

With a half hour to go, Merritt Island was experiencing peak winds of 14 knots, light rain showers, broken clouds at 240 meters, and overcast skies at 3,000 meters. But the ceiling exceeded the minimum requirement of 150 meters, and the ground winds were within limits. The Apollo design permitted launch during rain. The possibility of lightning concerned Launch Operations Director Kapryan, however, and he considered a hold. As he explained at the postlaunch briefing:

We were within our minimums. . . . The only consideration as far as launching under what apparently are adverse conditions - they are really twofold. Number 1, we would not launch into a thundercloud; number 2, we would not launch when we had lightning in the system. There was some concern. We had very unpredictable weather predictions. The weather was deteriorating. . . .¹⁰

A weather report from the Eastern Test Range helped Kapryan make up his mind. An Air Force plane reported only mild turbulence and no indication of lightning within 32 kilometers of LC-39. Air Force 1, bringing the President to the launch, experienced no turbulence while flying through the front. Astronauts Slayton and Stafford told Kapryan the weather was satisfactory. The launch operations director also had to weigh a “now or scrub” situation: the liquid oxygen replenish pump had failed at T-1 hour and 22 minutes, and everything depended on a backup pump. With the launch rules and available evidence giving him an affirmative, Kapryan opted for an 11:22 a.m.^* launch.¹¹

Apollo 12 lifted off on schedule. Thirty-six seconds later, as the space vehicle reached 2,000 meters, spectators observed two parallel streaks of lightning flash toward the launch pad. The Yankee Clipper experienced a power failure. As Conrad later recalled:

I was aware of a white light. I knew that we were in the clouds; and although I was watching the gauges I was aware of a white light. The next thing I noted was that I heard the master alarm ringing in my ears and I glanced over to the caution and warning panel and it was a sight to behold.¹²

The spacecraft sustained a second lightning discharge 16 seconds later at an altitude of 4,400 meters. Conrad reported to Mission Control: “We just lost the [stabilizing] platform, gang: I don’t know what happened here; we had everything in the world drop out."¹³ Fortunately, the spacecraft automatically switched to a backup power source, and the astronauts soon restored primary power.

That Apollo 12 had been hit by lightning was a matter of dispute for some time. At the postlaunch briefing, one hour after liftoff, reporters asked Stafford, Apollo 10 commander, and Kapryan about reports of lightning. Stafford dismissed the reports as only speculation. Kapryan said, “I think we’re pretty certain that it was not lightning. If the vehicle had been struck by lightning the damage would have been quite severe rather than a momentary dropout.” When reporters pressed the matter, Stafford and Kapryan responded that NASA had quite a few people watching after liftoff and no one reported a sighting. Subsequently, the lightning reports from numerous viewers were substantiated by space vehicle data and KSC cameras.¹⁴

President Nixon chose not to mention the incident in his postlaunch remarks at the launch control center. He commented on the “great experience and awe” of an Apollo launch. He repeated the remarks made to him by astronauts “that those on the ground, the engineers, and the technicians, and the scientists, and all of those who work in the program, that they are really the heart of this great, successful experience for the American people and for all the people of the world."¹⁵ Nixon promised to keep the United States first in space.

After the unnerving lightning incident, the mission moved smoothly. Apollo 12 went into earth orbit 11 minutes and 43 seconds after liftoff. By 2:15 p.m., it had accelerated to 38,000 kilometers an hour and was headed for the moon. There was a significant change in the trajectory. Three earlier Apollos flew a course that permitted looping the moon and returning to earth if the spacecraft failed to attain lunar orbit. Apollo 12, by a midcourse maneuver, entered a trajectory that did not allow free return. This was necessary to reach the desired landing site.

On 19 November 1969, Conrad and Bean landed in the Ocean of Storms, within 180 meters of the unmanned Surveyor 3 that had been there for two years. The two astronauts spent 7 hours and 45 minutes on the lunar surface, setting up scientific instruments, collecting pieces from the Surveyor, gathering materials, and photographing the landing craft, the Surveyor, and other objects of interest. They lifted off on the morning of 20 November and splashed down in the South Pacific on 24 November.¹⁶

With plans afoot for a world tour, the crew first returned to KSC on 17 December for a reunion with the launch team. Debus led them into the transfer aisle of the vehicle assembly building as a Navy band played “Anchors Aweigh” and 8,000 members of the government-industry team applauded. He complimented the crew on leaving as commanders and returning as U.S. Navy captains.

"The crew didn’t consider the flight over until we got back here,” Conrad said. “We forgive the weather man for his job, but had we to do it again, I’d launch exactly under the same conditions.” Gordon pointed out that

the real guts of these flights, after their formative, opening stages, are really put together here. The hardware is brought here, it’s mated here in the VAB, and a great amount of testing is done. But more importantly, the crew is here most of the months before launch. And this is really the way it ought to be. This is really our home.¹⁷

The astronauts received enlarged color photographs of the Apollo 12 liftoff, plus a stone from the crawlerway over which their vehicle began its journey. Then they walked through cheering crowds along the transfer aisle, exchanging handshakes and signing autographs. They lunched with the KSC Management Council and contractor managers where they regaled the party with some lighthearted comments about their achievement. The astronauts were presented with such trinkets as whiskbrooms to remove lunar dust, tiny parasols to ward off the intense sunlight on the moon, and joke books to while away the time on lunar journeys. It was a happy family reunion.¹⁸

Whys and Wherefores of Lightning

The strike on Apollo 12 led to another study of lightning protection, this one focusing on the atmospheric conditions that might threaten a launch. At a meeting of the American Geophysical Union in December 1969, experts discussed the incident and offered NASA some observations. The scientists generally agreed that Apollo 12 triggered the lightning discharges. There were no other signs of lightning or thunder for six hours before and six hours after the launch. However, readings on electrical field meters in the Cape area indicated disturbed weather conditions. Apparently Apollo 12 had entered an electrical cloud and distorted the field sufficiently for breakdown to occur. The 110-meter space vehicle and its 500-meter ionized exhaust plume then formed an excellent conductor. The space vehicle had probably triggered a lightning stroke from an electrified cloud incapable of producing lightning on its own. Although the launch vehicle’s design incorporated safeguards against electrical discharges, lightning could damage components in the spacecraft such as solid-state electronic devices. The Apollo 12 experience prompted NASA officials to reexamine the space vehicle and the weather criteria for a launch.¹⁹

The lightning investigation team opposed any modifications to the spacecraft. They recommended, instead, further launch restrictions to reduce the possibility of touching off another lightning strike. The new “severe weather restrictions” appeared in the launch rules for Apollo 13. The space vehicle would not be launched if the nominal flight path would carry the vehicle within 8 kilometers of a thunderstorm, through cold-front or squall-line clouds, or through cumulus clouds with tops at 3,050 meters or higher.²⁰ The additional weather limitations would have a moderate effect on winter and spring launchings; in those seasons, high winds would more often cause delays. On a February afternoon, the probability of delay would increase from 10% to 18% with the new restrictions. In the summer, the probability of a scrub would jump from 3% to 18%. Despite the new rules, the odds for acceptable weather were still better than nine out of ten for most three-hour launch windows.²¹

Apollo 13 Launch Operations

The launch vehicle and spacecraft for the Apollo 13 mission arrived at KSC in June 1969. Following the Apollo 11 success, NASA set a March 1970 launch date for Apollo 13. More planning time was added in January, moving the launch to 11 April. Prelaunch operations went smoothly through the fall and winter months. The work in high bay 1 marked its last use for Apollo; subsequently the area would be used for Skylab operations. The Bendix crawler team transferred the space vehicle to pad A on 15 December. The flight readiness test, scheduled before the January program change, was run on 29 January as a “confidence test” and rerun on 26 February. After four days of hypergolic load tests in mid-March, the launch team began the countdown demonstration test on the 18th.²²

A strange accident punctuated the last day of the test. Early on 25 March, Graydon Corn’s propellants crew started the chill-down of the LOX pumping system. The operation required a 760-liter-per-minute flow to the replenishing pumps (which could handle five times that rate) and a lesser amount through a bleed line that had been added to the LOX system after the 500-F spill in August 1966. [see chapter 15-9] During the 40 minutes of precooling, the launch team emptied 39,000 liters of LOX into a drainage ditch outside the perimeter fence. Normally ocean breezes dissipated the oxygen fog. On the morning of the 25th, however, there was no wind and a pronounced temperature inversion. A dense fog built up in the drainage ditch; at a culvert where the road to the slide wire bunker crossed the ditch, the invisible oxygen overflowed onto the bank. At 6:00 a.m. the closeout crew and safety personnel left the LOX storage area. First-stage loading could begin after a three-minute chill-down of the 38,000-liter-per-minute main pumps. A security team completed its job of clearing the pad area and proceeded in three cars to the perimeter gate southwest of the LOX sphere. The driver of the first car, Patrolman Nolan Watson, drove through the gate and parked. As he walked back to Earl Paige’s car, an order over the radio directed the team to clear the slide wire bunker area. Paige turned his ignition on and heard a loud pop. Soon flames sprang up from beneath the hood. Watson ran back to his car, only to find it also on fire. About the same time, the third car burst into flames. The three guards quickly ran for cover. A fire and rescue crew arrived in five minutes but took no action until the oxygen cloud dissipated. It was nearly 7:00 a.m. before the fire was under control, leaving three burnt hulks and a shaken crew.

Debus called for an immediate investigation. The preliminary report, rendered a week later, blamed the accident on the enriched oxygen atmosphere. Spontaneous ignition resulting from the engine heat, combustibles (oil and grease on the engine covers and gas around the carburetors) and the oxygen vapor cloud caused two of the fires, the third apparently starting when the driver turned the ignition switch. The report criticized the practice of dumping large quantities of cryogenics and termed the resulting vapor a hazard. Recommendations included immediate studies of the drainage system leading from the LOX storage area and its dump reservoir, of entry and exit routes at pad 39 A, and of KSC’s safety training course. The major change brought about by the accident was to extend the LOX drainage pipes beyond the perimeter ditch to a marshy area farther from the pad.²³

Another anomaly during the demonstration test appeared insignificant at the time; in fact, it was the beginning of what was to prove Apollo’s most nerve-wracking hours. On 24 March the North American launch crew finished loading the cryogenics into the service module. Tank testing had gone smoothly and nothing about the loading operation presaged troubles ahead. The first sign came when the launch crew partially emptied the two liquid oxygen tanks. While the first tank performed normally, emptying half of its contents, the second tank released only 8% of its LOX. The crew prepared an interim discrepancy report and postponed further action until the end of the demonstration test.

The spacecraft team resumed detanking operations on the 27th, after discussing the matter with Houston, Downey, and Beech Aircraft Corporation. The problem centered on a possible leak between the fill line and the quantity probe because of a loose fit in the sleeves and tube. A second failure of the detanking procedure strengthened this view. After additional attempts at higher pressures proved unsuccessful, the KSC team decided to “boil off” the remaining LOX. The tank heaters, energized by 65 volts of direct current, were turned on; 90 minutes later the tank fans were also activated. The solution proved to be a slow one. After 6 hours the quantity of LOX in the tank still stood at 35%. The team continued to run the heaters and began pressurizing the tank for a few minutes and then venting the fill line. After two more hours of alternately heating and venting, the tank emptied.

Apollo officials faced a difficult decision. Replacement of the oxygen shelf in the service module would take two days and posed the possibility of damaging other equipment. If the problem were a loose fill tube, the shortcoming would not threaten the mission. The LOX tank would still supply the fuel cells properly and any electrical short at the capacitance gauge would be insignificant. After further discussions with Washington, Houston, and Downey, KSC undertook a partial fill on the 30th. Both tanks reached the 20% level without any trouble, but emptying the second tank again required heating and pressure cycling. Apollo technical and management personnel weighed the possible hazards of flying with a loose fill tube against the problems of shelf replacement. The decision was to keep the defective tank.²⁴

A second cryogenic tank problem received more publicity in the closing days of the prelaunch operations. Liquid helium from a tank in the lunar module was used to assure a steady flow of propellants to the descent engine. The tank’s design allowed for a slow increase of pressure as the helium warmed, but during the countdown demonstration, pressure in the tank began rising too fast. If a faulty vacuum allowed heat to build up too rapidly, the increased pressure would blow the tank’s burst disk and prevent a lunar landing. Over the first weekend in April, newspapers reported the helium tank as a serious problem. A test conducted on Monday the 6th, however, indicated that the “heat rate loss was well within parameters and acceptable for launch.”²⁵

Apollo operations continued to attract famous people from around the world. In early March, French President and Mme. Pompidou spent a day at the center. The following week, 50 members of the U.S. Congress and the Canadian Parliament got a close view of Apollo 13; 60 German and Japanese astronomers visited Merritt Island on 9 March, after viewing a solar eclipse in north Florida. Later that month the British astronomer, Sir Bernard Lovell, and his wife were guests. The VIP list for the 11 April launch included Willy Brandt, Chancellor of West Germany, Vice President Agnew, and Secretary of State William Rogers.²⁶

A Case of Measles

Three notables in residence - the crew of commander James Lovell, command module pilot Thomas K. Mattingly, and lunar module pilot Fred Haise - kept busy in the simulators and altitude chambers. While Lovell and Haise trained for two moon walks, Mattingly studied his photographic assignments which included the moon, sun, and other astronomical subjects. Training went smoothly, the hectic pace of previous launches seemingly a thing of the past. The situation changed dramatically, however, when NASA’s Medical Director, Dr. Charles A. Berry, reported on 6 April that the prime crew had been exposed to measles. Backup lunar module pilot Charles Duke had a case of german measles (rubella) and Jeffrey Lovell, the commander’s son, was down with the red measles (rubeola). Although the three astronauts were in good physical condition, blood samples were taken to determine their immunity. Initial tests showed satisfactory antibody levels in all three astronauts, but a recheck cast doubts on Mattingly’s condition. Further tests indicated that Mattingly had no immunity and would likely experience the illness about the middle of the lunar mission.

At a press briefing on 8 April, Dr. Berry indicated that he would recommend against Mattingly’s flying. NASA’s preventive medicine program was questioned and Berry acknowledged the need to re-examine the subject. Previously crews had been restricted to essential contact during the last 21 days of prelaunch operations. This still included many people - training personnel, workers at the crew quarters, even younger members of the immediate families. The astronauts’ schedule kept them in KSC’s crew quarters much of the last three weeks, but risks were inevitable. Berry noted that some loopholes in the isolation program were necessary; others might be eliminated. He mentioned the likelihood of more antibody testing and immunization, even for such unlikely adult diseases as measles.²⁷

Mattingly’s health posed a difficult decision for NASA. Duke’s illness ruled out the substitution of the alternate crew. Delaying the launch a month would lessen confidence in the space vehicle and add $800,000 in costs. Another alternative was to replace Mattingly with his backup, John Swigert. The longer time between missions had permitted extensive simulator training with the backup crew. Although a late substitution for the other two crew members was out of the question, the command module pilot was more on his own. A last-minute switch might work. Thursday morning, 9 April, a new crew of Lovell, Haise, and Swigert entered the flight crew simulators.²⁸

The Flight Crew Operations Branch concentrated on situations that required rapid teamwork. First they tested the crew’s ability to handle various abort situations. Then the crew practiced the mission’s critical maneuvers: the translunar injection, transposition and docking, lunar orbital insertion, descent orbit insertion, rendezvous and docking, and transearth injection. Mechanical failures were cranked into each of the maneuvers, forcing Swigert to make corrections. One situation required a decision and response within two seconds.²⁹ The major concern was communications between crew members. As Riley McCafferty, branch chief, put it:

From the standpoint of putting these three guys together and these three guys accepting each other and these three guys establishing confidence in each other, that wasn’t our concern. Our concern was, did we have the proper communication, so when Jack Swigert said, “that’s good,” did they really know what “good” meant to Swigert versus what “good” meant to Mattingly?³⁰

The Flight Crew Operations Branch had striven for compatibility in training the prime and backup crews. With Apollo 13 came the first fruits of their labor. By Friday afternoon Deke Slayton and Riley McCafferty were convinced that Swigert could work with his new crew mates.

More important, Lovell was satisfied with the new arrangement. Paine, after discussing the matter with Lovell, Slayton, and other Apollo officials, gave the mission a go-ahead at KSC’s prelaunch press conference Friday afternoon. Paine told reporters there was never any question about Swigert’s ability as a command module pilot: “Jack literally wrote the book on the malfunctions and how to overcome them.” NASA’s concern had been whether the astronauts could work together effectively, and the 12 hours of intensive tests had removed all doubts. Slayton praised the crew training group: “They got the equipment on the line for the last 36 hours in A number 1 shape, came up with a beautiful plan, and we in fact did it. I guess we were all surprised also that the crew did integrate as well as they did.” A reporter asked whether the change had caused extra crew fatigue. Slayton noted that the tests had not exceeded the normal work schedule. If the crew had not been ready by Friday noon, NASA was prepared to postpone the launch.³¹

A Fragile Lifeboat

The Apollo 13 countdown proceeded without a major incident, and liftoff came at 2:13 p.m. on 11 April. When the S-II stage’s center engine shut down 132 seconds early, an extra 34-second burn from each of the four outboard engines made up most of the difference. An additional nine-second burn of the S-IVB stage brought the vehicle to within 0.4 meters/second of the planned velocity and left sufficient fuel to boost the space vehicle out of the earth’s gravitational field.³² Aside from the S-II problem, the first two days of the mission went according to plan. The crew started the third day in space by inspecting the lunar module. Lovell and Haise read a supercritical helium pressure well under the danger line. Fifty-five hours into the mission the crew began a television transmission from the command module, Odyssey. Fred Haise demonstrated movement through the tunnel into the lunar module, Aquarius, and remarked: “There’s a little bit of an orientation change that, even though I’d been through it once, in the water tank, is still pretty unusual. I find myself now standing with my head on the floor, when I get down into the LM.” For the next half hour the crew described their temporary quarters in a space version of “Person to Person.” The television interview ended on a light note as Lovell showed off a floating tape recorder. Musical selections included “Aquarius” from “Hair” and the theme from “2001, A Space Odyssey."³³

The good cheer came to a sudden end a few minutes later when the warning system indicated low pressure in hydrogen tank 1. Mission control asked the crew to turn on the cryogenic fans and heaters. Ninety seconds after the fans started up, Mission Control lost all telemetry for two seconds. The crew heard a loud “bang” and observed a low voltage condition on d.c. main bus B.^* Swigert reported, “Okay, Houston. Hey, we’ve got a problem here."³⁴ The full extent of the problem, however, was not immediately apparent. Voltage on main bus B recovered momentarily. The quantity gauge for oxygen tank 2 fluctuated and then returned to an off-scale high reading. Repeated firings of the attitude control thrusters on the service module added to the confusion. According to a later NASA report the thrusters were probably firing to overcome the effects of venting oxygen and a blown panel. Within minutes, the electrical output from fuel cells 1 and 3 dropped to zero. At first the mission controllers focused on the electrical systems, postulating a possible disconnect between the fuel cells and their respective buses. Upon realizing that the fuel cells were not working, mission control directed an emergency powerdown of the command module. With indications of a pressure loss in oxygen tank 1, Houston directed a switch in electrical power to obtain a reading from the number 2 tank’s instrumentation. The tank was empty. The reading substantiated a crew report that the spacecraft was venting something into space. As the pressure in oxygen tank 1 continued to drop, Lovell’s crew abandoned the mission and sought refuge in the lunar module.

A subsequent investigation pieced together the probable sequence of events. Apparently the start of the fans in oxygen tank 2 caused an electrical short circuit. Damaged Teflon insulation around the fan motor wires caught fire. Although the Teflon burned slowly, increasing heat and pressure soon ruptured the tank. The escaping oxygen either ignited with combustibles in the oxygen shelf compartment or blew an access panel off by itself. The panel struck the spacecraft high-gain antenna, disrupting telemetry signals momentarily. The pressure in oxygen tank 1 began dropping immediately after the telemetry loss. Apparently the same force that blew off the panel also damaged tank 1. The sudden and possibly violent failure of tank 2 may have broken a line to tank 1 or caused a valve to leak.³⁵

The plight of the astronauts reawakened world interest in the Apollo program. Television carried the drama to millions. Foreign countries offered their services for a recovery outside the intended Pacific splashdown area. At the manned spaceflight centers, concern was matched by a determination to return the astronauts safely. Two major activities dominated the remainder of the mission: planning and conducting the propulsion maneuvers with the lunar module so as to bring the spacecraft back to earth, and managing the vital resources - oxygen, water, electricity, and the canisters of lithium hydroxide used to remove carbon dioxide from the cabin atmosphere. Open communications lines between KSC and mission control at Houston carried advice and test requirements. The two centers simulated the various maneuvers and conservation measures before directions were given to the flight crew. A team under Charles Mars, lunar module project engineer, devised a means of recharging the command-service module’s re-entry batteries from the lunar module’s electrical system. Another KSC recommendation turned off the radar heaters to save electricity. North American and Grumman engineers at KSC helped devise ways to transfer water from the portable life support systems into the lunar module’s water coolant system. One of the biggest problems was the removal of carbon dioxide from the crowded Aquarius. KSC engineers, again duplicating activities at Houston, rigged a system that carried the CO₂-rich air from the lunar module, through a hose, into the command-service module’s lithium hydroxide canisters. Over in KSC’s flight crew training building, the Houston team simulated in advance the various situations to be encountered by the astronauts.³⁶

Apollo 13 looped around the moon on 14 April 1970. While the lunar module barely provided room to turn around, the crew preferred its narrow confines to the chilly 11 degrees C of the powerless command module. Respect for Aquarius increased as its systems continued to function well past their two day mission expectancy.³⁷ Splashdown came in the South Pacific on 17 April.

While the dramatic rescue earned plaudits for the entire Apollo team, the mission had failed. Paine took steps to determine the cause of the accident as the astronauts were returning to earth; on the 17th he announced the appointment of an Apollo 13 review board under the leadership of Langley Research Center’s Director, Edgar M. Cortright. The board conducted an intensive investigation during the next six weeks and the positive reception of its report contrasted sharply with the earlier Apollo fire investigation. The board concluded “that the accident was not the result of a chance malfunction in a statistical sense, but rather from an unusual combination of mistakes, coupled with a somewhat deficient and unforgiving design."³⁸

Oxygen tank 2 - the one that first ruptured - had undergone acceptance tests at the Beech Aircraft Corporation factory in 1967. The tank was installed in SM-106 (Apollo 10) and later removed for modifications. During the operation, the oxygen shelf was jarred and fell some 5 centimeters. North American officials analyzed the incident and concluded that there was no damage. The review board found the likelihood of tank damage from the incident “rather low,” but listed the accident as a possible cause of the loosefitting fill tube. The oxygen shelf was retested after the modifications, but no cryogenics were used. As the components worked satisfactorily, the shelf was installed in SM-109 (Apollo 13) on 22 November 1968.

Unfortunately, when the tank arrived at KSC in June 1969, it had an even more serious shortcoming. The two protective thermostatic switches on its heater were built to 1962 specifications for 28-volt d.c. power. In 1965 North American had issued a revised specification - the heaters would operate on 65 volts for tank pressurization. Beech did not change the thermostatic switches, and both North American and NASA documentation reviews overlooked the error. Subsequent qualification and acceptance tests did not require complete switch cycling, and so they too failed to reveal the incompatibility. During tank pressurization the 28-volt switches could accommodate the 65 volts from KSC’s ground support equipment because the thermostats remained cool and closed. However, if the tank temperature rose considerably, as it did for the first time during KSC’s special detanking, the 28-volt thermostatic switches would fail. When the switches started to open at their upper limit of 300 kelvins (27 degrees C) on 27 March, the current in the ground equipment welded them permanently closed. The review board estimated that, after the switches failed, temperatures in the tank reached 811 kelvins (538 degrees C) in spots during the eight hours of detanking. The intense heat would have severely damaged the Teflon insulation on the fan motor wires.

As the board indicated, the special detanking on 27 March 1970 did not violate KSC procedures. However, the launch team could have detected the failure of the thermostatic switches to open by observing heater current readings on the control panel. The tank temperatures indicated that the heaters had reached their temperature limit and a switch opening should follow. There was also an apparent communications gap while the oxygen tank problem was under debate. Attention focused on the loose fill tube, and many individuals at Houston, North American, and Beech were unaware of the extended heater operations. Those aware of the special detanking procedure failed to consider the damage that might result from the excessive heating and did not alert Apollo management to the possible consequences.³⁹

The board summed up the lesson of Apollo 13 in the preface to its report:

The total Apollo system of ground complexes, launch vehicle, and spacecraft constitutes the most ambitious and demanding engineering development ever undertaken by man. For these missions to succeed, both men and equipment must perform to near perfection. That this system has already resulted in two successful lunar surface explorations is a tribute to those men and women who conceived, designed, built, and flew it.

Perfection is not only difficult to achieve, but difficult to maintain. The imperfection in Apollo 13 constituted a near disaster, averted only by outstanding performance on the part of the crew and the ground control team which supported them.⁴⁰

Apollo 14 Launch Operations

The Apollo 14 launch, originally scheduled for February 1970, was postponed to July, then to October, then to December, and finally, after the Apollo 13 review board, was set for 13 January 1971. As Stuart A. Roosa remarked to a press conference, his “was the only crew that’s been six months from launch four times.”⁴¹ The delays allowed the launch team to check and recheck the Apollo hardware, and ensured ample training time for all concerned. Roosa, for example, logged more than 1,000 hours in the command module simulator.

The Apollo 14 command-service module had arrived at KSC on 19 November 1969 and moved into the altitude chamber the following week. the ascent stage of the lunar module was flown down from Bethpage, Long Island, on the 21st; the descent stage followed three days later. When tests in early December revealed a faulty oxidizer flow control valve on the descent stage, a new engine was substituted before Christmas. Operations continued during the holiday season; on the 29th and 30th, North American technicians replaced a defective hydrogen tank in the service module. The first major exercise of the new year involved a successful command-service-lunar module docking test on 9 January 1970. Two days later the S-IC stage sailed into its slip. The Boeing team erected the booster the following day on a mobile launcher. A week later the S-II and S-IVB stages arrived and were placed in low bay stalls. At the operations and checkout building, the descent stage entered the altitude chamber on 16 January. The Grumman team moved the ascent stage to the chamber on the 19th and began a three-day mating operation.

There were no significant problems for the next ten weeks until an accident in mid-April caused about a month’s delay. North American’s work schedule for the 15th included installation of a new inertial measurement unit with an improved gyroscope. A technician accidentally punched a hole in the unit and a pint of water glycol spilled out over the command module’s lower equipment bay. Spacecraft officials initially estimated the cleanup and modification would take nine days. As the North American crew removed wires and equipment, the damage proved more extensive. However, there was no need to rush; the Apollo 13 accident had, by this time, delayed the launch of 14 indefinitely. When the cleanup was completed, a special altitude chamber run was conducted on 15 May to dry out the command module.⁴²

The instrument unit arrived at KSC on 6 May; the following month North American engineers finished modifying the S-II stage’s center engine. During the Apollo 13 flight the pogo effect had reappeared, this time on the second stage. Severe oscillations had forced an early shutdown (two minutes ahead of schedule) of the inboard engine. Although the outboard engines had burned longer and compensated for the loss, NASA officials did not want any more pogo. Marshall and North American engineers devised three changes to the second stage. They installed a helium gas accumulator in the LOX line of the center engine. This reservoir served to dampen fluid pressure oscillations, keeping them out of phase with the vibrations of the thrust structure and engines. North American added a cutoff device to shut down the center engine in case the accumulator failed to control the oscillations. Finally, simplified propellant valves were installed on all five J-2 engines. The valves controlled the propellant mixture to the engines, providing a rich mixture for high thrust during the early portion of the burn and a leaner mixture later.⁴³

In the operations and checkout building, the primary and alternate crews conducted altitude chamber runs in the lunar module and simulated the command-service module altitude run. Grumman engineers traced noise problems in the VHF communications system to the VHF transceiver and the signal processor assembly. After replacing the defective parts, the lunar module team scheduled another run for 10 July.

The date for the altitude test slipped several times. Excessive leakage in a propellant quantity gauge caused the first delay. Tests at Houston and Bethpage resolved the problem by late July, and the rerun was set for 13 August. A conflict with the flight crew training schedule led to a second postponement, this time until the 18th. On 11 August, Houston asked KSC to check the ascent stage’s ball valves, and on the 17th the Office of Manned Space Flight ordered ball valve leak checks on both stages. The test involved the removal of the lunar module from the altitude chamber to the high bay work stands and separation of the two stages. The spherical valves, located above the ascent and descent engines, controlled the flow of hypergolic fuel and oxidizer into the thrust chamber. The launch team used gaseous helium to test the valve seals. The leak checks and other propulsion system tests were completed by the end of August. On 2 September the lunar module returned to the altitude chamber, where all systems were reverified with an altitude run on 18 September.⁴⁴

A stretch-out in the Apollo 14 launch schedule had prompted the decision to revalidate the ball valves. In early July, NASA Headquarters released a new flight schedule moving the launch date from 3 December 1970 to 31 January 1971. The postponement was caused by the Apollo 13 review board’s recommended modifications for the command-service module. The board added a third cryogenic oxygen tank (placed in a previously empty bay of the service module), an auxiliary battery as a backup to the fuel cell, and an emergency supply of drinking water. The modifications recommended for the oxygen tanks - for example, replacing the Teflon insulation on internal wires with stainless steel conduits - required more time.

Following manned altitude runs in early September, North American removed the command-service module from the chamber on the 17th for cryogenic modifications (to comply with the Apollo 13 review board recommendations). The lunar module remained in the chamber until 13 October, when Grumman began installing the landing gear at the high bay stand. In late October, the launch vehicle team detected a condition that might inhibit S-II separation from the booster; paint on a mating flange had bonded it to the second stage. After the upper stages were removed and the area cleaned, the Saturn was restacked on 2 November. The spacecraft was added on the 4th and rollout followed five days later. Milestones passed in routine fashion the last two months:

• 7 DecemberLaunch readiness review
• 14 DecemberSpace vehicle overall test 1 completed
• 17 DecemberFlight readiness review
• 19 DecemberFlight readiness test completed^*
• 19 JanuaryCountdown demonstration test completed
• 25 JanuaryLaunch countdown begun.⁴⁵

One major change in operations during the last month concerned the flight crew’s health program. In December strict rules were instituted to preclude a recurrence of Apollo 13’s measles. At KSC more than one hundred individuals were designated “primary contacts,” i.e., people who had direct contact with the astronauts during the performance of essential duties. The primary contacts underwent immunization against nine diseases and were required to report any illnesses in their families. No one else was permitted in the astronauts’ presence. Beginning at T-21 days, the Medical Surveillance Manager maintained a 24-hour command post near the astronauts’ quarters on the third floor of the operations and checkout building. The astronauts were restricted during the last three weeks to their quarters, the flight crew training building, the flight line, and pad A’s white room. Within these areas, bells and horns warned secondary contacts of approaching astronauts. Certain facilities were also modified. Air filtration units, installed in the air conditioning systems of the operations and checkout building and the flight crew training building, screened out 97% of airborne bacteria. Airtight doors and positive air pressure in the two buildings provided additional protection. Inside the training building an airtight glass partition protected the crew from secondary contacts. Communication with the crew was by intercom. Despite the elaborate precautions, the cooperation of the KSC work force was essential to the success of the program. Posters, adorned with comic strip characters, reminded workers to report any sign of illness. During the first week, five primary contacts reported in sick - all with a respiratory illness. But there was no recurrence of the problems that had beset Apollo 9 and 13.⁴⁶

The Apollo 14 mission attracted widespread interest, in part because of its predecessor’s near disaster, but also because its popular commander, Alan Shepard, was making a comeback after ten years. Following his 15-minute Mercury flight in May 1961, Shepard had been grounded for a minor ear disorder. He had continued in the program, serving for a while as chief of the Astronaut Office at Houston. Flights had passed him by, however, until surgery corrected his ear problem in 1969. Navy Captain Shepard’s presence on the team bothered some junior members of the Flight Crew Operations Branch. They feared that Shepard would “pull rank” and prove uncooperative. But as Riley McCafferty recalled:

Shepard eased himself in and, over a period of about four weeks, he had a relationship with the young engineer on the floor that was good. They had a lot of confidence in each other and they talked back and forth; and the instructor, the young engineer, felt like he could tell Al Shepard, “you fouled up, buddy.”⁴⁷

There were no mishaps during the last week of Apollo 14 operations. The countdown, begun on 25 January, included 102 hours of scheduled tasks and five holds totaling 48 hours. The amount of intended hold time, representing rest periods and contingency planning for unforeseen problems, had changed little in four years. The holds proved largely unnecessary for Apollo 14. On launch day, 31 January, overcast skies gave Walter Kapryan some anxious moments. Light rain was falling on the large Sunday afternoon crowd when Kapryan halted the count at 3:15 p.m., only eight minutes from launch. Within 40 minutes, the cloud peaks had moved from the flight path. Launch officials changed the flight azimuth of the space vehicle from 72 degrees to 75.6 degrees and sent Apollo 14 on its way.⁴⁸

Pruning the Apollo Program

While 1969-71 were the harvest years - four missions that put men on the moon, and the safe return of Apollo 13 after its breakdown in space - they were not so kind to Kennedy Space Center and the men who worked there. Congress cut the NASA budget, NASA cancelled Apollo missions, KSC and its contractors laid off thousands of employees - not in one fell swoop but in a succession of smaller blows. Space enthusiasts had hoped to go on to a manned landing on Mars in the mid-1980s; it was not to be. American public opinion was shifting its priorities to other matters: civil disorders, Vietnam, decaying cities, campus unrest, and inflation. And Apollo was a victim of its own success. For laymen, one moon landing after another was a little boring. Noting the public’s limited interest in Apollo 12, the New York Times concluded that a collective sense of anticlimax was “perhaps predictable considering the intense national emotion spent on the first moon landing four months ago.”⁴⁹

Probably the biggest reason for Apollo’s decline was the detente in American-Soviet relations. In 1961, amid cold war animosities, the United States was trailing the Soviet Union in the world’s most widely publicized form of competition, manned spaceflight. Eight years later, the United States had clearly demonstrated its superiority. Despite the Russian invasion of Czechoslovakia, relations between the two nations had improved. Americans seemed less eager to spend “whatever it took” to surpass the Russians in space. Agreement on a U.S.-U.S.S.R. rendezvous mission (the Apollo-Soyuz flight of 1975), signed before the end of the Apollo program, clearly indicated a new policy of cooperation in space.

NASA budgets marked the contour intervals of Apollo’s descent. Appropriations had exceeded $5 billion in the mid-1960s; in fiscal years 1969 and 1970 they fell below $4 billion. Apollo research and development funding declined from $2.9 billion in FY 1967 to $2 billion in FY 1969. Initially, NASA’s follow-on programs to Apollo-Skylab, an earth orbital laboratory; Voyager, an unmanned Mars mission; and Nerva, a nuclear rocket engine - bore the brunt of the cutbacks. Funding for space programs to follow Apollo appeared in the Johnson administration’s 1968 budget. Congress sharply reduced Nerva and Apollo Applications (Skylab) appropriations, cutting the latter from $454.7 million to $253 million. Voyager was eliminated entirely, while Apollo funds fell by less than 2%. For FY 1969 the Johnson administration budgeted $439.6 million for Apollo Applications, $38 million for 1971 and 1973 unmanned missions to Mars, and $41 million for Nerva. Again all three programs were cut sharply: Skylab eventually received $150 million that year. Apollo received all but $14 million of its $2.039 billion request. After the first lunar landing, however, Apollo lost its immunity to cutbacks, and further tight budgets brought reductions there as well.⁵⁰

The Apollo flight schedule that was published on the eve of the first lunar landing called for nine additional flights before June 1971-a launch every 11 weeks. Apollo 12-15 would develop man’s capability to work in the lunar environment; 16-20 would extend the astronauts’ stay time on the moon to three days and increase their range of exploration. A primary purpose of the latter missions was to study the technological requirements for a potential lunar base.⁵¹

American lunar scientists opposed the rapid pace of the launches. They wanted 6-12 months between flights to study moon samples and plan future experiments. Dr. Lee A. DuBridge, Presidential Science Advisor, expressed the scientists’ viewpoint in congressional testimony on the FY 1970 NASA budget: “Nothing can do more harm to support for the space program than to have a series of missions for which there are no clear objectives - such as a series of manned revisits to the moon without providing the capability to perform new scientific experiments and to exploit interesting new lunar features.”⁵² Three weeks after the first lunar landing, John Noble Wilford, space correspondent for the New York Times, publicized the dispute over Apollo’s future. The scientific community, according to Wilford, sought a larger role in mission planning and more scientist astronauts, as well as more time between missions.⁵³

The July 1969 schedule had included an alternate plan that extended the nine remaining launches by 18 months and provided a launch interval of 4-5 months. Following the success of Apollo 11, NASA officials approved the compromise schedule. In defending the choice, George Mueller acknowledged the scientific arguments but cited other major factors. Among these, Mueller included “operational considerations in keeping a steady workload through the Cape” thereby “minimizing the cost.”⁵⁴

While NASA debated the pace of the remaining Apollo missions, a Space Task Group examined the future of America’s space program. What lay beyond Apollo was the subject of their September 1969 report, “America’s Next Decades in Space.” The report’s sponsors, a panel including Vice President Spiro T. Agnew and NASA Administrator Thomas O. Paine, recommended a balanced manned and unmanned space capability. The group listed three possible NASA programs leading to a manned landing on Mars before the end of the century. The most ambitious plan called for a lunar orbiting station by 1978, a lunar surface base and a 50-man, earthorbiting station in 1980, and the first Mars mission in 1983. The cost of all this would reach an annual $8 billion by 1976. The least ambitious plan postponed the lunar base and earth-orbiting station by three years and left open the date for the initial Mars expedition. The funding estimates for this second plan ran slightly more than $4 billion a year during the 1970s. Apollo missions would lay the groundwork for the lunar surface base. The report generated little support, and NASA’s budget slipped to $3.3 billion the following year.⁵⁵

The decline in Apollo funding was even more severe; a reduction of nearly 50% dropped the program’s budget below the $1 billion mark for the first time in eight years. While much of the decline represented an expected slowdown in costs, the shortage of funds forced drastic program changes. Edward Mathews, KSC’s Apollo Program Manager, notified Debus in March 1970 that FY 1971 funding constraints had eliminated the Apollo 20 mission. There would be an average interval of six months between launches, with Apollo 18-19 put off until 1974 after a year of Skylab missions. Further budget cuts in September included a $50 million reduction for Apollo. NASA officials reluctantly cancelled missions 18 and 19. The flight of Apollo 17 in late 1972 would bring the program to a close.⁵⁶

The Impact of the Apollo Slowdown on KSC

NASA budgets translated into people at KSC. Center employment peaked at 26,000 during Apollo 7 operations in 1968, the same year that KSC’s budget reached a high of $490 million. America’s space program provided over 40% of Brevard County’s employment. By the following spring, KSC faced sharp reductions in both money and manpower. Debus let community leaders know what was coming at a 30 April 1969 briefing. A revised FY 1970 budget, prompted by the Nixon administration’s concern over inflation, lowered KSC’s appropriation from $455 million to $410 million. The entire reduction came out of the $345 million earmarked for Apollo and reflected the intent to slow the program from five to three launches per year. In terms of manpower, the lower budget would reduce KSC’s work force from 23,500 to 18,500 by 30 June 1970. A five-day work week would replace the six- and seven-day weeks that had been typical. Instead of three-shift operations, KSC would employ two, with only enough people on the second to continue necessary tests. Debus took an optimistic view of the cutbacks. The 20% reduction in force affected both stage and support contractors and could probably be met in large part through attrition. Contractor turnover rates at KSC in this period varied from an average of 14% annually for stage contractors to as high as 25% for some support contractors. He thought that “others will see the first lunar landing as a logical milestone in their career plans and move into other programs elsewhere.” It would be “a difficult but orderly retrenchment.”⁵⁷

The reduction took a greater toll than Debus had predicted. By mid-1970 KSC’s work force had fallen to 16,235. The numbers engaged in Apollo launch operations showed an even steeper decline, 50% from the 17,000 high of 1968. KSC civil service employment dropped less sharply in FY 1970, from 2,920 to 2,880. One reason NASA had contracted a large amount of Apollo work had been to avoid an excess of civil service personnel at the end of the program. Subsequently civil service enrollment at KSC was forced down to 2,425 by the end of the program. Newspapers captioned the plight of Brevard County: “Cocoa Beach Boom Reaches Perigee”; “Most of Brevard in Gloomy Mood”; “Depressed Brevard Banks on Space Shuttle.” Reporters described long lines at the employment office and a buyer’s market of empty homes and stores. The articles were exaggerated; unemployment never exceeded 6.5%. Realtors and the Chamber of Commerce launched an aggressive campaign in metropolitan newspapers, describing Brevard homes as the best buys in Florida. Within two years an influx of retirees brought stability to the housing market. In similar fashion small businesses were encouraged to locate in the Cape area. Many members of the Apollo team had found jobs in other parts of the country as stage and support contractors made a strong effort to relocate their personnel.⁵⁸

Although KSC retrenched in orderly fashion, the atmosphere at the center showed a marked change. The pace slowed considerably as the time between launches stretched to eight months. Morale was jeopardized by the space program’s uncertain future. As Alan Shepard, Apollo 14 commander, put it: “We kind of feel like the Wright brothers would have felt if they had been told there’s not enough money for a second plane because there’s no need for airplanes.”⁵⁹ During Apollo’s last three years, the launch team’s esprit was of concern to center and contractor officials alike. The presence of the astronauts remained a positive factor. Launch Director Walter J. Kapryan made them as visible as possible, encouraging their visits with workers at the assembly building and on the pad. Efforts were made to keep everyone busy. That morale never became a significant problem is a tribute to effective civil servant and contractor leadership and to the personal pride of the launch team members.⁶⁰