Earlier in the week....Shane Miller asked for some more Apollo history. Why not start from the beginning? Apollo 1 (initially designated Apollo Saturn-204 and AS-204) was the first manned mission of the U.S. Apollo manned lunar landing program. The planned low Earth orbital test of the Apollo Command/Service Module never made its target launch date of February 21, 1967, because a cabin fire during a launch rehearsal test on January 27 at Cape Canaveral Air Force Station Launch Complex 34 killed all three crew members—Command Pilot Virgil I. Gus Grissom, Senior Pilot Edward H. White II and Pilot Roger B. Chaffee—and destroyed the Command Module (CM). The name Apollo 1, chosen by the crew, was officially retired by NASA in commemoration of them on April 24, 1967. Immediately after the fire, NASA convened the Apollo 204 Accident Review Board to determine the cause of the fire, and both houses of the United States Congress launched their own committee inquiries to oversee NASAs investigation. During the investigation, a NASA internal document citing problems with prime Apollo contractor North American Aviation was publicly revealed by a Senator and became known as the Phillips Report, embarrassing NASA Administrator James E. Webb, who was unaware of the documents existence, and attracting controversy to the Apollo program. Despite congressional displeasure at NASAs openness, both congressional committees ruled that the issues raised in the report had no bearing on the accident, and allowed NASA to continue with the program. Although the ignition source could not be conclusively identified, the astronauts deaths were attributed to a wide range of lethal design and construction flaws in the early Apollo Command Module. Manned Apollo flights were suspended for 20 months while these problems were corrected. The Saturn IB launch vehicle, SA-204, scheduled for use on this mission, was later used for the first unmanned Lunar Module (LM) test flight, Apollo 5. The first successful manned Apollo mission was flown by Apollo 1s backup crew on Apollo 7 in October 1968. Crew Position Astronaut Command Pilot Virgil I. Gus Grissom Senior Pilot Edward H. White II Pilot Roger B. Chaffee Grissom, Chaffee and White participate in Apollo 1 water egress training, June 1966 First backup crew (April – December 1966) Position Astronaut Command Pilot James A. McDivitt Senior Pilot David R. Scott Pilot Russell L. Rusty Schweickart This crew flew on Apollo 9. Second backup crew (December 1966 – January 1967) Position Astronaut Command Pilot Walter M. Wally Schirra Senior Pilot Donn F. Eisele Pilot R. Walter Cunningham This crew flew on Apollo 7. Mission background AS-204 was to be the first manned test flight of the Apollo Command/Service Module (CSM) to Earth orbit, launched on a Saturn IB rocket. AS-204 was to test launch operations, ground tracking and control facilities and the performance of the Apollo-Saturn launch assembly and would have lasted up to two weeks, depending on how the spacecraft performed. Grissom, White, and Chaffee pose in front of their Apollo 1 space vehicle on the launch pad on January 17, 1967, ten days before the fatal fire The CSM for this flight, number 012 built by North American Aviation (NAA), was a Block I version designed before the lunar orbit rendezvous landing strategy was chosen; therefore it lacked capability of docking with the Lunar Module. This was incorporated into the Block II CSM design, along with lessons learned in Block I. Block II would be test-flown with the LM when the latter was ready, and would be used on the Moon landing flights. NASA announced on March 21, 1966, that Grissom, White and Chaffee had been selected to fly the first manned mission. James McDivitt, David Scott and Russell Schweickart were named as the backup crew, and Walter Schirra, Donn Eisele and Walter Cunningham were named as the prime crew for a second Block I CSM flight, AS-205. NASA planned to follow this with an unmanned test flight of the LM (AS-206), then the third manned mission would be a dual flight designated AS-278, in which AS-207 would launch the first manned Block II CSM, which would then rendezvous and dock with the LM launched unmanned on AS-208. At the time, NASA was studying the possibility of flying the first Apollo mission as a joint space rendezvous with the final Project Gemini mission, Gemini 12 in November 1966. But by May, delays in making Apollo ready for flight just by itself, and the extra time needed to incorporate compatibility with the Gemini, made that impractical.This became moot when slippage in readiness of the AS-204 spacecraft caused the last-quarter 1966 target date to be missed, and the mission was rescheduled for February 21, 1967. Grissom was resolved to keep his craft in orbit for a full 14 days if there was any way to do so. A newspaper article published on August 4, 1966, referred to the flight as Apollo 1. CM-012 arrived at the Kennedy Space Center on August 26, labeled Apollo One by NAA on its packaging. In October 1966, NASA announced the flight would carry a small television camera to broadcast live from the Command Module. The camera would also be used to allow flight controllers to monitor the spacecrafts instrument panel in flight. Television cameras were carried aboard all manned Apollo missions. By December 1966, the second Block I flight AS-205 was canceled as unnecessary; and Schirra, Eisele and Cunningham were reassigned as the backup crew for Apollo 1. McDivitts crew was now promoted to prime crew of the Block II / LM mission, re-designated AS-258 because the AS-205 launch vehicle would be used in place of AS-207. A third manned mission was planned to launch the CSM and LM together on a Saturn V (AS-503) to an elliptical medium Earth orbit (MEO), to be crewed by Frank Borman, Michael Collins and William Anders. McDivitt, Scott and Schweickart had started their training for AS-278 in CM-101 when the Apollo 1 accident occurred. Mission insignia Grissoms crew received approval in June 1966 to design a mission patch with the name Apollo 1. The designs center depicts a Command/Service Module flying over the southeastern United States with Florida (the launch point) prominent. The Moon is seen in the distance, symbolic of the eventual program goal. A yellow border carries the mission and astronaut names with another border set with stars and stripes, trimmed in gold. The insignia was designed by the crew, with the artwork done by North American Aviation employee Allen Stevens. Spacecraft problems The Apollo Command/Service Module spacecraft was much bigger and far more complex than any previously implemented spacecraft design. In October 1963, Joseph F. Shea was named Apollo Spacecraft Program Office (ASPO) manager, responsible for managing the design and construction of both the CSM and the LM. When North American shipped spacecraft CM-012 to Kennedy Space Center on August 26, 1966, there were 113 significant incomplete planned engineering changes, and an additional 623 engineering change orders were made after delivery. Grissom was so frustrated with the inability of the training simulator engineers to keep up with the actual spacecraft changes, that he took a lemon from a tree by his house and hung it on the simulator. In a spacecraft review meeting held with Shea on August 19, 1966 (a week before delivery), the crew expressed concern about the amount of flammable material (mainly nylon netting and Velcro) in the cabin, which the technicians found convenient for holding tools and equipment in place. Though Shea gave the spacecraft a passing grade, after the meeting they gave him a crew portrait they had posed with heads bowed and hands clasped in prayer, with the inscription: It isnt that we dont trust you, Joe, but this time weve decided to go over your head. Shea gave his staff orders to tell North American to remove the flammables from the cabin, but did not supervise the issue personally. You sort of have to put that out of your mind. Theres always a possibility that you can have a catastrophic failure, of course; this can happen on any flight; it can happen on the last one as well as the first one. So, you just plan as best you can to take care of all these eventualities, and you get a well-trained crew and you go fly. — Gus Grissom, in a December 1966 interview Accident Plugs-out test The launch simulation on January 27, 1967, was a plugs-out test to determine whether the spacecraft would operate nominally on (simulated) internal power while detached from all cables and umbilicals. Passing this test was essential to making the February 21 launch date. The test was considered non-hazardous because neither the launch vehicle nor the spacecraft was loaded with fuel or cryogenics, and all pyrotechnic systems were disabled. At 1:00 pm EST (1800 GMT) on January 27, first Grissom, then Chaffee, and White entered the Command Module fully pressure-suited, and were strapped into their seats and hooked up to the spacecrafts oxygen and communication systems. There was an immediate problem: Grissom noticed a strange odor in the air circulating through his suit which he compared to sour buttermilk, and the simulated countdown was held at 1:20 pm, while air samples were taken. No cause of the odor could be found, and the countdown was resumed at 2:42 pm. (The accident investigation found this odor not to be related in any way to the fire.) Three minutes after the count was resumed, the hatch installation was started. The hatch consisted of three parts: a removable inner hatch, which stayed inside the cabin; a hinged outer hatch, which was part of the spacecrafts heat shield; and an outer hatch cover, which was part of the boost protective cover enveloping the entire Command Module to protect it from aerodynamic heating during launch and from launch escape rocket exhaust in the event of a launch abort. The boost hatch cover was partially but not fully latched in place, because the flexible boost protective cover was slightly distorted by some cabling run under it to provide the simulated internal power. (The spacecrafts fuel cell reactants were not loaded for this test.) After the hatches were sealed, the air in the cabin was replaced with pure oxygen at 16.7 psi (1.15 bar), 2 psi higher than atmospheric pressure. Further problems included episodes of high oxygen spacesuit flow, which tripped an alarm. The likely cause was determined to be the astronauts movements, which were detected by the spacecrafts inertial guidance gyroscope and Grissoms stuck-open microphone. The open microphone was part of the third major problem, with the communications loop connecting the crew, the Operations and Checkout Building and the Complex 34 blockhouse control room. The problems led Grissom to remark: How are we going to get to the Moon if we cant talk between three buildings? The simulated countdown was held again at 5:40 pm while attempts were made to fix the problem. All countdown functions up to the simulated internal power transfer had been successfully completed by 6:20 pm, but at 6:30 the count remained on hold at T minus 10 minutes. Fire The crew members were using the time to run through their checklist again, when a voltage transient was recorded at 6:30:54 (23:30:54 GMT). Ten seconds later (at 6:31:04), Chaffee exclaimed Hey!, and scuffling sounds followed for two seconds. White then reported, Ive got a fire in the cockpit!. Some witnesses said that they saw White on the television monitors, reaching for the inner hatch release handle as flames in the cabin spread from left to right and licked the window. The final voice transmission is believed to have come from Chaffee. Six seconds after Whites report of a fire in the cockpit, a voice cried out, Theres a bad fire!. The sound of the spacecrafts hull rupturing was heard immediately afterwards, followed by Im burning up! and a scream. The transmission then ended abruptly at 6:31:21, only 17 seconds after the first report of fire. The cabin had ruptured due to rapidly expanding gases from the fire, which over-pressurized the Command Module to 29 psi (2.0 bar). Flames and gases then rushed outside the Command Module through open access panels to two levels of the pad service structure. Intense heat, dense smoke, and ineffective gas masks designed for toxic fumes rather than heavy smoke hampered the ground crews attempts to rescue the men. There were fears the Command Module had exploded, or soon would, and that the fire might ignite the solid fuel rockets in the launch escape tower above the Command Module, which would have likely killed nearby ground personnel. It took five minutes to open all three hatch layers, and they could not drop the inner hatch to the cabin floor as intended, so they pushed it out of the way to one side. The initial phase of the fire lasted only about 15 seconds before the Command Modules hull ruptured. As the cabin depressurized, the convective rush of air caused the flames to spread rapidly, beginning the second phase. The third phase began when most of the atmosphere was consumed. At this point, the fire largely stopped, but massive amounts of smoke, dust, carbon monoxide, and fumes now filled the cabin. Although the cabin lights remained lit, the ground crew was at first unable to find the astronauts through the dense smoke. As the smoke cleared they found the bodies but were not able to remove them. The fire had partly melted Grissoms and Whites nylon space suits and the hoses connecting them to the life support system. Grissom had removed his restraints and was lying on the floor of the spacecraft. Whites restraints were burned through, and he was found lying sideways just below the hatch. It was determined that he had tried to open the hatch per the emergency procedure, but was not able to do so against the internal pressure. Chaffee was found strapped into his right-hand seat, as procedure called for him to maintain communication until White opened the hatch. Because of the large strands of melted nylon fusing the astronauts to the cabin interior, removing the bodies took nearly 90 minutes. Investigation As a result of the in-flight failure of the Gemini 8 mission on March 17, 1966, NASA Deputy Administrator Robert Seamans wrote and implemented Management Instruction 8621.1 on April 14, 1966, defining Mission Failure Investigation Policy And Procedures. This modified NASAs existing accident procedures, based on military aircraft accident investigation, by giving the Deputy Administrator the option of performing independent investigations of major failures, beyond those for which the various Program Office officials were normally responsible. It declared, It is NASA policy to investigate and document the causes of all major mission failures which occur in the conduct of its space and aeronautical activities and to take appropriate corrective actions as a result of the findings and recommendations. Immediately after the Apollo 1 fire, Seamans directed establishment of the Apollo 204 Review Board chaired by Langley Research Center director Floyd L. Thompson, which included astronaut Frank Borman, spacecraft designer Maxime Faget, and six others. To avoid the possible appearance of a conflict of interest, NASA Administrator James E. Webb got the approval of President Lyndon B. Johnson for an internal NASA investigation, and notified appropriate leaders of Congress. According to Webbs official NASA bio: ...Webb went to President Lyndon Johnson and asked that NASA be allowed to handle the accident investigation and direct the recovery from the accident. He promised to be truthful in assessing blame and pledged to assign it to himself and NASA management as appropriate. Seamans immediately ordered all Apollo 1 hardware and software impounded, to be released only under control of the Board. On February 3, two members, a Cornell University professor and North Americans Chief engineer for Apollo, left the Board, and a U.S. Bureau of Mines professor joined. After thorough stereo photographic documentation of the CM-012 interior, the board ordered its disassembly using procedures tested by disassembling the identical CM-014, and conducted a thorough investigation of every part. The board also reviewed the astronauts autopsy results and interviewed witnesses. Seamans sent Webb weekly status reports of the investigations progress, and the Board issued its final report on April 5, 1967. According to the Board, Grissom suffered severe third degree burns on over one-third of his body and his spacesuit was mostly destroyed. White suffered third degree burns on almost half of his body and a quarter of his spacesuit had melted away. Chaffee suffered third degree burns over almost a quarter of his body and a small portion of his spacesuit was damaged. The autopsy report confirmed that the primary cause of death for all three astronauts was cardiac arrest caused by high concentrations of carbon monoxide. Burns suffered by the crew were not believed to be major factors, and it was concluded that most of them had occurred postmortem. Asphyxiation happened after the fire melted the astronauts suits and oxygen tubes, exposing them to the lethal atmosphere of the cabin. The review board identified five major factors which combined to cause the fire and the astronauts deaths. Ignition source The review board determined that the electrical power momentarily failed at 23:30:55 GMT, and found evidence of several electric arcs in the interior equipment. However, they were unable to conclusively identify a single ignition source. They determined that the fire most likely started near the floor in the lower left section of the cabin, close to the Environmental Control Unit. It spread from the left wall of the cabin to the right, with the floor being affected only briefly. The engulfed area on the left contained the manual depressurization valve which would have been used to vent the cabin atmosphere to the outside. Consequently, the astronauts were unable to reach it, however this was in any case insufficient to prevent heat and pressure buildup. They noted a silver-plated copper wire running through an environmental control unit near the center couch had become stripped of its Teflon insulation and abraded by repeated opening and closing of a small access door. This weak point in the wiring also ran near a junction in an ethylene glycol/water cooling line which had been prone to leaks. The electrolysis of ethylene glycol solution with the silver anode was a notable hazard which could cause a violent exothermic reaction, igniting the ethylene glycol mixture in the CMs corrosive test atmosphere of pure, high-pressure oxygen. In 1968, a team of MIT physicists went to Cape Kennedy and performed a static discharge test in the CM-103 Command Module while it was being prepared for the launch of Apollo 8. With an electroscope, they measured the approximate energy of static discharges caused by a test crew dressed in nylon flight pressure suits and reclining on the nylon flight seats. The MIT investigators repeatedly found sufficient energy for ignition was discharged when crew-members shifted in their seats and then touched the spacecrafts aluminum panels. Flammable materials in the cabin The review board cited many types and classes of combustible material close to ignition sources. The NASA crew systems department had installed 34 square feet (3.2 m2) of Velcro throughout the spacecraft, almost like carpeting. This Velcro was found to be flammable in a high-pressure 100% oxygen environment. Up to 70 pounds of other non-metallic flammable materials had also crept into the design. Buzz Aldrin states in his book Men From Earth that the flammable material had been removed (per the crews August 19 complaints and Joseph Sheas order), but was replaced prior to the August 26 delivery to Cape Kennedy. Pure oxygen atmosphere The plugs-out test had been run to simulate the launch procedure, with the cabin pressurized with pure oxygen at the nominal pre-launch level of 16.7 psi (1.15 bar), 2 psi above standard sea level atmospheric pressure. This is more than five times the 3 psi partial pressure of oxygen in the atmosphere, and provides an environment in which materials not normally considered highly flammable will burst into flame. The high-pressure oxygen atmosphere was consistent with that used in the Mercury and Gemini programs. The pressure before launch was deliberately greater than ambient in order to drive out the nitrogen-containing air and replace it with pure oxygen. After liftoff, the pressure would have been reduced to the in-flight level of 5 psi (0.34 bar), providing sufficient oxygen for the astronauts to breathe while reducing the fire risk. The Apollo 1 crew had tested this procedure with their spacecraft in the Operations and Checkout Building altitude (vacuum) chamber on October 18 and 19, 1966, and the backup crew of Schirra, Eisele and Cunningham had repeated it on December 30. When designing the Mercury spacecraft, NASA had considered using a nitrogen/oxygen mixture to reduce the fire risk near launch, but rejected it based on two considerations. First, nitrogen used with the in-flight pressure reduction carried the clear risk of decompression sickness (known as the bends). But the decision to eliminate the use of any gas but oxygen was crystalized when a serious accident occurred on April 21, 1960, in which McDonnell Aircraft test pilot G.B. North passed out and was seriously injured when testing a Mercury cabin / spacesuit atmosphere system in a vacuum chamber. The problem was found to be nitrogen-rich (oxygen-poor) air leaking from the cabin into his spacesuit feed. North American Aviation had suggested using an oxygen/nitrogen mixture for Apollo, but NASA overruled this. The pure oxygen design also carried the benefit of saving weight, by eliminating the need for nitrogen tanks. In his monograph Project Apollo: The Tough Decisions, Deputy Administrator Seamans wrote that NASAs single worst mistake in engineering judgment was not to run a fire test on the Command Module prior to the plugs-out test. In the first episode of the 2009 BBC documentary series NASA: Triumph and Tragedy, Jim McDivitt said that NASA had no idea how a 100% oxygen atmosphere would influence burning. Similar remarks by other astronauts were expressed in the 2007 documentary film In the Shadow of the Moon. Other oxygen fires Several fires in high-oxygen environments had been known to occur prior to the Apollo fire. For example, in 1962, USAF Colonel B. Dean Smith was conducting a test of the Gemini space suit with a colleague in a pure oxygen chamber at Brooks Air Force Base in San Antonio, Texas when a fire broke out, destroying the chamber. Smith and his partner narrowly escaped. Other oxygen fire occurrences are documented in certain U.S. reports archived in the National Air and Space Museum, such as: Selection of Space Cabin Atmospheres. Part II: Fire and Blast Hazaards [sic] in Space Cabins. (Emanuel M. Roth; Dept of Aeronautics Medicine and Bioastronautics, Lovelace Foundation for Medical Education and Research. c.1964–1966.) Fire Prevention in Manned Spacecraft and Test Chamber Oxygen Atmospheres. (MSC. NASA General Working Paper 10 063. October 10, 1966) On January 28, 1986, the Soviet Union disclosed that cosmonaut Valentin Bondarenko died after a fire in a high-oxygen isolation chamber on March 23, 1961, less than three weeks before the first Vostok manned space flight. This revelation caused some speculation whether the Apollo 1 disaster might have been averted had NASA been aware of the incident. Hatch design The higher than atmospheric cabin pressure made it impossible for the senior pilot to remove the inner hatch, until the excess cabin pressure (16.7 psi absolute, 2 psi above ambient) had been vented. Emergency procedure called for the command pilot to open the cabin vent first, but this was located near the origin of the fire, and while the system could easily vent the normal pressure, it was utterly incapable of handling the extra increase in pressure (to at least 29 psi absolute) caused by the fire. North American had originally suggested the hatch open outward and use explosive bolts to blow the hatch in case of emergency, as had been done in Project Mercury. NASA did not agree, arguing the hatch could accidentally open, as it had on Grissoms Liberty Bell 7 flight, so the inward-opening hatch was selected early in the Block I design. Before the fire, the Apollo astronauts had recommended changing the design to an outward-opening hatch, and this was already slated for inclusion in the Block II Command Module design. According to Donald K. Slaytons testimony before the House investigation of the accident, this was based on ease of exit for spacewalks and at the end of flight, rather than for emergency exit. Emergency preparedness The board noted that: the test planners had failed to identify the test as hazardous; the emergency equipment (such as gas masks) were inadequate to handle this type of fire; that fire, rescue, and medical teams were not in attendance; and that the spacecraft work and access areas contained many hindrances to emergency response such as steps, sliding doors, and sharp turns. Political fallout Committees in both houses of the United States Congress with oversight of the space program soon launched investigations, including the Senate Committee on Aeronautical and Space Sciences, chaired by Senator Clinton P. Anderson. Seamans, Webb, Manned Space Flight Administrator Dr. George E. Mueller, and Apollo Program Director Maj Gen Samuel C. Phillips were called to testify before Sen. Andersons committee. In the February 27 hearing, Senator Walter F. Mondale asked Webb if he knew of a report of extraordinary problems with the performance of North American Aviation on the Apollo contract. Webb replied he did not, and deferred to his subordinates on the witness panel. Mueller and Phillips responded they too were unaware of any such report. However, in late 1965, just over a year before the accident, Phillips had headed a tiger team investigating the causes of inadequate quality, schedule delays, and cost overruns in both the Apollo CSM and the Saturn V second stage (for which North American was also prime contractor.) He gave an oral presentation (with transparencies) of his teams findings to Mueller and Seamans, and also presented them in a memo to North American president John L. Atwood, to which Mueller appended his own strongly worded memo to Atwood. During Mondales 1967 questioning about what was to become known as the Phillips Report, Seamans was afraid Mondale might actually have seen a hard copy of Phillips presentation, and responded that contractors have occasionally been subjected to on-site progress reviews; perhaps this was what Mondales information referred to. Mondale continued to refer to the Report despite Phillips refusal to characterize it as such, and angered by what he perceived as Webbs deception and concealment of important program problems from Congress, he questioned NASAs selection of North American as prime contractor. Seamans later wrote that Webb roundly chastised him in the cab ride leaving the hearing, for volunteering information which led to the disclosure of Phillips memo. On May 11, Webb issued a statement defending NASAs November 1961 selection of North American as the prime contractor for Apollo. This was followed on June 9 by Seamans filing a seven-page memorandum documenting the selection process. Webb eventually provided a controlled copy of Phillips memo to Congress. The Senate committee noted in its final report NASAs testimony that the findings of the [Phillips] task force had no effect on the accident, did not lead to the accident, and were not related to the accident, but stated in its recommendations: Notwithstanding that in NASAs judgment the contractor later made significant progress in overcoming the problems, the committee believes it should have been informed of the situation. The committee does not object to the position of the Administrator of NASA, that all details of Government/contractor relationships should not be put in the public domain. However, that position in no way can be used as an argument for not bringing this or other serious situations to the attention of the committee. Freshman Senators Edward W. Brooke III and Charles H. Percy jointly wrote an Additional Views section appended to the committee report, chastising NASA more strongly than Anderson for not having disclosed the Phillips review to Congress. Mondale wrote his own, even more strongly worded Additional View, accusing NASA of evasiveness, ... lack of candor, ... patronizing attitude toward Congress, ... refusal to respond fully and forthrightly to legitimate Congressional inquiries, and ... solicitous concern for corporate sensitivities at a time of national tragedy. The potential political threat to Apollo blew over, due in large part to the support of President Lyndon B. Johnson, who at the time still wielded a measure of influence with the Congress from his own Senatorial experience. He was a staunch supporter of NASA since its inception, had even recommended the Moon program to President John F. Kennedy in 1961, and was skilled at portraying it as part of Kennedys legacy. Internal acrimony developed between NASA and North American over assignment of blame. North American argued unsuccessfully it was not responsible for the fatal error in spacecraft atmosphere design. Finally, Webb contacted Atwood, and demanded either he or Chief Engineer Harrison A. Storms resign. Atwood elected to fire Storms. On the NASA side, Joseph Shea became unfit for duty in the aftermath and was removed from his position, although not fired. r/max
Posted on: Sat, 22 Nov 2014 22:00:00 +0000
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