Apollo 1 (initially designated Apollo Saturn-204 and AS-204) was scheduled to be the first manned test flight mission of the U.S. Apollo manned lunar landing program and the Apollo Command/Service Module (CSM) launched on a Saturn IB rocket.
The CSM block I number 012 was built by North American Aviation.
On March 21, 1966, NASA announced that Astronauts Gus Grissom, Edward White and Roger Chaffee had been selected to fly the first manned Apollo test mission.
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 of 1966, delays in making Apollo ready for flight just by itself, and the extra time needed to incorporate compatibility with the Gemini, made that impractical and the mission was rescheduled for February 21, 1967.
A newspaper article published on August 4, 1966, referred to the flight as “Apollo 1” for the first time and the name stuck.
CSM-012 arrived at the Kennedy Space Center on August 26, 1966 labeled Apollo One on its packaging.
In October of 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 spacecraft’s instrument panel in flight.
The Apollo Command/Service Module spacecraft was far more complex than any previously implemented spacecraft design.
Gus Grissom became 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 Apollo CSM simulator.
Then during a spacecraft review meeting held on August 19, 1966, 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 NASA 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 isn’t that we don’t trust you, Joe, but this time we’ve decided to go over your head.
NASA then ordered North American to remove the flammables from the cabin, but failed to supervise the issue.
“You sort of have to put that out of your mind. There’s 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
Plugs-out launch simulation test January 27, 1967
The launch simulation on January 27, 1967 at Cape Canaveral Air Force Station Launch Complex 34 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 on January 27th, first Grissom, then Chaffee, and finally White entered the Command Module fully pressure-suited, and were strapped into their seats and hooked up to the spacecraft’s 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 later 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 spacecraft’s 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 spacecraft’s 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.
Then an episode of high oxygen spacesuit flow tripped an alarm.
The likely cause was determined to be the astronauts’ movements, which were detected by the spacecraft’s inertial guidance gyroscope and Grissom’s stuck-open microphone.
The open microphone became a major problem with the communications loop connecting the crew, the Operations and Checkout Building and the Complex 34 blockhouse control room.
This problem led Gus Grissom to remark:
“How are we going to get to the Moon if we can’t 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.
The crew members were using the time to run through their checklist again, when a voltage transient was recorded at 6:30:54 pm.
Ten seconds later (at 6:31:04), Roger Chaffee exclaimed “Hey!”, and scuffling sounds followed for two seconds.
Edward White then reported, “I’ve 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.
Then six seconds after White’s report of a “fire in the cockpit”, a voice believed to have come from Roger Chaffee cried out, “There’s a bad fire!”.
The sound of the spacecraft’s hull rupturing was heard immediately afterwards, followed by “I’m burning up!” and a scream.
NASA declined to speculate on which Astronaut made the final voice transmission out of respect to the families.
Then all transmissions 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 crew’s 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 Module’s 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 Grissom’s and White’s 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. White’s 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 them took nearly 90 minutes.
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 NASA’s 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 document’s existence, and attracting controversy to the Apollo program.
Despite congressional displeasure at NASA’s 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 Apollo manned lunar landing 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 name Apollo 1, was officially retired by NASA in commemoration of them on April 24, 1967.
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 1’s backup crew on Apollo 7 in October of 1968.
Now WE know em