CAPE CANAVERAL — Bright winter flowers bloom amid the weeds around an unsettling concrete and steel hulk that marks one of the darkest days in American space history – the Apollo 1 command module was destroyed by fire during a launch rehearsal test on Jan 27, 1967, marking one of America’s darkest moments in space exploration history.
A fire quickly consumed Velcro pads and nylon nets stored inside a cabin pressurized with pure oxygen, prompting emergency services personnel to evacuate it immediately.
What caused the fire?
Apollo 1’s launch pad fire was an inconvenient reminder of the risks involved in human space exploration, yet its lessons led to advancements in astronaut safety. NASA used these lessons learned from Apollo 1 to create stringent safety protocols which are now the standard across all space missions.
Fire was caused by multiple factors, including flammable materials and inadequate fire safety measures. The spacecraft cabin was pressurized with pure oxygen at levels higher than atmospheric pressure, while extensive amounts of highly combustible material existed within its walls – creating an explosive environment where a fire could quickly spread across it and ultimately bring down its structure.
Start a fire requires three key ingredients: heat, fuel (something that burns) and oxygen. In the case of Apollo 1, heat was provided by electrical arcs under several wires within its left-hand couch causing sparks from these arcs that ignited pure-oxygen atmosphere and spread rapidly as fire.
Once the fire spread, it generated intense heat and released high concentrations of toxic gases including carbon monoxide – eventually shattering the CM pressure vessel and killing all five astronauts within minutes due to asphyxiation.
Tragic circumstances were compounded by astronauts being unable to escape from their spacecraft due to its inward-opening hatch, making escape even more impossible when fire broke out inside cabin. Furthermore, opening procedure was lengthy and time consuming – further compounding tragedy. The astronauts were trapped inside for five minutes before becoming overcome by smoke and heat; ultimately succumbing to asphyxiation and their eventual deaths. Spacecraft technicians attempted to reach astronauts through outer hatches, but could not gain entry due to dense smoke and heat. Furthermore, opening an outer hatch could set off Apollo’s launch escape system which could ignite its service structure and eventually explode it altogether.
Why did the fire occur?
On January 27, 1967, America’s Moon landing program suffered a tragic blow when three astronauts aboard Apollo 1 perished in a fire during a test on its launch pad. The fire broke out during a “plugs-out” ground test and quickly spread throughout its command module and command module crew members Virgil I. “Gus” Grissom, Edward H. White and Roger B. Chaffee all died due to smoke inhalation within minutes; blame was assigned for both technical and management lapses; both chambers of Congress conducted their own committee investigations into these tragic events.
Fire began due to an electrical short circuit in some wiring under Grissom’s footrest, quickly spreading due to combustible nylon material and pure oxygen cabin atmosphere. Within seconds of ignition, it had enveloped both astronauts and their capsule; rescue was impossible since its pressure prevented opening the hatch against internal pressure of cabin; additionally, this event destroyed communication systems within their spacecraft, leaving astronauts unable to signal for assistance from nearby technicians.
Investigations following the fire revealed that its ignition likely resulted from electrical arcing between several wires under Grissom’s footrest which were not adequately protected or grounded, covered with Teflon coating but not sufficiently fire-proof to safeguard delicate wiring from extreme temperatures inside the capsule cabin. Furthermore, since this test involved unfueling of rocket, normal safety precautions were waived as this was regarded as less hazardous test procedure.
Technicians attempted to open the hatch, but it required an intricate process requiring multiple bolts be released with a ratchet ratchet and under intense fire and smoke conditions, they barely had time to loosen even one bolt before being overwhelmed by flames and smoke.
This fire was an eye-opener to the importance of careful planning and preparation in space program operations, leading to substantial changes to astronaut safety protocols and spacecraft design. Furthermore, all future space missions will prioritize crew safety over schedule objectives.
What were the consequences of the fire?
Astronauts perished in an instantaneous nine-second fire whose flames burned for only nine seconds but caused fatal exposure to poisonous carbon monoxide fumes that asphyxiated them to death. Furthermore, this tragedy damaged their capsule so severely that it was never able to reenter Earth’s atmosphere after returning from space – leaving no way out for their crew as their cabin had already been sealed shut by flames and thick smoke before reaching it.
At that time, only Joe Shea knew of such combustible materials being present in the command module. Shea had raised concerns during a meeting with North American engineers and demanded they clean out the capsule, however his orders weren’t implemented until one month before launch.
Shea believed the issue could be resolved by replacing Velcro and nylon nets with something more durable, something which wouldn’t deteriorate under pure oxygen, and possibly using a coating which wouldn’t ignite even at pressures higher than normal sea level; but his suggestion did not gain approval.
Hours before their accident, Grissom and White had performed a “plugs-in” test in their CM. Unfortunately, their backup crew of Wally Schirra, Don Eisele and Walt Cunningham had to evacuate as soon as the fire broke out; they hated Block 1. As he left Block 1, Grissom asked Shea if he’d like to join them for an “unplugging” test so he could witness how messy everything really was. Shea agreed and they all joined them back in their cockpit for another test before going back out again before an incident happened that day.
The fire started from an electrical spark in a bundle of wires that ran beneath and to the left of Grissom’s couch, and quickly spread through nylon materials and Velcro strips attached to cabin walls. Once ignited, however, its reach quickly expanded exponentially.
Technicians raced to open the hatch, but only had minutes before fire and smoke consumed them as well. Each hinge was secured in place with multiple bolts and required special ratchets in order to open; operating these mechanisms while combatting flames and smoke proved nearly impossible; so technicians had no option but to wait.
What were the lessons learned from the fire?
This fire was not only tragic; it also provided us with valuable lessons about space travel and safety. It taught us to remain alert regarding risks related to space exploration; ultimately it underscored how critical it is that each mission be developed with safety as its top priority.
After the fire, NASA conducted extensive reviews of their procedures and equipment. Their priority was preventing future fires in spacecraft environments; to this end they developed new fire-resistant materials which they tested extensively; additionally they created emergency escape mechanisms which could be deployed if required.
Apollo 1 fire was an unfortunate and preventable tragedy caused by multiple factors. A spark from faulty wiring ignited an initial blaze, which spread quickly due to pure oxygen cabin atmosphere and presence of combustible nylon materials. Furthermore, escape was impossible because plug door hatch wasn’t designed to open against cabin pressure; ultimately accelerating fire spread through lack of fire extinguishers aboard spacecraft.
An important lesson we took away from the Apollo 1 fire was that when conducting root cause analysis, it is critical to take all aspects of a situation into account – not only its immediate cause (fire on launch pad at Cape Kennedy), but also where and what task was being performed at that moment (simulated countdown test).
Apollo 1 fire teaches us another valuable lesson: that even small mistakes can have dire repercussions. For example, this fire might have been prevented had crew not removed netting placed under their couches during ground testing that was meant to catch any hardware that might fall during testing, yet ended up becoming the source of its own flames instead. Had it not been removed it is likely that fire would have spread throughout their couches and perhaps to astronauts themselves.