Success and failure both matter
Experience matters in design. Experience paves the way for the next step… experience in success, and particularly experience in failure.
On January 27, 1967 the astronauts of Apollo 1 were rehearsing pre-flight procedures at Launch Complex 34 atop a Saturn 1B vehicle when a fire started inside the crew cabin. The fire burned rapidly, killing all three astronauts before anyone could open the hatch.
At the time nobody clearly understood what had happened, and a commission was formed led by astronaut Frank Borman to find out every detail possible.
Apollo 1 After Launch Pad Fire
Borman’s team meticulously disassembled the entire capsule looking for the cause. Worse than expected, they found all sorts of problems. Design and assembly were clearly rushed and poorly considered. Workmanship was abysmal including hand tools left inside bulkheads. Most of this hadn’t contributed directly to the fire, yet many were ticking time bombs all the same.
Borman’s specific conclusion—the fire started with faulty wiring, spread rapidly, and quickly killed the astronauts with noxious fumes more directly than the fire itself. Borman’s more generalized conclusion—safety and reliability were taking a back seat to scheduling pressures.
Instead of a regular atmosphere (roughly three parts inert nitrogen to one part oxygen) all American space capsules utilized pure oxygen throughout the entire flight – including pre-flight rehearsals. In space the cabin pressure would be reduced so astronauts breathed about the same amount of oxygen per breath as on earth. Yet sitting on the launch pad the pure oxygen environment would remain at sea-level pressure, and at this concentration NASA was unaware of how easily the smallest smoldering ember could flash into an immediate inferno. After learning this the hard way, since Apollo 1 all American crew cabins have used a sea-level mixture of oxygen and nitrogen prior to launch, and only pure oxygen at lower pressures once on orbit.
In addition to cabin atmosphere, Borman’s team recommended thousands of safety and reliability upgrades. These improvements did not end all future accidents or reduce the risk down to something like airline travel (we have far too little flight experience for that). Yet in the long history of human spaceflight these recommendations instigated the single biggest leap forward in astronaut safety to date — clearly demonstrated just three years later during the flight of Apollo 13 when a tank exploded on approach to the moon, and remaining systems were called upon to serve as a lifeboat in ways hardly imagined at lift-off.
To conserve electricity for the journey home ground controllers ordered a near-complete power-down of primary and backup systems. No manned spacecraft had ever been switched off during a mission nor restarted with frozen condensation coating every wire and electrical unit. Surely a connection would short-circuit with melt-water flowing everywhere. Yet on final approach, when the time came to reenter the Earth’s atmosphere traveling at more than 25,000 MPH flying in a configuration only barely imagined three days earlier, the Command Module – the updated crew cabin section – returned to life and continued to function well beyond it’s operational limits.
Apollo 13 Astronauts Await Recovery Team
Likely for as long as stories are told the survival of this crew will remain one of the great human epics of teamwork, courage, determination and undaunted tenacity in the face of mind-boggling pressures. Yet their survival was rooted not only in the immediate ingenuity during the emergency itself, but more fundamentally in the terrible Apollo 1 launch pad fire three years earlier. Within space engineering circles to this day it is widely understood that without sober experience exhaustively applied from every aspect of the Apollo 1 tragedy, the crew of Apollo 13 would not have made it home alive.
Failure can be an extraordinarily painful teacher – ladling out one problem and disaster after another – yet at these times designers should never ignore the opportunity to learn every lesson they can.
Ken Ramsley
